AN645

Silicon Laboratories

Si477X PROGRAMMING GUIDE

Manufacturer: Silicon Laboratories

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command. The device will, in turn, provide a response depending on the type of command that was sent. responses from the device using 2-wire mode (I2C compatible). Table 1. Si477x Programming Guide and Firmware Revisions

Rev. 0.3 3 Two-wire bus mode uses the SCL and SDA pins for signa ling. A transaction begins with the START condition, which occurs when SDA falls while SCL is high. Next, the system controller drives an 8-bit control word serially on SDA, which is captured by the device on rising edges of SCL. The control word consists of a seven-bit device address followed by a read/write bit (read = 1, write = 0) . The device acknowledges the control word by driving SDA low on the next falling edge of SCL. For write operations, the system controller next sends a da ta byte on SDA, which is captured by the device on rising edges of SCL. The device acknowledges each data byte by driving SDA low for one cycle on the next falling edge of SCL. For each write transaction, the first byte is a command and the following bytes are arguments. For read operations, after the device has acknowledged the control byte, it will drive an eight-bit data byte on SDA, changing the state of SDA on the falling edges of SCL. The system controller acknowledges each data byte by driving SDA low for one cycle on the next falling edge of SCL. If a data byte is not acknowledged by the system controller, the transaction will end. For each read transaction, the first byte is the status byte and the following bytes are the response data from the receiver. A 2-wire transaction ends with the STOP condition, which occurs when SDA rises while SCL is high.

It is possible to configure the receiver for operation with a crystal or an external clock. Refer to Table 2 below. described in section “5.2. Powerup from a Patch”. Table 2. Clocking Options

Rev. 0.3 5 5.1. Powerup from Internal Memory 1. Supply VA, VD, VIO1 and VIO2 while keeping the RSTB=0. Power supplies may be sequenced in any order. 2. After a minimum of 100 µs, set RSTB=1. 3. After a minimum of 100 µs, continue to the next step. 4. Send the POWER_UP command for the desired functi on (AM, FM). Example (with crystal 36.4 MHz, FM function): 1. Supply VA, VD, VIO1 and VIO2 while keeping the RSTB = 0 START 2. After a minimum of 100uS, set RSTB = 1 3. After a minimum of 100uS, continue to the next step 4. Send the POWER_UP command for the desired function (AM, FM) 5. Commence normal operation 6. Send POWER_DOWN command

The device is ready to commence normal operation and accept additional commands. Refer to Figure 3.

Figure 3. Powerup Timing

If desired, send the POWER_DOWN command.

ARG3 0x07 Disables CTS interrupt, crystal bias=7. ARG4 0x12 FM function, crystal frequency 36.4 MHz. ARG5 0x11 Crystal, receiver 1. ARG3 0x03 Disables CTS interrupt, crystal bias = 3. ARG4 0x12 FM function, crystal frequency 36.4 MHz. ARG5 0x12 External clock, receiver.

Rev. 0.3 7 Example: 7. It is now possible to move to the powerup state by returning to step 4. POWER_DOWN Command Action Data Description CMD 0x11 POWER_DOWN ARG1 0x00 Disable oscillator (ARG1 may be omitted with the same result) STATUS →0x80 CTS=1

8 Rev. 0.3 5.2. Powerup from a Patch 1. Supply VA, VD, VIO1 and VIO2 while keeping the RSTB = 0 START 2. After a minimum of 100uS, set RSTB = 1 3. After a minimum of 100uS, continue to the next step 7. Send the POWER_UP command with boot loader function 8. Send patch data. 5. Send PART_INFO command. 6. Send POWER_DOWN command. 9. Send the POWER_UP command for the desired function (AM, FM) 10. Commence normal operation. 11. Send POWER_DOWN command. A B Verify Firmware and ROM revision? A B 4. Send the POWER_UP command for the desired function (AM, FM)

Rev. 0.3 9 1. Supply VA, VD, VI01 and VI02 while keeping the RSTB=0. Power supplies may be sequenced in any order. 2. After a minimum of 100 µs, set RSTB=1. 3. After a minimum of 100 µs, proceed to the next step. 4. (Optional – step 1 of 3 to verify part firmware revision and ROM revision.) Both part firmware revision and ROM revision must be compatible with a partial patch and ROM revision must be compatible with a full patch. Send the POWER_UP command for the desired function (AM, FM). Example (with crystal

36.4 MHz, FM function):

Example (with external clock 36.4 MHz, FM function): 5. (Optional—step 2 of 3 to verify part firmware revision and ROM revision). Verify part firmware revision and ROM revision. Send the PART_INFO command. POWER_UP Command Action Data Description CMD 0x01 POWER_UP ARG1 0x77 Normal operation. ARG2 0x28 Crystal load capacitance = 11.08 pF. ARG3 0x07 Disables CTS interrupt, crystal bias=7. ARG4 0x12 FM function, crystal frequency 36.4 MHz. ARG5 0x11 Crystal, receiver 1. STATUS →0x80 POWER_UP Command Action Data Description CMD 0x01 POWER_UP ARG1 0x77 Normal operation. ARG2 0x00 Crystal load capacitance = 0 pF. ARG3 0x03 Disables CTS interrupt, crystal bias=3. ARG4 0x12 FM function, clock frequency 36.4 MHz. ARG5 0x12 External clock, receiver 1. STATUS →0x80

(Optional—step 3 of 3 to verify part firmwa re revision and ROM revision.) Send the POWER_DOWN
Send the POWER_UP command for boot loader function.

RESP6 →0x00 Reserved, values will vary. RESP7 →0x00 Reserved, values will vary. RESP9 →0x00 Reserved, values will vary. Table 3. Si477x Firmware and ROM Compatibility

Rev. 0.3 11 Example (with external clock 36.4 MHz, boot loader function): 8. Send the patch data. The patch file provided by Silicon Labs typically has a .csg extension. The system controller must send each line of 8 bytes, wait for a CTS, then send the next line of 8 byte s, etc., until the entire patch has been sent. An example showing the first few lines and final line of a patch file is shown below. Note that the “#” character indicates a comment and the patch file indicates the required ROM ID for a partial or full download. If the checksum fails, the part issues an error code, ERR (bit 6 of the STATUS byte received after each 8-byte transfer), and halts. The part must be reset to recover from this error condition. The following is an example of a patch file: # COPYRIGHT=2011 Silicon Laboratories, Inc. # GENERATED=13:53 May 23 2011 # ROMID=0x04 # PATCHID=0x228C # REQUIRES=NONE # SIZE=8272 # FUNCTION=FMRX # MAJOR=8 # MINOR=0 # BUILD=8 POWER_UP Command Action Data Description CMD 0x01 POWER_UP ARG1 0x77 Normal operation. ARG2 0x28 Crystal load capacitance = 11.08 pF. ARG3 0x07 Disables CTS interrupt, crystal bias=7. ARG4 0x02 Boot loader function, crystal frequency 36.4 MHz. ARG5 0x11 Crystal, receiver 1. STATUS →0x80 POWER_UP Command Action Data Description CMD 0x01 POWER_UP ARG1 0x77 Normal operation. ARG2 0x00 Crystal load capacitance = 0 pF. ARG3 0x03 Disables CTS interrupt, crystal bias=3. ARG4 0x02 Boot loader function, clock frequency 36.4 MHz. ARG5 0x12 External clock, receiver 1. STATUS →0x80

12 Rev. 0.3 # CRCT=0x81CF # CRCM=0x0A6C # CRCP=0xEC8D # CRCX=0x66EE # CRCY=0x6381 # CRCZ=0xA805 0x04,0x11,0x81,0xCF,0x00,0x00,0x0D,0xC6 0x05,0xAE,0xE1,0xBD,0xB4,0x90,0x07,0x33 0x06,0xD9,0x3D,0x11,0xF7,0x25,0xCB,0x06 0x17,0x7A,0xF8,0xD0,0x71,0x10,0x3F,0xB7 0x1F,0xBF,0xFF,0x7E,0x42,0xE7,0x53,0x05 [Additional Lines] 0x08,0x21,0xAB,0xB5,0xF1,0x7A,0xD6,0x5A 0x08,0x10,0x0E,0x9E,0x3B,0xD1,0x01,0xF4 0x08,0xBF,0x8D,0x94,0xB0,0x2D,0xCF,0xFF 0x05,0x8D,0xB1,0x22,0xF2,0x8D,0x22,0x8C # END

Rev. 0.3 13 Example: 9. Send the POWER_UP command for the desired function (AM, FM). Example (with crystal 36.4 MHz, FM function): Example (with external clock 36.4 MHz, FM function): First line of the patch file example Action Data Description CMD 0x04 ARG1 0x11 ARG2 0x81 ARG3 0xCF ARG4 0x00 ARG5 0x00 ARG6 0x0D ARG7 0xC6 STATUS →0x80 Second line of the patch file example CMD 0x05 ARG1 0xAE ARG2 0xE1 ARG3 0xBD ARG4 0xB4 ARG5 0x90 ARG6 0x07 ARG7 0x33 STATUS →0x80 POWER_UP Command Action Data Description CMD 0x01 POWER_UP ARG1 0x77 Normal operation. ARG2 0x28 Crystal load capacitance = 11.08 pF. ARG3 0x07 Disables CTS interrupt, crystal bias=3. ARG4 0x12 FM function, cr ystal frequency 36.4 Hz. ARG5 0x11 Crystal, receiver 1. STATUS →0x80

14 Rev. 0.3 10. The device is ready to commence normal operation and accept additional commands. 11. If desired, send the POWER_DOWN command. Example: 12. It is now possible to move to the powerup state by returning to step 7. POWER_UP Command Action Data Description CMD 0x01 POWER_UP ARG1 0x77 Normal operation. ARG2 0x00 Crystal load capacitance = 0 pF. ARG3 0x03 Disables CTS interrupt, crystal bias=3. ARG4 0x12 FM function, crystal frequency 36.4 MHz. ARG5 0x12 External clock, receiver 1. STATUS →0x80 POWER_DOWN Command Action Data Description CMD 0x11 POWER_DOWN ARG1 0x00 Disable oscillator (ARG1 may be omitted with the same result) STATUS →0x80 CTS=1

Rev. 0.3 15 6. Digital Audio Interface The digital audio interface operates in slave mode and supports 5 different audio data formats: I2S Audio Left-Justified Audio Right-Justified Audio DSP Audio DSP Left-Justified Audio In I2S mode, the MSB is captured on the second rising edge of DCLK following each DFS transition. The remaining bits of the word are sent in order down to the LSB. The Left Channel is transferred fi rst when the DFS is low, and the Right Channel is transferred when the DFS is high. In left-justified mode, the MSB is captured on the firs t rising edge of DCLK following each DFS transition. The remaining bits of the word are sent in order down to the LSB. The Left Channel is transferred first when the DFS is high, and the Right Channel is transferred when the DFS is low. In right-justified format, by default, th e LSB is captured on the last rising edg e of DCLK in each valid DFS interval. The left channel is transferred first when the DFS is high, and the right channel is transferred when the DFS is low. In DSP format, the DFS becomes a pulse with a width of one DCLK period. The left channel is transferred first, followed right away by the right channel. There are two options in transferring the digital audio data in DSP format; the MSB of the left channel can be transferred on the fi rst rising edge of DCLK following the DFS pulse (left- justified DSP format) or on the second rising edge. In all audio formats, depending on the word size, DCLK frequency, and sample rates, there may be unused DCLK cycles after the LSB of each word before the next DFS tr ansition and MSB of the next word. In addition, the user can configure the MSB to be captured on the falling edge of DCLK via properties. The number of audio bits can be configured for 8, 16, 20, or 24 bits.

Figure 4. I2S Audio Format Figure 5. Left-Justified Audio Format Figure 6. Right-Justified Audio Format

1 DCLK 1 DCLK

Figure 7. DSP Audio Format Figure 8. DSP Left-Justified Audio Format

1 DCLK

Digital ZIF I/Q Interface

In I2S format, by default, the MSB is captured on the second rising edge of IQCLK following each IQFS transition. The remaining bits of the word are sent in order, down to the LSB. transition. The remaining bits of the word are sent in order, down to the LSB. IQCLK following the IQFS pulse (left-justified DSP format) or on the second rising edge. of baseband I/Q bits is configured for 16 bits. Table 4. ZIF I/Q Interface Description

Figure 9. I2S ZIF Format Figure 10. Left-Justified ZIF Format Figure 11. Right-Justified ZIF Format

1 IQCLK 1 IQCLK

Figure 12. DSP ZIF Format Figure 13. DSP Left-Justified ZIF Format

1 IQCLK

The device supports a number of industry-standard sampling rates including 650, 675, and 744.1875 kHz. samples rates for interface to an HD radio demodulator/decoder or DSP. Table 5. Crystal/Reference Clock Frequency Requirements for the ZIF I/Q Sample Rates and

Table 6. Command Timing Parameters for Common Commands Table 7. Command Timing Parameters for FM Receiver number of channels to next valid channel.

The timing diagram for fast tune is shown in Figure 15. Figure 15. Fast Tune Timing Diagram Table 8. Command Timing Parameters for AM Receiver number of channels to next valid channel.

The following properties and commands are common to all receiver modes. Table 9. Common Receiver Command Summary function (AM, FM) and audio interface configuration. 0x02 PART_INFO Returns the part information of the device. 0x11 POWER_DOWN Power-down the device. 0x12 FUNC_INFO Returns th e firmware revision and patch revision. 0x13 SET_PROPERTY Sets the value of a property. 0x14 GET_PROPERTY Retrieve a property's value. 0x15 GET_INT_STATUS Read interrupt status bits. 0x17 AGC_STATUS Reports the status of the AGC. 0x18 DIG_AUDIO_PIN_CFG Configures the digital audio pins. 0x1A GPIO_CTL_PIN_CFG Configures GPIO1 and GPIO2 pins. 0x1B ANA_AUDIO_PIN_CFG Configures the analog audio pins. 0x1C INTB_PIN_CFG Configures beha vior of INTB and A1 pins. Table 10. Common Receiver Property Summary 0x3600 Configures digital audio input format. Configures digital audio output format.

Sets the analog audio volume. Table 11. Status Response for the FM Receiver 0 = Wait before sending next command. 1 = Clear to send next command. 5:4 Reserved Values may vary. Received Signal Quality Interrupt. 0 = Received Signal Quality measurement has not been triggered. 1 = Received Signal Quality measurement has been triggered. Radio Data System Interrupt. 0 = Radio data system interrupt has not been triggered. 1 = Radio data system interrupt has been triggered. Automatically Controlled Features Interrupt. 0 = ACF measurement has not been triggered. 1 = ACF measurement has been triggered. Seek/Tune Complete Interrupt. 0 = Tune complete has not been triggered. 1 = Tune complete has been triggered. Table 10. Common Receiver Property Summary (Continued)

Table 12. Status Response for the AM Receiver 0 = Wait before sending next command. 1 = Clear to send next command. 5:4 Reserved Values may vary. 0 = Received Signal Quality measurement has not been triggered. 1 = Received Signal Quality measurement has been triggered. Automatically Controlled Features Interrupt. 0 = ACF measurement has not been triggered. 1 = ACF measurement has been triggered. Seek/Tune Complete Interrupt.

Table 13. Response When ERR Bit is Set

Rev. 0.3 29 9.1.1. Common Receiver Commands Command 0x01 POWER_UP The POWER_UP command initiates the boot process to move the device from powerdown to powerup mode. The boot can occur from internal device memory or a system controller downl oaded patch. This command powers up the device with the specified function (FM Receive, AM Receive). Power-up is complete when the CTS bit is set. This is the only command that may be sent while the device is powered down. Command B i t 76543210 CMD 0x01 ARG1 IBIAS7X XSTART ARG2 00 XCLOAD[5:0] ARG3 CTSIEN INTSEL FAST- BOOT 0 XIBIASHC XIBIAS[2:0] ARG4 FUNC[3:0] FREQ[3:0] ARG5 00010 XMODE[2:0] ARG Bit Name Function 1 7 IBIAS7X Crystal 7x bias current. 0=All other configurations. 1=Receiver 1 in a two/three receiver configuration with 37.209375, 36.4, or 37.8 MHz crystal. 1 6:0 XSTART Oscillator Startup. 0010001=Start up multiple tuner. 1110111=Normal operation. 2 7:6 Reserved Always write 00. 2 5:0 XCLOAD[5] Selects the amount of additional on-chip capacitance to be connected between XTAL1 and gnd and between XTAL2 and gnd. One half of the capacitance value shown here is the additional load capacitance pre- sented to the xtal. The minimum step size is 0.277 pF. The required value will be layout-dependent. Range is 0–0x3F i.e.(0–16.33 pF) The Si477x EVB sets XCLOAD=0x28. 3 7 CTSIEN CTS interrupt enable. 0=Disable. 1=Enable. 3 6 INTSEL CTS interrupt pin select. 0=A1 pin. 1=INTB pin. 3 5 FASTBOOT Speeds boot time when set. It is recommended to set this bit with all crystals. 3 3 XIBIASHC Crystal high current. 0=Single receiver configuration. 1=Multiple receiver configuration.

30 Rev. 0.3 3 2:0 XIBIAS Crystal bias current. 0=37.209375, 36.4, or 37.8 MHz crystal or external clock. 7=37.209375, 36.4, or 37.8 MHz crystal. 4 7:4 FUNC[3:0 Selects the boot function of the device. 0 = Boot Loader. 1=F M R e c e i v e . 2=A M R e c e i v e . Note: Values other than those listed may result in unpredictable behavior. 4 3:0 FREQ[3:0] Selects the crystal frequency. 1 = 37.209375 MHz. 2=3 6 . 4M H z . 3=3 7 . 8M H z . 5 4 Reserved Always write 00010. 5 2:0 XMODE[2:0] Crystal mode. 1=Crystal. 2=External clock. ARG Bit Name Function

Rev. 0.3 31 Command 0x02 PART_INFO The PART_INFO command returns the chip revision, part firmware major, minor, and build revision, and ROM ID. The command is complete when the CTS bit (and opti onal interrupt) is set. The command may only be sent in powerup mode. Command Response B i t 76543210 CMD 0x02 Bit 7 6 5 4 3 2 1 0 STATUS CTS ERR XX RSQINT RDSINT ACFINT STCINT RESP1 CHIPREV[7:0] RESP1 PART[7:0] RESP3 PMAJOR[7:0] RESP4 PMINOR[7:0] RESP5 PBUILD[7:0] RESP6 Reserved RESP7 Reserved RESP8 ROMID[7:0] RESP Bit Name Function 1 7:0 CHIPPREV Chip Revision 2 7:0 PART Part Number, last two digits of part number 3 7:0 PMAJOR Part Major Revision 4 7:0 PMINOR Part Minor Revision 5 7:0 PBUILD Part Build Version 6 7:0 Reserved Values may vary. 7 7:0 Reserved Values may vary. 8 7:0 ROMID ROM ID

32 Rev. 0.3 Command 0x11 POWER_DOWN The POWER_DOWN command moves the device from powerup to powerdown mode. The CTS bit (and optional interrupt) is set when it is safe to send the next co mmand. This command may only be sent when in powerup mode. Note that only the POWER_UP command is accepted in powerdown mode. If the system controller writes a command other than POWER_UP when in powerdown mode, the device will not respond. The device will only respond when a POWER_UP command is written. It is po ssible to power down a device and leave the oscillator running. This may be desirabl e in multiple receiver app lications in which the device driving th e oscillator for other devices is to be placed in powerdown without affecting the other devices. Command Response B i t 76543210 CMD 0x11 ARG1 0X O S C ARG Bit Name Function 1 7:0 Reserved Always write 0. 20 X O S C 0=Full powerdown. 1=Powerdown and leave oscillator running. B i t 76543210 STATUS CTS ERR XX RSQINT RDSINT ACFINT STCINT Note: The above response shows status bits for FM Receive mode (see Table 11). See Table 12 for status bits for AM Receive mode.

Rev. 0.3 33 Command 0x12 FUNC_INFO The FUNC_INFO command returns the firmware revision and patch revision for currently-loaded functional mode firmware (AM, FM). The command is complete when the CTS bit (and optional interrupt) is set. This command may only be sent in powerup mode. Command Response B i t 76543210 CMD 0x12 B i t 76543210 STATUS CTS ERR XX RSQINT RDSINT ACFINT STCINT RESP1 FWMAJOR[7:0] RESP2 FWMINOR1[7:0] RESP3 FWMINOR2[7:0] RESP4 PATCHH[7:0] RESP5 PATCHL[7:0] RESP6 FUNC[7:0] Note: The above response shows status bits for FM Receive mode (see Table 11 on page 26). See Table 12 on page 27 for status bits for AM Receive mode. RESP Bit Name Function 1 7:0 FWMAJOR[7:0] Firmware Major Revision. 2 7:0 FWMINOR1[7:0] Firmware Minor1 Revision. 3 7:0 FWMINOR2[7:0] Firmware Minor2 Revision. 4 7:0 PATCHH[7:0] Patch ID High Byte (HEX). 5 7:0 PATCHL[7:0] Patch ID Low Byte (HEX). 6 7:0 FUNC[7:0] Returns the current functional mode:

1 FM Receive

2 AM Receive

34 Rev. 0.3 Command 0x13 SET_PROPERTY The SET_PROPERTY command sets the value of a property. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This command may only be sent in powerup mode. Command Response B i t 76543210 CMD 0x13 ARG1 00000000 ARG2 PROPH[7:0] ARG3 PROPL[7:0] ARG4 PROPDH[7:0] ARG5 PROPDL[7:0] ARG Bit Name Function 1 7:0 Reserved Always write to 0. 27 : 0 PROPH [7:0] Property Address High Byte This byte, in combination with PROPL, is used to specify the property to modify. 37 : 0 PROPL [7:0] Property Address Low Byte This byte, in combination with PROPH, is used to specify the property to modify. 47 : 4 PROPDH [7:0] Property Value High Byte This byte, in combination with PROPDL, is used to set the property value. 57 : 0 PROPDL [7:0] Property Value Low Byte This byte, in combination with PROPDH, is used to set the property value. B i t 76543210 STATUS CTS ERR XX RSQINT RDSINT ACFINT STCINT Note: The above response shows status bits for FM Receive mode (see Table 11 on page 26). See Table 12 on page 27 for status bits for AM Receive mode.

Rev. 0.3 35 Command 0x14 GET_PROPERTY The GET_PROPERTY command retrieves a property's value. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This command may only be sent in powerup mode Command Response B i t 76543210 CMD 0x14 ARG1 00000000 ARG2 PROPH[7:0] ARG3 PROPL[7:0] ARG Bit Name Function 1 7:0 Reserved Always write 0. 27 : 0 P R O P H[7:0] Property Address High Byte. This byte, in combination with PROPL, is used to specify the property to get. 37 : 0 P R O P L[7:0] Property Address Low Byte. This byte, in combination with PROPH, is used to specify the property to get. B i t 76543210 STATUS CTS ERR XX RSQINT RDSINT ACFINT STCINT RESP1 XXXXXXXX RESP2 PROPDH[7:0] RESP3 PROPDL[7:0] Note: The above response shows status bits for FM Receive mode (see Table 11 on page 26). See Table 12 on page 27 for status bits for AM Receive mode. RESP Bit Name Function 1 7:0 Reserved Response values may vary. 27 : 0 P R O P D H[7:0] Property Value High Byte. This byte, in combination with PROPD L, represents the requested property value. 37 : 0 P R O P D L[7:0] Property Value Low Byte. This byte, in comb ination with PROPD H, represents the requested property value.

36 Rev. 0.3 Command 0x15 GET_INT_STATUS The GET_INT_STATUS command updates the bits of the st atus byte. This command should be called after any command that sets the STCINT, ACFINT, RDSINT, ASQINT, or RSQINT bits. When polling, this command should be periodically called to monitor the STATUS byte, and, when using interrupts, this command should be called after the interrupt is set to update the STATUS byte. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This command may only be set in powerup mode. Command Response Command 0x17 AGC_STATUS The AGC_STATUS command reports the current status of the AGC for FM mode. The command is complete when the CTS bit (and optional interrupt) is set. This command may only be sent when in powerup mode. B i t 76543210 CMD 0x15 B i t 76543210 STATUS CTS ERR XX RSQINT RDSINT ACFINT STCINT Note: The above response shows status bits for FM Receive mode (see Table 11 on page 26). See Table 12 on page 27 for status bits for AM Receive mode. B i t 76543210 CMD 0x17 R E S P 76543210 STATUS CTS ERR XX RSQINT RDSINT ACFINT STCINT RESP1 XX MIXHI MXLO LNAHI LNALO X X RESP2 FMAGC1 RESP3 FMAGC2 RESP4 PGAGAIN RESP5 FMLNAG Note: The above response shows status bits for FM Receive mode (see Table 11 on page 26). See Table 12 on page 27 for status bits for AM Receive mode.

Rev. 0.3 37 RESP Bit Name Function 1 7:6 Reserved Values may vary. 15 M X H I 0 = FM Mixer PD high threshold is not tripped. 1 = FM Mixer PD high threshold is tripped. 14 M X L O 0 = FM Mixer PD low threshold is not tripped. 1 = FM Mixer PD low threshold is tripped. 13 L N A H I 0 = FM LNA PD high threshold is not tripped. 1 = FM LNA PD high threshold is tripped. 12 L N A L O 0 = FM LNA PD low threshold is not tripped. 1 = FM LNA PD low threshold is tripped. 1 1:0 Reserved Values may vary. 27 : 0 F M A G C 1 The parallel combination of these resistors indicates the current FMAGC1 attenuator resistance. The total resistance value at the pin is 800/FMAGC1. 0=1 0k —no attenuation 1 = 800  2 = 400  4 = 200  8 = 100  16 = 50  32 = 25  64 = 12.5  128 = 6.25  37 : 0 F M A G C 2 The parallel combination of these resistors indicates the current FMAGC2 attenuator resistance. The total resistance value at the pin is 800/FMAGC2. 0 = 10 k —no attenuation 1 = 800  2 = 400  4 = 200  8 = 100  16 = 50  32 = 25  64 = 12.5  128 = 6.25  4 7:0 PGAGAIN PGA gain in dB Range: 8–33 57 : 0 F M L N A G FM LNA Gain in dB Range: 2–14

38 Rev. 0.3 Command 0x18 DIG_AUDIO_PIN_CFG The DIG_AUDIO_PIN_CFG command configures the digita l audio pins. Ensure that DCLK and DFS are stable before this command is sent. Writing an argument byte to a non-zero value will change the state of a pin. Writing an argument byte to 0 will not change the state of the pin and is useful when using this command to query the state of the pins. The command is complete when the CTS bit (and optional interrupt) is set. This command may only be sent in powerup mode. Command B i t 76543210 CMD 0x18 ARG1 0 DCLK[6:0] ARG2 0 DFS[6:0] ARG3 0D O U T [ 6 : 0 ] ARG4 0 BLEND[6:0] ARG Bit Name Function 1 7 Reserved Always write 0. 1 6:0 DCLK[6:0] 0 = Do not modify the behavior of this pin. 1 = Disable both the output and input drivers so the pin is completely inactive. 1 M pull down is enabled. 10 = Configure this pin as part of the digital audio interface in slave mode. 2 7 Reserved Always write 0. 2 6:0 DFS[6:0] 0 = Do not modify the behavior of this pin. 1 = Disable both the output and input drivers so the pin is completely inactive. 1 M pull down is enabled. 10 = Configure this pin as part of the digital audio interface in slave mode. 3 7 Reserved Always write 0. 3 6:0 DOUT[6:0] 0 = Do not modify the behavior of this pin. 1 = Disable both the output and input drivers so the pin is completely inactive. 1 M pull down is enabled. 12 = Configure this pin as digital out on I2S port 1. 13 = Configure this pin as digital in on I2S port 1. (Si4777 only) 4 7 Reserved Always write 0. 4 6:0 BLEND[6:0] 0 = Do not modify the behavior of this pin. 1 = Disable both the output and input drivers so the pin is completely inactive. 1 M pull down is enabled. 13 = Configure this pin as digital in on I2S port 1. (Si4777 only) 23 = Configure this pin as the input that selects the mode of the I2S audio combiner (analog or HD) (Si4777 only).

Rev. 0.3 39 Response B i t 76543210 STATUS CTS ERR XX RSQINT RDSINT ACFINT STCINT RESP1 Reserved DCLK[6:0] RESP2 Reserved DFS[6:0] RESP3 Reserved DOUT[6:0] RESP4 Reserved BLEND[6:0] Note: The above response shows status bits for FM Receive mode (see Table 11 on page 26). See Table 12 on page 27 for status bits for AM Receive mode. RESP Bit Name Function 1 7 Reserved Values may vary. 1 6:0 DCLK[6:0] 1 = Disabled. 10 = Configured as part of the digital audio interface in slave mode. 2 7 Reserved Values may vary. 2 6:0 DFS[6:0] 1 = Disabled. 10 = Configured as part of the digital audio interface in slave mode. 3 7 Reserved Values may vary. 3 6:0 DOUT[6:0] 1 = Disabled. 12 = Configured as digital out on I2S port 1. 13 = Configured as digital in on I2S port 1. (Si4777 only) 4 7 Reserved Values may vary. 4 6:0 BLEND[6:0] 1 = Disabled. 13 = Configured as digital in on I2S port 1. 23 = Configured as the input that selects the mode of the I2S audio combiner (analog or HD). (Si4777 only)

40 Rev. 0.3 Command 0x19 ZIF_PIN_CFG (Si4777 Only) The ZIF_PIN_CFG command configures the digital I/Q pins. Writing an argument byte to a non-zero value will change the state of a pin. Writing an argument byte to 0 will not change th e state of the pin and is useful when using this command to query the state of the pins.The command is complete when the CTS bit (and optional interrupt) is set. This command may only be sent in powerup mode. Command B i t 76543210 CMD 0x19 ARG1 0 IQCLK[6:0] ARG2 0 IQFS[6:0] ARG3 0I O U T [ 6 : 0 ] ARG4 0 QOUT[6:0] ARG Bit Name Function 1 7 Reserved Always write 0. 1 6:0 IQCLK[6:0] 0 = Do not modify the behavior of this pin. 1 = Disable both the output and input drivers so the pin is com- pletely inactive. 1 M pull down is enabled. 21 = Configure this pin as part of the I/Q interface in master mode. 2 7 Reserved Always write 0. 2 6:0 IQFS[6:0] 0 = Do not modify the behavior of this pin. 1 = Disable both the output and input drivers so the pin is com- pletely inactive. 1 M pull down is enabled. 21 = Configure this pin as part of the I/Q interface in master mode. 3 7 Reserved Always write 0. 3 6:0 IOUT[6:0] 0 = Do not modify the behavior of this pin. 1 = Disable both the output and input drivers so the pin is com- pletely inactive. 1 M pull down is enabled. 22 = Configure this pin as I out. 4 7 Reserved Always write 0. 4 6:0 QOUT[6:0] 0 = Do not modify the behavior of this pin. 1 = Disable both the output and input drivers so the pin is com- pletely inactive. 1 M pull down is enabled. 22 = Configure this pin as Q out.

Rev. 0.3 41 Response B i t 76543210 STATUS CTS ERR XX RSQINT RDSINT ACFINT STCINT RESP1 Reserved IQCLK[6:0] RESP2 Reserved IQFS[6:0] RESP3 Reserved IOUT[6:0] RESP4 Reserved QOUT[6:0] Note: The above response shows status bits for FM Receive mode (see Table 11 on page 26). See Table 12 on page 27 for status bits for AM Receive mode. RESP Bit Name Function 1 7 Reserved Values may vary. 1 6:0 IQCLK[6:0] 1 = Disabled. 21 = Configured as part of the I/Q interface in master mode. 2 7 Reserved Values may vary. 2 6:0 IQFS[6:0] 1 = Disabled. 21 = Configured as part of the I/Q interface in master mode. 3 7 Reserved Values may vary. 3 6:0 IOUT[6:0] 1 = Disabled. 22 = Configured I out. 4 7 Reserved Values may vary. 4 6:0 QOUT[6:0] 1 = Disabled. 22 = Configured Q out.

42 Rev. 0.3 Command 0x1A GPIO_CTL_PIN_CFG Configures the state (high or low) of GPO1 and GPO2 pins. The command is complete when the CTS bit (and optional interrupt) is set. This command may only be sent in powerup mode. Command B i t 76543210 CMD 0x1A ARG1 Reserved ICIN [6:0] ARG2 Reserved ICIP [6:0] ARG3 Reserved ICON[6:0] ARG4 Reserved ICOP[6:0] ARG Bit Name Function 1 7 Reserved Always write 0. 1 6:0 ICIN [6:0] 0 = Do not modify the behavior of this pin. 1 = Disable both the output and input drivers so the pin is com- pletely inactive. 1 M pull down in enabled. 2 = Configure this pin as an output (GPO1) and drive it low. 3 = Configure this pin as an output (GPO1) and drive it high. 2 7 Reserved Always write 0. 2 6:0 ICIP [6:0] 0 = Do not modify the behavior of this pin. 1 = Disable both the output and input drivers so the pin is com- pletely inactive. 1 M pull down in enabled. 2 = Configure this pin as an output (GPO2) and drive it low. 3 = Configure this pin as an output (GPO2) and drive it high. 3 7 Reserved Always write 0. 3 6:0 ICON[6:0] 0 = Do not modify the behavior of this pin. 1 = Disable both the output and input drivers so the pin is com- pletely inactive. 1 M pull down in enabled. 10 = Configure this pin as part of the digital audio interface in slave mode (DCLK). (Si4777 only). 4 7 Reserved Always write 0. 4 6:0 ICOP[6:0] 0 = Do not modify the behavior of this pin. 1 = Disable both the output and input drivers so the pin is com- pletely inactive. 1 M pull down in enabled. 14 = Configure this pin as part of the digital audio interface in slave mode (DOUT). (Si4777 only).

Rev. 0.3 43 Response B i t 7 6 5 4 3210 STATUS CTS ERR XX RSQINT RDSINT ACFINT STCINT RESP1 Reserved ICIN[6:0] RESP2 Reserved ICIP[6:0] RESP3 Reserved ICON[6:0] RESP4 Reserved ICOP[6:0] Note: The above response shows status bits for FM Receive mode (see Table 11 on page 26). See Table 12 on page 27 for status bits for AM Receive mode. RESP Bit Name Function 1 7 Reserved Values may vary. 1 6:0 ICIN[6:0] 1 = Disabled. 2 = GPO1 output, Driving low. 3 = GPO1 output, Driving high. 2 7 Reserved Values may vary. 2 6:0 ICIP[6:0] 1 = Disabled. 2 = GPO2 output, Driving low. 3 = GPO2 output, Driving high. 3 7 Reserved Values may vary. 3 6:0 ICON[6:0] 1 = Disabled. 10 = Configured as part of the digital audio interface in slave mode on I2S port 2. (DCLK). (Si4777 only) 4 7 Reserved Values may vary. 4 6:0 ICOP[6:0] 1 = Disabled. 14 = Configured as digital out on I2S port 2 (DOUT). (Si47777 only).

44 Rev. 0.3 Command 0x1B ANA_AUDIO_PIN_CFG The ANA_AUDIO_PIN_CFG command configures the analog aud io pins. Writing an argument byte to 0 will not change the state of the pin and is useful when using this command to query the state of the pins. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This command may only be sent in powerup mode. Command Response B i t 76543210 CMD 0x1B ARG1 0 LROUT[6:0] ARG Bit Name Function 1 7 Reserved Always write 0. 1 6:0 LROUT[6:0] 0 = Do not modify the behavior of this pin. 1 = Disable the output drivers, so the pins are completely inac- tive and can be left floating. 2 = Configure the LOUT/ROUT pins to output audio. 3 = Configure LOUT for MPX and disable ROUT. 4 = Configure LOUT/ROUT for HD Split mode: ROUT = Ana- log out; LOUT = HD out. Bit 7 6 5 4 3 2 1 0 STATUS CTS ERR XX RSQINT RDSINT ACFINT STCINT RESP1 X LROUT[6:0] Note: The above response shows status bits for FM Receive mode (see Table 11 on page 26). See Table 12 on page 27 for status bits for AM Receive mode. RESP Bit Name Function 1 7 Reserved Values may vary. 1 6:0 LROUT[6:0] 1 = The output drivers are disabled, so the pins are com- pletely inactive and can be left floating. 2 = LOUT/ROUT pins configured to output audio. 3 = LOUT is configured for MPX out and ROUT is dis- abled.

Rev. 0.3 45 Command 0x1C INTB_PIN_CFG The INTB_PIN_CFG comma nd configures INTB and A1 pins. Writing an argument byte to 0 will not change the state of the pin and is useful when using this command to query the state of the pins. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This command may only be sent in powerup mode. Command Response B i t 7 6 5 432 1 0 CMD 0x1C ARG1 Reserved INTB[6:0] ARG2 Reserved A1[6:0] ARG Bit Name Function 1 7 Reserved Always write to 0. 1 6:0 INTB[6:0] 0 = Do not modify the behavior of this pin. 1 = Disable both the output and input drivers so the pin is completely inactive and can be left floating. 10 = Configure this pin as part of the digital audio inter- face in slave mode. 40 = Configure this pin as the interrupt. 2 7 Reserved Always write to 0. 26 : 0A 1 [ 6 : 0 ] 0 = Do not modify the behavior of this pin. 1 = Disable both the output and input drivers so the pin is completely inactive and can be left floating. 40 = Configure this pin as the interrupt. B i t 76543210 Status CTS ERR XX RSQINT RDSINT ACFINT STCINT RESP1 Reserved INTB[6:0] RESP 2 Reserved A1[6:0] Note: The above response shows status bits for FM Receive mode (see Table 11 on page 26). See Table 12 on page 27 for status bits for AM Receive mode.

46 Rev. 0.3 RESP Bit Name Function 1 7 Reserved Values may vary. 1 6:0 INTB[6:0] 1 = Disabled. 10 = Configured as part of the digital audio interface in slave mode. 40 = Configured as the interrupt. 2 7 Reserved Values may vary. 26 : 0A 1 [ 6 : 0 ] 1 = Disabled. 40 = Configured as the interrupt.

Rev. 0.3 47 9.1.2. Common Receiver Properties Property 0x0000 INT_CTL_ENABLE The INT_CTL_ENABLE property enables top-level interrupt so urces. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0x0000 INT_CTL_ENABLE 15:13 12 11 10 9 8 7 6 5 4 3 2 1 0

000 ASQREP RSQREP RDSREP ACFREP STCREP CTSIE N ERRIEN 0 ASQIEN RSQIEN RDSIEN ACFIEN STCIEN

000 0 0 0 0 0 0 0 0 0 0 0 0 0 Bit Name Function 15:13 Reserved Always write 0.

12 ASQREP Repeat interrupt pulse when ASQINT is set, even if a previous interrupt was

generated but not acknowledged.

11 RSQREP Repeat interrupt pulse when RSQINT is set, even if a previous interrupt was

generated but not acknowledged.

10 RDSREP Repeat interrupt pulse when RDSINT is set, even if a previous interrupt was

generated but not acknowledged.

9 ACFREP Repeat interrupt pulse when ACFINT is set, even if a previous interrupt was

generated but not acknowledged.

8 STCREP Repeat interrupt pulse when STCIEN is set, even if a previous interrupt was

generated but not acknowledged. 7 CTSIEN Interrupt when CTS is set. 6 ERRIEN Interrupt when ERR is set. 5 Reserved Always write 0. 4 ASQIEN Interrupt when ASQINT is set. 3 RSQIEN Interrupt when RSQIEN is set. 2 RDSIEN Interrupt when RDSINT is set. 1 ACFIEN Interrupt when ACFINT is set. 0 STCIEN Interrupt when STCIEN is set.

48 Rev. 0.3 Property 0x0200 DIGITAL_IO_INPUT_SAMPLE_RATE (Si4777 only) The DIGITAL_IO_INPUT_SAMPLE_RATE property sets the digital input sample rate in units of Hz. Set the sample rate to 0 to disable digital audio. The CTS bit (and opti onal interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 48000 Units: Hz DIGITAL_IO_INPUT_SAMPLE_RATE 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 INPUT_SAMPLE_RATE[15:0] 0xBB80 Bit Name Function 15:0 INPUT_SAMPLE_RATE[15:0] Sets the digital input sample rate in units of Hz. Default is 48000. Range is 32000–48000.

Rev. 0.3 49 Property 0x0201 DIGITAL_IO_INPUT_FORMAT (Si4777 only) The DIGITAL_IO_INPUT_FORMAT property configures di gital audio input format. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be sent. This property may only be set or read in powerup mode. Default: 0x3600 DIGITAL_IO_INPUT_FORMAT 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 0x0 SLOT_SIZE[2:0] SAMPL_SIZE[2:0] BI TORDER SWAP CLKINV FRAMING_MODE[3:0] 0 Bit Name Function 15:14 Reserved Always write 0. 13:11 SLOT_SIZE[2:0] Defines the width of the data channel. This is only used in right justified modes. 2 = 8 bits. 4=1 6 b i t s . 5=2 0 b i t s . 6=2 4 b i t s . 10:8 SAMPL_SIZE[2:0] Determines the number of bits in a sample. Only the specified number of bits per sample are used. The value of any bits sent over the sample size will be 0. Default is 24 bits. 2 = 8 bits. 4=1 6 b i t s . 5=2 0 b i t s . 6=2 4 b i t s .

7 BITORDER

Determine if the MSB or LSB is transmitted first. Default is 0. 0 = Transmit MSB first. 1 = Transmit LSB first. 6S W A P SWAP—Swap position of the left and right channels. Default is 0. 0 = Transmit the left sample first. 1 = Transmit the right sample first. 5C L K I N V Inverts the data clock. Default is 0. 0 = The bit clock is not inverted. DFS will be captured on rising edge of DCLK. 1 = The bit clock is inverted. DFS will be captured on falling edge of DCLK. 4:1 FRAMING_MODE[3:0] Determines when the data is transmitted relative to frame sync. 0x0 = I 2S mode. 0x6 = DSP mode. 0x7 = Left-justified DSP mode. 0x8 = Left-justified mode. 0x9 = Right-justified mode. 0 Reserved Always write 0.

50 Rev. 0.3 Property 0x0202 DIGITAL_IO_OUTPUT_SAMPLE_RATE The DIGITAL_IO_OUTPUT_SAMPLE_RATE property sets the digital output sample rate in units of Hz. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 48000 Units: Hz DIGITAL_IO_OUTPUT_SAMPLE_RATE 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 OUTPUT_SAMPLE_RATE[15:0] 0xBB80 Bit Name Function 15:0 OUTPUT_SAMPLE_RATE[15:0] Sets the digital output sample rate in units of Hz. Default is 48000. Range is 32000–48000.

Rev. 0.3 51 Property 0x0203 DIGITAL_IO_OUTPUT_FORMAT The DIGITAL_IO_OUTPUT_FORMAT property configures di gital audio output format. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0x3600 DIGITAL_IO_OUTPUT_FORMAT 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 0x0 SLOT_SIZE[2:0] SAMPL_SIZE[2:0] BI TORDER SWAP CLKINV FRAMING_MODE[3:0] 0 Bit Name Function 15:14 Reserved Always write 0. 13:11 SLOT_SIZE[2:0] Defines the width of the data channel. This is only used in right-justified modes. 2 = 8 bits. 4=1 6 b i t s . 5=2 0 b i t s . 6=2 4 b i t s . 10:8 SAMPL_SIZE[2:0] Determines the number of bits in a sample. Only the specified number of bits per sample are used. The value of any bits sent over the sample size will be 0. Default is 24 bits. 2 = 8 bits. 4=1 6 b i t s . 5=2 0 b i t s . 6=2 4 b i t s . Determine if the MSB or LSB is transmitted first. Default is 0. 0 = Transmit MSB first. 1 = Transmit LSB first. 6S W A P SWAP—Swap position of the left and right channels. Default is 0. 0 = Transmit the left sample first. 1 = Transmit the right sample first. 5C L K I N V Inverts the data clock. Default is 0. 0 = The bit clock is not inverted. DFS will be captured on rising edge of DCLK. 1 = The bit clock is inverted. DFS will be captured on falling edge of DCLK. 4:1 FRAMING_MODE[3:0] Determines when the data is transmitted relative to frame sync. 0x0 = I 2S mode. 0x6 = DSP mode. 0x7 = Left-justified DSP mode. 0x8 = Left-justified mode. 0x9 = Right-justified mode. 0 Reserved Always write 0.

52 Rev. 0.3 Property 0x0300 AUDIO_ANALOG_VOLUME The AUDIO_ANALOG_VOLUME property sets the analog audio volume. A value of 0 will mute the audio; a value of 1 applies 62 dB of attenuation, and a value of 63 applies no attenuation. Each step accounts for 1 dB of change in the output. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 63 Property 0x0301 AUDIO_MUTE The AUDIO_MUTE property mutes/unmutes each audio output (analog left or analog right).The CTS bit (and optional interrupt) is set when it is sa fe to send the next command. This property may only be set or read when in the powerup mode. Default: 0x0000 AUDIO_ANALOG_VOLUME 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 0x000 VOL[5:0] 0x000 0x3F Bit Name Function 15:6 Reserved Always write 0. 5:0 VOL[5:0] Sets the analog audio volume. Default is 63. Range is 0–63. AUDIO_MUTE 1 5 1 4 1 3 1 2 1 1 1 0 98765432 1 0 0x0000 RIGHTMUTE LEFTMUTE 0x0000 0 0 Bit Name Function 15:2 Reserved Always write 0. 1 RIGHTMUTE 0 = Right audio is not muted. 1 = Right audio is muted. 0 LEFTMUTE 0 = Left audio is not muted. 1 = Left audio is muted.

Rev. 0.3 53 Property 0x0600 ZIF_OUTPUT_CFG (Si4777 Only) The ZIF_OUTPUT_CFG property enables/disables ZIF and co nfigures the ZIF interface format. The ZIF data rate depends on RCLK and the radio's operational mode. Changes to this property will take effect at tune time. The ZIF pins must also be configured, see ZIF_PIN_CFG on page 40. Refer to the Si477x data sheet for details on interface format and data rates. The CTS bit (and optio nal interrupt) is set when it is safe to send the next command. This property may only be sent in power-up mode. Default: 0x0801 ZIF_OUTPUT_CFG 1 5 1 41 3 1 2 1 1 1 0 9876 5 4321 0 FILL[1:0] RESERVED[7:0] FAL L ZIF_FORMAT[3:0] RESERVED 0x0 0x20 0 0x0 1 Bit Name Function 15:14 FILL[1:0] FILL[1:0]—Defines the fill value for unused data bits. Default 0. 0 = The unused bits are filled with 0s. 1 = The unused bits are filled with 1s. 2 = The unused bits are sign extended. 3 = The unused bits are filled with a random sequence. 13:6 RESERVED[7:0] Always write as 0x20 5F A L L FALL—IQCLK invert. Default 0. 0 = Output data changes concurrently with the falling edge of IQCLK. 1 = Output data changes concurrently with the rising edge of IQCLK. 4:1 ZIF_FORMAT[3:0] Default: 0x0 0x0 = I 2S ZIF format (Default). 0x8 = Left-justified ZIF format. 0x9 = Right-justified ZIF format. 0xE = DSP ZIF format . 0xF = DSP Left-justified ZIF format. 0 RESERVED Always write 1.

Table 14. FM Receiver Command Summary 0x30 FM_TUNE_FREQ Tunes the FM receiver to a frequency in 10 kHz steps. 0x32 FM_RSQ_STATUS Returns status informat ion about the received signal quality. Table 15. FM Receiver Property Summary Sets the FM Receive de-emphasis. Sets the maximum soft mute attenuation. Sets the SNR threshold for soft mute to start. Sets the maximum soft mute attack time in ms.

Table 15. FM Receiver Property Summary (Continued)

Enables the ACF interrupt sources. Sets the softmute interrupt threshold in dB. Sets the controlling metric for ACF features.

Control property for IBOC Blend (Si4777 only). 0x0100 Sets the digital audio static linear gain factor. Controls the multipath channel equalizer. Sets the stereo blend attack time in ms. Sets the stereo blend release time in ms.

Sets the stereo blend attack time in ms. Sets the stereo blend release time in ms. Sets the stereo blend attack time in ms. Sets the stereo blend release time in ms. Sets the high cut attack time in ms. Sets the high cut release time in ms. Sets the high cut attack time in ms. Sets the high cut release time in ms.

Sets the high cut attack time in ms. Sets the high cut release time in ms. Sets the high blend attack time in ms. Sets the high blend cut release time in ms. Sets the high blend attack time in ms. Sets the high blend release time in ms. Sets the high blend attack time in ms. Sets the high blend release time in ms. Configures interrupt related to RDS.

62 Rev. 0.3 9.2.1. FM Receiver Commands Command 0x30 FM_TUNE_FREQ The FM_TUNE_FREQ command sets the FM Receiver to tune to a frequency between 64 and 108 MHz in 10 kHz units. The CTS bit (and optional interrupt) is set when it is safe to send the next command. The ERR bit (and optional interrupt) is set if an invalid argument is sent. Note that only a single interrupt occurs if both the CTS and ERR bits are set. The optional STC interrupt is set when the command completes. This command may only be sent in powerup mode. The command clears the STC bit if it is already set. Command Bit 7 6 5 4 3 2 1 0 CMD 0x30 ARG1 0 HD TUNEMODE[1:0] 0 SMOOTHMETRICS 0 ARG2 FREQH[7:0] ARG3 FREQL[7:0] ARG Bit Name Function 17 R e s e r v e d Always write 0.

16 H D

Places the part in the HD mode. 0 = Normal Bandwidth. 1 = Wide-Bandwidth/HD Mode. 1 5:4 TUNEMODE[1:0] Sets the desired tuning mode. 0 = Validated normal tune: Unconditionally stay on the new channel after tune, tune status is valid. 1 = Invalidated fast tune: Unconditionally stay on the new channel after tune, tune status invalid. 13 R e s e r v e d Always write 0.

12 SMOOTH-

Smoothly transition audio state after tune. 0 = Initialize audio state to match this new channel. 1 = Transition audio state from previous channel values to the new channel values. 1 1:0 Reserved Always write 0. 27 : 0 F R E Q H[7:0] Tune Frequency High Byte. This byte in combination with FREQL selects the tune frequency in units of 10 kHz. In FM mode the valid range is from 6400 to 10800 (64–108 MHz). 37 : 0 F R E Q L[7:0] Tune Frequency Low Byte. This byte in combination with FREQH selects the tune frequency in units of 10 kHz. In FM mode, the valid range is from 6400 to 10800 (64–108 MHz).

Rev. 0.3 63 Response Command 0x31 FM_SEEK_START The FM_SEEK_START command begins searching for a valid station. In order for a station to be considered valid, each of the following thresholds must be met: FM_VALID_SNR_THRESHOLD and FM_VALID_RSSI_THRESHOLD and FM_VALID_MAX_TUNE_ERROR. Clears any pending STCINT, RSQINT, or RDSINT interrupt status. Seek can be cancelled through setting the CANCEL bit in the FM_RSQ_STATUS command. The CTS bit (and optional interrupt) is set when it is safe to send the next command. The ERR bit (and optional interrupt) is set if an invalid argument is sent. Note that only a si ngle interrupt occurs if both the CTS and ERR bits are set. The optional STC interrupt is set when the command completes. This command may only be sent in powerup mode. The command clears the STCINT bit if it is already set. Command Response B i t 76543210 STATUS CTS ERR XX RSQINT RDSINT ACFINT STCINT B i t 76543210 CMD 0x31 ARG1 0000 SEEKUP WRAP 00 ARG Bit Name Function 1 7:4 Reserved Always write 0. 1 3 SEEKUP Seek Up/Down. Determines the direction of the search, either UP = 1, or DOWN = 0.

12 W R A P

Wrap/Halt. Determines whether the seek should Wrap = 1, or Halt = 0 when it hits the band limit. 1 1:0 Reserved Always write 0. B i t 76543210 STATUS CTS ERR XX RSQINT RDSINT ACFINT STCINT

64 Rev. 0.3 Command 0x32 FM_RSQ_STATUS The FM_RSQ_STATUS command returns status information about the received signal quality. This command returns the Received Signal Strength Indicator (RSSI), Signal to Noise Ratio (SNR), Adjacent Channel Strength for 200 kHz (ASSI), Adjacent Channel Strength for 100 kHz (LASSI and HA SSI), frequency offset (FREQOFF), Multipath (MULT) and Ultrasonic Noise (USN) associated with the desired channel. It also indicates valid channel (VALID) and AFC rail status (AFCRL). This command can be used to check if the received signal is above the RSSI high threshold as reported by RSSIHINT or below the RSSI low threshold as reported by RSSILINT. It can also be used to check if the signal is above the SNR high threshold as reported by SNRHINT or below the SNR low threshold as reported by SNRLINT. It can be used to check if the detected multipat h is above the Multipath high threshold as reported by MULTHINT or below the Multipath low threshold as reported by MULTLINT. The command clears the RSQINT, BLENDINT, SNRHIN T, SNRLINT, RSSIHINT, RSSILINT, MULTHINT, and MULTLINT interrupt bits when the RSQACK bit of ARG1 is set. If the condition is still true after the interrupt is cleared, another interrupt will fire assuming that bit is enabled in FM_RSQ_INTERRUPT_SOURCE. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This command may only be sent when in powerup mode. FM_RSQ_ STATUS Command 76543210 CMD 0x32 ARG1 000 0 RSQACK ATTUNE CANCEL STCACK ARG Bit Name Function 1 7:5 Reserved Always write 0. 1 4 Reserved Always write 0. 1 3 RSQACK Clears RSQINT, SNRHINT, SNRLINT, RSSIHINT, RSSILINT, BLENDINT, MULTHINT, and MULTLINT if set. 1 2 ATTUNE Returns the values of metrics as of tune time. When the AT_TUNE bit is set, values returned for RSQ_STATUS are the values calculated at tune and do not change unless another FM_TUNE_FREQ command is called. This feature can be used to determine why seek stopped at the current station. 1 1 CANCEL Aborts a seek or tune currently in progress. 0 = Don't abort. 1 = Abort. 1 0 STCACK Clears the STC interrupt status indicator if set.

Rev. 0.3 65 Response Bit 7 6 5 4 3 2 1 0 STATUS CTS ERR XX RSQINT RDSINT ACFINT STCINT RESP1 MULTHINT MULTLINT X X SNRHINT SNRLINT RSSIHINT RSSILINT RESP 2 BLTF X SNRREADY RSSIREADY X X AFCRL VALID RESP 3 READFREQ[15:8] RESP 4 READFREQ[7:0] RESP 5 FREQOFF[7:0] RESP 6 RSSI[7:0] RESP 7 SNR[7:0] RESP 8 XXXXXXXX RESP 9 LASSI[7:0] RESP 10 HASSI[7:0] RESP 11 MULT[7:0] RESP 12 DEV[7:0] RESP 13 XX RESP 14 XX RESP 15 ASSI200[7:0] RESP 16 USN[7:0] RESP 17 PILOTDEV[7:0] RESP 18 RDSDEV[7:0] RESP 19 ASSI200DEV[7:0] RESP 20 STRONGDEV[7:0] RESP 21 RDSPI[15:8] RESP 22 RDSPI[7:0]

66 Rev. 0.3 RESP Bit Name Function 1 7 MULTHINT Multipath Detect High. 0 = Indicates that multipath value has not exceeded the Multipath high threshold set by FM_RSQ_MULTIPATH_HIGH_THRESHOLD. 1 = Indicates that multipath value has exceeded the Multipath high threshold set by FM_RSQ_MULTIPATH_HIGH_THRESHOLD. 1 6 MULTLINT Multipath Detect Low. 0 = Indicates that multipath value has not fallen below the Multipath low threshold set by FM_RSQ_MULTIPATH_LOW_THRESHOLD. 1 = Indicates that multipath value has fallen below the Multipath low threshold set by FM_RSQ_MULTIPATH_LOW_THRESHOLD. 1 5:4 Reserved Values may vary.

13 S N R H I N T

SNR Detect High. 0 = Indicates that the received signal SNR has not exceeded the SNR high threshold set by FM_RSQ_SNR_HIGH_THRESHOLD 1 = Indicates that the received signal SNR has exceeded the SNR high threshold set by FM_RSQ_SNR_HIGH_THRESHOLD.

12 S N R L I N T

SNR Detect Low. 0 = Indicates that the received signal SNR has not fallen below the SNR low threshold set by FM_RSQ_SNR_LOW_THRESHOLD. 1 = Indicates that the received signal SNR has fallen below the SNR low threshold set by FM_RSQ_SNR_LOW_THRESHOLD. 1 1 RSSIHINT RSSI Detect High. 0 = Indicates that the received signal RSSI has not exceeded the RSSI high threshold set by FM_RSQ_RSSI_HIGH_THRESHOLD. 1 = Indicates that the received signal RSSI has exceeded the RSSI high threshold set by FM_RSQ_RSSI_HIGH_THRESHOLD. 1 0 RSSILINT RSSI Detect Low. 0 = Indicates that the received signal RSSI has not fallen below the RSSI low threshold set by FM_RSQ_RSSI_LOW_THRESHOLD. 1 = Indicates that the received signal RSSI has fallen below the RSSI low threshold set by FM_RSQ_RSSI_LOW_THRESHOLD.

Rev. 0.3 67 27 BLTF Band Limit. Reports if a seek hits the band limit (WRAP = 0 in FM_START_SEEK) or wrapped to the original fre- quency (WRAP = 1). 26 Reserved Values may vary. 2 5 SNR READY The SNRREADY and RSSIREADY bits indicate that the RSSI/SNR have been read as a result of a tune command. If either one of these bits are 0 this indicates that either the metric is being measured (because a tune is in progress) or that the metric was not mea- sured during tune because the station was invalidated before the metric could be measured. In the case where a metric was not measured during tune, the tune time RSQ status will read back as 0 for the unmea- sured metric. The normal running time status for these metrics is not affected and will report normally. 0 = SNR measurement in progress (tune in progress) or not taken (tune completed). 1 = SNR measurement ready. 2 4 RSSIREADY The SNRREADY and RSSIREADY bits indicate that the RSSI/SNR have been read as a result of a tune command. If either one of these bits are 0 this indicates that either the metric is being measured (because a tune is in progress) or that the metric was not mea- sured during tune because the station was invalidated before the metric could be measured. In the case where a metric was not measured during tune, the tune time RSQ status will read back as 0 for the unmea- sured metric. The normal running time status for these metrics is not affected and will report normally. 0 = RSSI measurement in progress (tune in progress) or not taken (tune completed). 1 = RSSI measurement ready. 23 : 2 R e s e r v e d Values may vary. 21 A F C R L Set if the AFC rails. AFC gets railed if FREQOFF > MAX_TUNE_ERROR.

20 V A L I D Reports if the channel is valid based on the settings of

FM_VALID_RSSI_THRESHOLD, FM_VALID_SNR_- THRESHOLD, FM_VALID_MAX_TUNE_ERROR 3,4 15:0 READFREQ[15:0] Returns the currently tuned frequency. 5 7:0 FREQOFF[7:0] Signed frequency offset in units of 2 ppm (–128 to 127) 6 7:0 RSSI[7:0] Received Signal Strength indicator in dBµV (–128 to 127) 7 7:0 SNR[7:0] RF SNR indicator in dB (–128 to 127). 87 : 0 R e s e r v e d Values may vary. RESP Bit Name Function

68 Rev. 0.3 9 7:0 LASSI[7:0] Low side Adjacent (100 kHz) Channel Strength Indica- tor reports the (Signal + Noise) power relative to the carrier.(–128 to 127) 10 7:0 HASSI[7:0] High side Adjacent (100 kHz) Channel Strength Indica- tor reports the (Signal + Noise) power relative to the carrier.(–128 to 127) 11 7:0 MULT[7:0] Multipath indicator (0–127%). 12 7:0 DEV[7:0] Frequency Deviation metric in kHz. 13, 14 15:0 Reserved Values may vary. 15 7:0 ASSI200[7:0] Adjacent Channel (±200 kHz) Strength Indicator reports the (Signal + Noise) power relative to the car- rier. This metric reports the sum of high and low adja- cent channel strengths. (–128 to 127) 16 7:0 USN[7:0] Ultrasonic Noise Indicator in –dBFS (0 to 127). 127 corresponds to 127 dB down from full scale. 17 7:0 PILOTDEV[7:0] Pilot deviation in units of 100 Hz. 18 7:0 RDSDEV[7:0] RDS deviation in units of 100 Hz. 19 7:0 ASSI200DEV[7:0] Adjacent Channel (±200 kHz) Deviation in units of 1.45 kHz. 20 7:0 STRONGDEV[7:0] Deviation of strong desired signals. This is an alterna- tive to DEV, which can become erroneous in the pres- ence of very strong signals. Approximately, deviation in kHz = STRONGDEV x f(mod), where f(mod) is 5.55 kHz for mono signals or 2.75 kHz for stereo signals 21, 22 15:0 RDSPI[15:0] RD S PI code. RESP Bit Name Function

Rev. 0.3 69 Command 0x35 FM_ACF_STATUS The FM_ACF_STATUS command returns status informat ion about automatically-controlled features. This command returns the Soft Mute Attenuation, Channel Filt er Bandwidth, Hi-cut cutoff frequency, Hi-blend cutoff frequency, and Stereo Separation associated with the desired channel. Stereo Separation will only be non-zero if the pilot indicator is set. If SMUTE bi t is high, it indicates that audio is soft-muted. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This command may only be sent in powerup mode. Command Response B i t 76543210 CMD 0x35 ARG1 0000000 ACFACK ARG Bit Name Function 1 7:1 Reserved Always write 0. 1 0 ACFACK If set clears ACFINT and any ACF interrupts bits. Bit 7 6 5 4 3 2 1 0 STATUS CTS ERR XX RSQINT RDSINT ACFINT STCINT RESP1 XXX BLEND_INT HIBLEND_INT HICUT_INT CHBW_INT SOFTMUTE_INT RESP2 XXXXXXX SMUTE RESP3 XXX SMATTN[4:0] RESP4 CHANBW[7:0] RESP5 HICUT[7:0] RESP6 HIBLEND[7:0] RESP7 PILOT STBLEND[6:0] RESP8 LOWCUT[7:0]

70 Rev. 0.3 RESP Bit Name Function 1 7:5 Reserved Values may vary. 1 4 BLEND_INT If set, indicates that stereo separation has crossed below the blend threshold set by FM_ACF_BLEND_THRESHOLD. 1 3 HIBLEND_INT If set, indicates that the HiBlend cutoff frequency is lower than the threshold as set by FM_ACF_HIBLEND_THRESHOLD. 1 2 HICUT_INT If set, indicates that the HiCut cutoff frequency is lower than the threshold set by FM_ACF_HICUT_THRESHOLD. 11C H B W _ I N T If set, indicates that the Channel Filter Bandwidth is less than the threshold set by ACF_CHBW_THRESHOLD. 1 0 SOFTMUTE_INT If set, indicates that softmute attenuation has increased above the softmute threshold as set by ACF_SM_THRESHOLD. 2 7:1 Reserved Values may vary. 20 S M U T E 0 = Audio is not soft muted. 1 = Audio is soft muted. 37 : 0 S M A T T N [ 7 : 0 ] Soft mute attenuation level in dB. Range: 0–31. 4 7:0 CHANBW[7:0] Channel filter bandwidth in kHz. Range: 0–150. 57 : 0H I C U T [ 7 : 0 ] HiCut cutoff frequency in units of 100 Hz. Range: 10–180. 6 7:0 HIBLEND[7:0] HiBlend cutoff frequency in units of 100 Hz. Range: 10–180. 77 P I L O T 0 = Stereo pilot is not present. 1 = Stereo pilot is present. 7 6:0 STBLEND[6:0] Indicates stereo separation. STBLEND will only be non-zero if PILOT = 1. Range 0–100. 7 7:0 LOWCUT[7:0] Lowcut cutoff freque ncy in units of 10 Hz. Range 1–100.

Rev. 0.3 71 Command 0x36 FM_RDS_STATUS The FM_RDS_STATUS command returns RDS information for current channel and reads an entry from the RDS FIFO. RDS information includes synch status, FIFO status , group data (blocks A, B, C, and D), and block errors corrected. Maximum RDS FIFO size is 25 groups. This command clears the RDSINT interrupt bit when INTACK bit in ARG1 is set, and, if MTF IFO is set, the entire RDS receive FIFO is cleared (FIFO is always cleared during FM_TUNE_FREQ or FM_SEEK_START). The CT S bit (and optional inte rrupt) is set when it is safe to send the next command. This command may only be sent in powerup mode. Command B i t 76543210 CMD 0x36 ARG1 00000 STA- TUS_ONL Y MTFIFO INTACK ARG Bit Name Function 1 7:3 Reserved Always write 0.

12 S T A T U S _ O N L Y

Status Only. Determines if data should be removed from the RDS FIFO. 0 = Data is removed from RDS FIFO, and RDSFIFOUSED decre- ments by one. Data in BLOCKA, BLOCKB, BLOCKC, BLOCKD, and BLE contain the oldest data in the RDS FIFO. 1 = Data is not removed from RDSFIFO, and the RDSFIFOUSED value stays the same. Data in BLOCKA, BLOCKB, BLOCKC, BLOCKD, BLE, PI, TP, PTY, and status contain the last valid data received for the current station. 1 1 MTFIFO Empty FIFO. The FIFO will always be cleared during FM_TUNE_FREQ and FM_SEEK_START. 0 = If FIFO not empty, read and remove oldest FIFO entry. 1 = Clear RDS Receive FIFO.

10 I N T A C K

Interrupt Acknowledge. 0 = RDSINT status preserved. 1 = Clears RDSINT.

72 Rev. 0.3 Response B i t 7 6 5 4 3 210 STATUS CTS ERR XX RSQINT RDSINT ACFINT STCINT RESP1 XXX RDSTPPTYINT RDSPIINT X RDSSYNCINT RDS- FIFOINT RESP2 XXX TPPTYVALID PIVALID X RDSSYNC RDSFIFO- LOST RESP3 XX TP PTY[4:0] RESP4 PI[15:8] RESP5 PI[7:0] RESP6 RDSFIFOUSED[7:0] RESP7 BLEA[1:0] BLEB[1:0] BL EC[1:0] BLED[1:0] RESP8 BLOCKA[15:8] RESP9 BLOCKA[7:0] RESP10 BLOCKB[15:8] RESP11 BLOCKB[7:0] RESP12 BLOCKC[15:8] RESP13 BLOCKC[7:0] RESP14 BLOCKD[15:8] RESP15 BLOCKD[7:0]

Rev. 0.3 73 RESP Bit Name Function 1 7:5 Reserved Values may vary.

14 R D S T P P T Y I N T 1 = TP (Traffic Program) flag and/or PTY (Program Type) code

has changed. 1 3 RDSPIINT 1 = PI (Program Identification) code has changed. 1 2 Reserved Values may vary. 1 1 RDSSYNCINT 1 = RDS synchr onization has changed. 1 0 RDSFIFOINT 1 = RDS was received and the RDS FIFO is full or has atleast FM_RDS_INTERRUPT_FIFO_COUNT entries. 2 7:5 Reserved Values may vary. 2 4 TPPTYVALID 1 = Indicates that TP flag and PTY code are valid. 2 3 PIVALID 1 = Indicates that PI code is valid. 2 2 Reserved Values may vary. 2 1 RDSSYNC 1 = RDS is curr ently synchronized. 2 0 RDSFIFOLOST 1 = Indicates that one or more RDS groups have been discarded due to FIFO overrun since last call to FM_RDS_STATUS. 3 7:6 Reserved Values may vary. 3 5 TP Current channel’s TP flag if TPPTYVALID is set to 1. 3 4:0 PTY[4:0] Current channel's PT Y code if TPPTYVALID is 1. 4,5 15:0 PI[15:0] Current channel’s PI code if PIVALID is set to 1. 6 7:0 RDSFIFOUSED[7:0] RDS FIFO Used. Number of groups remaining in the RDS FIFO (0 if empty). If non-zero, BLOCKA-BLOCKD contain the oldest FIFO entry and RDSFIFOUSED decrements by one on the next call to RDS_FI- FO_STATUS (assuming no RDS data received in the interim). 7 7:6 BLEA[1:0] RDS Block A Corrected Errors. 0 = No errors. 1 = 1–2 bit errors detected and corrected. 2 = 3–5 bit errors detected and corrected. 3 = Uncorrectable. 7 5:4 BLEB[1:0] RDS Block B Corrected Errors. 0 = No errors. 1 = 1–2 bit errors detected and corrected. 2 = 3–5 bit errors detected and corrected. 3 = Uncorrectable. 7 3:2 BLEC[1:0] RDS Block C Corrected Errors. 0 = No errors. 1 = 1–2 bit errors detected and corrected. 2 = 3–5 bit errors detected and corrected. 3 = Uncorrectable.

74 Rev. 0.3 7 1:0 BLED[1:0] RDS Block D Corrected Errors. 0 = No errors. 1 = 1–2 bit errors detected and corrected. 2 = 3–5 bit errors detected and corrected. 3 = Uncorrectable. 8,9 15:0 BLOCKA[15:0] Block A group data from oldest FIFO entry if STATUSONLY is 0. Last valid Block A data if STATUSONLY is 1. 10,11 15:0 BLOCKB[15:0] Block B group data from oldest FIFO entry if STATUSONLY is 0. Last valid Block A data if STATUSONLY is 1. 12,13 15:0 BLOCKC[15:0] Block C group data from oldest FIFO entry if STATUSONLY is 0. Last valid Block A data if STATUSONLY is 1. 14,15 15:0 BLOCKC[15:0] Block D group data from oldest FIFO entry if STATUSONLY is 0. Last valid Block A data if STATUSONLY is 1. RESP Bit Name Function

Rev. 0.3 75 Command 0x37 FM_RDS_BLOCKCOUNT The FM_RDS_BLOCKCOUNT command returns RDS expect ed, received, and uncorrectable block statistic information. Reset info by setting CLEAR bit or sending FM_TUNE_FREQ or FM_SEEK_START commands. Once EXPECTED saturates at 65535, all other block count statistics will be frozen until the counts are cleared. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This command may only be sent when in powerup mode. Command Response B i t 76543210 CMD 0x37 ARG1 0000000 CLEAR ARG Bit Name Function 1 7:1 Reserved Always write 0. 1 0 CLEAR Clears the block counts if set. The current block counts will be reported before they are cleared. B i t 76543210 STATUS CTS ERR XX RSQINT RDSINT ACFINT STCINT RESP1 XXXXXXXX RESP 2 EXPECTED[15:8] RESP 3 EXPECTED[7:0] RESP 4 RECEIVED[15:8] RESP 5 RECEIVED[7:0] RESP 6 UNCORRECTABLE[15:8] RESP 7 UNCORRECTABLE[7:0] RESP Bit Name Function 1 7:0 Reserved Values may vary. 2,3 15:0 EXPECTED[15:0] Number of expected RDS blocks. 4,5 15:0 RECEIVED[15:0] Number of received RDS blocks. Under ideal conditions, EXPECTED and RECEIVED would be identical. The difference between these two numbers is the number of blocks lost. 6,7 15:0 UNCORRECTABLE[15:0] Number of uncorrectable RDS blocks. These blocks have been received, but were found to have uncorrectable errors. The block error rate (BLER) is calculated by: BLER = (UNCORRECTABLE + (EXPECTED-RECEIVED)) / EXPECTED

76 Rev. 0.3 9.2.2. FM Receiver Properties Property 0x0302 AUDIO_DE_EMPHASIS The AUDIO_DE_EMPHASIS property sets the FM Receive de-emphasis to 50 or 75 μs. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. The default is 75 μs. Default: 0 Property 0x0400 FM_SOFT_MUTE_MAX_ATTENUATION The FM_SOFT_MUTE_MAX_ATTENUATION property sets the maximum attenuation in dB that will be applied by the softmute feature. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 8 Units: dB AUDIO_DE_EMPHASIS 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 0x0000 DE_EMPH 0x0000 0 Bit Name Function 15:1 Reserved Always write 0.

0 DE_EMPH

Sets the FM Receive de-emphasis to 50 or 75 μs. Default is 75 µs. 0=7 5µ s e c 1=5 0µ s e c FM_SOFT_MUTE_MAX_ATTENUATION 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 0x000 SMATTN[6:0] 0x000 0x08 Bit Name Function 15:5 Reserved Always write 0. 4:0 SMATTN[6:0] Sets the maximum attenuation in dB that will be applied by the softmute feature. Default is 8 dB. Range is 0–63 dB.

Rev. 0.3 77 Property 0x0401 FM_SOFT_MUTE_TRIGGER_THRESHOLD The FM_SOFT_MUTE_TRIGGER_THRESHOLD property sets the SNR threshold in dB to engage softmute. The CTS bit (and optional interrupt) is set when it is sa fe to send the next command. If USE_RSSI is set in FM_ACF_CONTROL_SOURCE property, then property 0x0401 refers to RSSI threshold. This property may only be set or read in powerup mode. Default: 8 Units: dB (dBµV if RSSI is used as the control source) Property 0x0402 FM_SOFT_MUTE_END_THRESHOLD The FM_SOFT_MUTE_END_THRESHOLD property sets the SNR threshold in dB at which softmute attenuation will be set to its maximum va lue. When the SNR is at this level or lo wer, the audio attenuation will be set to FM_SOFT_MUTE_MAX_ATTENUATION. The CTS bit (and optional interrupt) is set when it is safe to send the next command. If USE_RSSI is set in the FM_ACF_CONTROL_SOURCE property, then property 0x0402 refers to the RSSI threshold. This property may only be set or read in powerup mode. Default: 0 Units: dB (dBµV if RSSI is used as the control source) FM_SOFT_MUTE_TRIGGER_THRESHOLD 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 0x00 SMTRGTH[7:0] 0x00 0x08 Bit Name Function 15:8 Reserved Always write 0. 7:0 SMTRGTH[7:0] Sets the SNR threshold in dB to engage softmute. Default is 8 dB. Range is –127 to 127 dB (dBµV if RSSI is used as the con- trol source). FM_SOFT_MUTE_END_THRESHOLD 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 0x00 SMENDTH[7:0] 0x00 0x00 Bit Name Function 15:8 Reserved Always write 0. 7:0 SMENDTH[7:0] Sets the SNR threshold in dB at which softmute attenuation will be set to its maximum value given by FM_SOFT_MUTE_MAX_ATTENUATION prop- erty. Default is 0 dB. Range is –127 to 127 dB (dBµV if RSSI is used as the control source).

78 Rev. 0.3 Property 0x0403 FM_SOFT_MUTE_RELEASE_TIME The FM_SOFT_MUTE_RELEASE_TIME property sets the maximum time in ms it takes to unmute the audio. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 500 Units: ms Property 0x0404 FM_SOFT_MUTE_ATTACK_TIME The FM_SOFT_MUTE_ATTACK_TIME property sets the maximum time in ms it takes to mute the audio. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 120 Units: ms FM_SOFT_MUTE_RELEASE_TIME 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 RELEASE[15:0] 0x01F4 Bit Name Function 15:0 RELEASE[15:0] Sets the maximum time in ms it takes to unmute the audio. Default is 500 ms. Range is 1–32767 ms. Note that there will be 16 ms of filter delay for the RSSI/SNR metric before softmute can engage/disen- gage. FM_SOFT_MUTE_ATTACK_TIME 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 ATTACK[15:0] 0x0078 Bit Name Function 15:0 ATTACK[15:0] Sets the maximum time in ms it takes to mute the audio. Default is 120 ms. Range is 1–32767 ms. Note that there will be 16 ms of filter delay for the RSSI/SNR metric before softmute can engage/disen- gage.

Rev. 0.3 79 Property 0x0700 FM_AGC_FE_CONFIG The FM_AGC_FE_CONFIG property specifies the input path for the RF signal and other FE configuration options. This property should only be set before the first tune. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Changes to this property take effect after the next tune is completed. Default: 0 FM_AGC_FE_CONFIG 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 0x00 FMLNAZ FMMIX 0x0 Reserved INPUTSELECT[3:0] 0x00 0 0 0x0 0 0x0 Bit Name Function 15:9 Reserved Always write 0. 8F M L N A Z 0 = Normal LNA mode where the LNA input impedance is 50 . 1 = LNA loopthru mode where LNA input impedance is 100  7F M M I X 0 = Mixer is differential input (FMXIP/FMXIN) 1 = Mixer is single ended (FMXIP) 6:4 Reserved Always write 0. 3:0 INPUTSELECT[3:0] 0 = Received signal comes into FMI pin, out FMO and then the mixer pin. 1 = Received signal comes directly into the mixer.

80 Rev. 0.3 Property 0x0701 FM_AGC_PD_CONFIG The FM_AGC_PD_CONFIG property specifies behavior of the FM peak detectors and attenuators. This property should only be set before the first tune. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This command may only be sent in powerup mode. Changes to this property take effect after the next tune is completed. Default: 0x0270 FM_AGC_PD_CONFIG 1 5 1 4 1 3 1 2 1 1 1 0 9 8 7654 3 2 1 0 0x0 LNA_MODE 00100 MIXER_PD[2:0] 0x00 LNA_PD[1:0] 0x0 0 00100 0x7 0x00 0x00 Bit Name Function 15:13 Reserved Always write 0.

12 LNA_MODE

LNA_MODE default: 0 This property only used when the LNA gain and one or both of the attenuators are controlled by the same peak detector. 0 = Reduce LNA gain and then attenuate. 1 = Attenuate and then reduce LNA gain. 11:7 Reserved Always write 00100. 6:4 MIXER_PD[2:0] MIXER_PD[2:0] default: 0x7. 0 = Peak detector not used. 1 = Controls FMAGC1. 2 = Controls FMAGC2. 3 = Controls FMAGC1 and FMAGC2. 4 = Controls LNA gain. 5 = Controls LNA gain and FMAGC1. 6 = Controls LNA gain and FMAGC2. 7 = Controls LNA gain, FMAGC1 and FMAGC2. 3:2 Reserved Always write 0. 1:0 LNA_PD[1:0] LNA_PD[1:0] default: 0x0 0 = Peak detector not used 1 = Controls FMAGC1 2 = Controls FMAGC2 3 = Controls FMAGC1 and FMAGC2

Rev. 0.3 81 Property 0x0702 FM_LNA_AGC_ATTACK_MS The FM_LNA_AGC_ATTACK_MS property sets the number of milliseconds the wide-band RF high-peak detector must be exceeded before attenuating the appropriate block. The peak detectors are only sampled once every 3 to 5 ms. If the peak detector trips, the internal counter is in cremented by 4 ms.The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 4 Units: ms Property 0x0703 FM_LNA_AGC_RELEASE_MS The FM_LNA_AGC_RELEASE_MS property sets the number of milliseconds the wideband RF low-peak detector must not be exceeded before increasing the gain of the appropriate block. The peak detectors are only sampled once every 3 to 5 ms. If the peak de tector trips, the internal counter is incremented by 4 ms. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 80 Units: ms FM_LNA_AGC_ATTACK_MS 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 RF_AGC_ATTACK_MS[15:0] 0x04 Bit Name Function 15:0 RF_AGC_ATTACK_MS[15:0] Number of milliseconds the wideband RF high- peak detector must be exceeded before atten- uating the appropriate block. Default is 4 ms. Range is 4–4096 ms. FM_LNA_AGC_RELEASE_MS 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 RF_AGC_RELEASE_MS[15:0] 0x50 Bit Name Function 15:0 RF_AGC_RELEASE_MS[15:0] Number of milliseconds the wideband RF low-peak detector must not be exceeded before increasing the gain of the appropriate block. Default is 80 ms Range is 4–4096 ms.

82 Rev. 0.3 Property 0x0704 FM_LNA_AGC_PD_THRESHOLD The FM_LNA_AGC_PD_THRESHOLD property sets the high threshold and hysteresis for the LNA peak detector. The high threshold sets the level at which the AGC increa ses attenuation. The hysteresis is how many dB below the high threshold the level must drop before the AGC decreases attenuation. It is possible to decrease the likelihood of intermod break-in by decreasing the peak detector threshold from the default and it is possible to decrease the likelihood of desensitization by increasing the peak detector threshold. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0x4F05 FM_LNA_AGC_PD_THRESHOLD 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 HIGH[7:0] HYST[7:0] 0x4F 0x05 Bit Name Function 15:8 HIGH[7:0] Sets the level in dBµV at which AGC increases attenuation HIGH[7:0] Range: 73–87 73 = 73 dBµV 75 = 75 dBµV 77 = 77 dBµV 79 = 79 dBµV 81 = 81 dBµV 83 = 83 dBµV 85 = 85 dBµV 87 = 87 dBµV 7:0 HYST[7:0] Sets how many dB below the high threshold the level must drop before the AGC decreases attenuation. HYST[7:0] Range: 3–6 3 = 3 dB 4 = 4 dB 5 = 5 dB 6 = 6 dB

Rev. 0.3 83 Property 0x0705 FM_MIXER_AGC_ATTACK_MS The FM_MIXER_AGC_ATTACK_MS property sets th e number of millis econds the wideband mixer high-peak detector must be exceeded before attenuating the appropriate block. The peak detectors are only sampled once every 3–5 ms. If the peak detector trips, the internal co unter is incremented by 4 ms. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 4 Units: ms Property 0x0706 FM_MIXER_AGC_RELEASE_MS The FM_MIXER_AGC_RELEASE_MS property sets the nu mber of milliseconds the wideband mixer low-peak detector must not be exceeded before increasing the gain of the appropriate block. The peak detectors are only sampled once every 3–5 ms. If the peak detector trips, th e internal counter is incremented by 4 ms. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 80 Units: ms FM_MIXER_AGC_ATTACK_MS 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 MIX_AGC_ATTACK_MS[15:0] 0x04 Bit Name Function 15:0 MIX_AGC_ATTACK_MS[15:0] Number of milliseconds the wideband RF high- peak detector must be exceeded before atten- uating the appropriate block. Default is 4 ms Range is 4–4096 ms. FM_MIXER_AGC_RELEASE_MS 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 MIX_AGC_RELEASE_MS[15:0] 0x50 Bit Name Function 15:0 MIX_AGC_RELEASE_MS[15:0] Number of milliseconds the wideband RF low-peak detector must not be exceeded before increasing the gain of the appropriate block. Default is 80 ms Range is 4–4096 ms.

84 Rev. 0.3 Property 0x0707 FM_MIXER_AGC_PD_THRESHOLD The FM_MIXER_AGC_PD_THRESHOLD property sets the high threshold and hysteresis for the mixer peak detector. The high threshold sets the level at which the AGC increases attenuation. The hysteresis is how many dB below the high threshold the level must drop before the AGC decreases attenuation. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0x5503 FM_MIXER_AGC_PD_THRESHOLD 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 HIGH[7:0] HYST[7:0] 0x55 0x03 Bit Name Function 15:8 HIGH[7:0] Sets the level in dBµV at which AGC increases attenuation. HIGH[7:0]: Range 79–93. 79 = 79 dBµV. 81 = 81 dBµV. 83 = 83 dBµV. 85 = 85 dBµV. 87 = 87 dBµV. 89 = 89 dBµV. 91 = 91 dBµV. 93 = 93 dBµV. 7:0 HYST[7:0] Sets how many dB below the high threshold the level must drop before the AGC decreases attenuation. HYST[7:0] - Range: 3–6. 3 = 3 dB. 4 = 4 dB. 5 = 5 dB. 6 = 6 dB.

Rev. 0.3 85 Property 0x0710 FM_AGC_OVERRIDE The FM_AGC_OVERRIDE property overrides the AGC settin g by disabling the AGC and forcing the gain to be maximum. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0x0000 Property 0x1100 FM_SEEK_BAND_BOTTOM The FM_SEEK_BAND_BOTTOM property se ts the bottom of the FM band fo r seek. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. The default is 87.5 MHz. Default: 8750 Units: 10 kHz FM_AGC_OVERRIDE 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 0x000 AGC_OVERRIDE[5:0] 0x000 0 Bit Name Function 15:6 Reserved Always write 0. 5:0 AGC_OVERRIDE[5:0] AGC_OVERRIDE selects whether the AGC is enabled or disabled. 0 = AGC is enabled. 0x3F = AGC is disabled and set to maximum gain. FM_SEEK_BAND_BOTTOM 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 FMSKFREQL[15:0] 0x222E Bit Name Function 15:0 FMSKFREQL[15:0] Sets the bottom of the FM band for seek. Default is 8750. Range: 6400–10800, 64.0 MHz to 108.0 MHz. Range: 8750–10790, Worldwide FM excluding Japan. Range: 6580–7400, OIRT FM. Range: 7600–9000, Japan FM.

86 Rev. 0.3 Property 0x1101 FM_SEEK_BAND_TOP The FM_SEEK_BAND_TOP property sets the top of the FM band for seek. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. The default is 107.9 MHz Default: 10790 Units: 10 kHz Property 0x1102 FM_SEEK_FREQUENCY_SPACING The FM_SEEK_FREQUENCY_SPACING pr operty selects frequency spacin g for FM seek. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. The default is 100 kHz. Default: 10 Units: 10 kHz FM_SEEK_BAND_TOP 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 FMSKFREQH[15:0] 0x2A26 Bit Name Function 15:0 FMSKFREQH[15:0] Sets the top of the FM band for seek. Default is 10790. Range: 6400–10800, 64.0 MHz to 108.0 MHz. Range: 8750–10790, Worldwide FM excluding Japan. Range: 6580–7400, OIRT FM. Range: 7600–9000, Japan FM. FM_SEEK_FREQUENCY_SPACING 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 0x000 FMSKSPACE[4:0] 0x000 0x0A Bit Name Function 15:5 Reserved Always write 0. 4:0 FMSKSPACE[4:0] Selects frequency spacing for FM seek. Default is 10. Range is 1–31.

Rev. 0.3 87 Property 0x1200 FM_RSQ_INTERRUPT_SOURCE The FM_RSQ_INTERRUPT_SOURCE property configures in terrupt related to Receiv ed Signal Quality metrics. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. The default is 0. Default: 0 FM_RSQ_INTERRUPT_SOURCE 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 0x00 MULTHINT MULTLINT 0 SNRHINT SNRLINT RSSIHINT RSSILINT 0x00 0 0 0 0 0 0 0 Bit Name Function 15:8 Reserved Always write 0. 7M U L T H I N T 0: Disable Interrupt. 1:Enable interrupt if Multipath level goes above the threshold set by FM_RSQ_- MULTIPATH_HIGH_THRESHOLD. 6M U L T L I N T 0: Disable Interrupt. 1: Enable interrupt if Multipath level falls below the threshold set by FM_RSQ_- MULTIPATH_LOW_THRESHOLD. 5:4 Reserved Always write 0.

3 SNRHINT

0: Disable Interrupt. 1: Enable interrupt if SNR goes above the threshold set by FM_RSQ_SN- R_HIGH_THRESHOLD. 2S N R L I N T 0: Disable Interrupt. 1: Enable interrupt if SNR falls below the threshold set by FM_RSQ_SN- R_LOW_THRESHOLD.

1 RSSIHINT

0: Disable Interrupt. 1: Enable interrupt if RSSI goes above the threshold set by FM_R- SQ_RSSI_HIGH_THRESHOLD.

0 RSSILINT

0: Disable Interrupt. 1: Enable interrupt if RSSI falls below the threshold set by FM_R- SQ_RSSI_LOW_THRESHOLD.

88 Rev. 0.3 Property 0x1201 FM_RSQ_SNR_HIGH_THRESHOLD The FM_RSQ_SNR_HIGH_THRESHOLD property sets the high threshold, which triggers the RSQ interrupt if the SNR is above this threshold. The CTS bit (and optional interr upt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 127 Units: dB Property 0x1202 FM_RSQ_SNR_LOW_THRESHOLD The FM_RSQ_SNR_LOW_THRESHOLD property sets low threshold, which triggers the RSQ interrupt if the SNR is below this threshold. The CTS bit (and optional interrup t) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: –128 Units: dB FM_RSQ_SNR_HIGH_THRESHOLD 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 0x00 SNRH[7:0] 0x00 0x7F Bit Name Function 15:8 Reserved Write 0 for (+) values and 0xFF for (–) values. 7:0 SNRH [7:0] Sets the high threshold, which triggers the RSQ interrupt if the SNR is above this threshold. Default is 127 dB. Range is –128 to 27 in steps of 1 dB. FM_RSQ_SNR_LOW_THRESHOLD 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 0xFF SNRL[7:0] 0xFF 0x80 Bit Name Function 15:8 Reserved Write 0 for (+) values and 0xFF for (–) values. 7:0 SNRL [7:0] Sets low threshold, which triggers the RSQ interrupt if the SNR is below this threshold. Default is –128 dB. Range is –128 to 127 in steps of 1 dB.

Rev. 0.3 89 Property 0x1203 FM_RSQ_RSSI_HIGH_THRESHOLD The FM_RSQ_RSSI_HIGH_THRESHOLD property sets the high threshold, which triggers the RSQ interrupt if RSSI is above this threshold. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 127 Units: dBµV Property 0x1204 FM_RSQ_RSSI_LOW_THRESHOLD The FM_RSQ_RSSI_LOW_THRESHOLD property sets low threshold, which triggers the RSQ interrupt if the RSSI is below this threshold. The CTS bit (and optional interrup t) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: –128 Units: dBµV FM_RSQ_RSSI_HIGH_THRESHOLD 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 0x00 RSSIH[7:0] 0x00 0x7F Bit Name Function 15:8 Reserved Write 0 for (+) values and 0xFF for (–) values. 7:0 RSSIH [7:0] Sets high threshold, which triggers the RSQ interrupt if the RSSI is above this threshold. Default is 127 dBµV. Range is –128 to 127 in steps of 1 dB. FM_RSQ_RSSI_LOW_THRESHOLD 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 0xFF RSSIL[7:0] 0xFF 0x80 Bit Name Function 15:8 Reserved Write 0 for (+) values and 0xFF for (–) values. 7:0 RSSIL [7:0] Sets low threshold, which triggers the RSQ interrupt if the RSSI is below this threshold. Default is –128 dBµV. Range is –128 to 127 in steps of 1 dB.

90 Rev. 0.3 Property 0x1207 FM_RSQ_MULTIPATH_HIGH_THRESHOLD The FM_RSQ_MULTIPATH_HIGH_THRESHOLD property sets the high threshold, which triggers the RSQ interrupt if Multipath is above this threshold. Multipath is a measure of AM modulation and can exceed 100%. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 127 Property 0x1208 FM_RSQ_MULTIPATH_LOW_THRESHOLD The FM_RSQ_MULTIPATH_LOW_THRESHOLD property sets low threshold, which triggers the RSQ interrupt if Multipath is below this thre shold. Multipath is a measure of AM modu lation and can exceed 100%. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0 FM_RSQ_MULTIPATH_HIGH_THRESHOLD 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 0x000 MULTH[6:0] 0x000 0x7F Bit Name Function 15:7 Reserved Always write 0. 6:0 MULTH [6:0] Sets the high threshold, which triggers the RSQ interrupt if Multipath is above this threshold. Default is 127. Range is 0–127. FM_RSQ_MULTIPATH_LOW_THRESHOLD 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 0x000 MULTL[6:0] 0x000 0x00 Bit Name Function 15:7 Reserved Always write 0. 6:0 MULTL[6:0] Sets low threshold, which triggers the RSQ interrupt if Multipath is below this threshold. Default is 0. Range is 0–127.

Rev. 0.3 91 Property 0x1300 FM_ACF_INTERRUPT_SOURCE The FM_ACF_INTERRUPT_SOURCE property enables the AC F interrupt sources. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0 FM_ACF_INTERRUPT_SOURCE 1 5 1 4 1 3 1 21 11 098765 4 3 2 1 0 0x000 BLEND_INT HIBLEND_INT HICUT _INT CHBW_INT SOFTMUTE_INT 0x000 00 0 0 0 Bit Name Function 15:5 Reserved Always write 0. 4B L E N D _ I N T When set, enables the blend interrupt. Default is 0. 0 = The blend interrupt is disabled. 1 = The blend interrupt is enabled.

3 HIBLEND_INT

When set, enables the Hi-blend Interrupt. Default is 0. 0 = The Hi-blend interrupt is disabled. 1 = The Hi-blend interrupt is enabled.

2 HICUT_INT

When set, enables the Hi-cut interrupt. Default is 0. 0 = The Hi-cut interrupt is disabled. 1 = The Hi-cut interrupt is enabled.

1 CHBW_INT

When set, enables the Channel Filter Bandwidth Interrupt. Default is 0. 0 = The Channel Filter Bandwidth interrupt is disabled. 1 = The Channel Filter Bandwidth interrupt is enabled.

0 SOFTMUTE_INT

When set, enables the blend interrupt. Default is 0. 0 = The softmute interrupt is disabled. 1 = The softmute interrupt is enabled.

92 Rev. 0.3 Property 0x1301 FM_ACF_SM_THRESHOLD The FM_ACF_SM_THRESHOLD property sets the softmute in terrupt threshold in dB. When softmute attenuation rises above the level set by this property and the SOFTMUTE_INT interrupt is enabled through the FM_ACF_INTERRUPT_SOURCE property , the SOFTMUTE_INT inte rrupt will be assert ed. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in the powerup mode. Default: 31 Units: dB FM_ACF_SM_THRESHOLD 1 5 1 4 1 3 1 2 1 1 1 0 9 8 7 6 5 43210 0x000 SMATTN_THRESH[4:0] 0x000 0x1F Bit Name Function 15:5 Reserved Always write 0. 4:0 SMATTN_THRESH[4:0] Softmute interrupt threshold in dB, which triggers the softmute interrupt when the softmute attenuation rises above this level. Default is 31 dB Range is 0–31 dB.

Rev. 0.3 93 Property 0x1302 FM_ACF_CHBW_THRESHOLD The FM_ACF_CHBW_THRESHOLD property sets the Channel Filter Bandwidth interrupt threshold in units of kHz. When the channel filter bandwidth falls below this thre shold and the CHBW_INT interrupt is enabled through the FM_ACF_INTERRUPT_SOURCE property, the CHBW_INT interrup t will be asserted. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0 Units: kHz FM_ACF_CHBW_THRESHOLD 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 0x00 CHBW_THRESH[7:0] 0x00 0x00 Bit Name Function 15:8 Reserved Always write 0. 7:0 CHBW _THRESH[7:0] Channel Filter Bandwidth interrupt threshold in units of kHz, which triggers the Channel Filter Bandwidth Interrupt when the channel filter bandwidth falls below this threshold. Default is 0 kHz Range is 0–255 kHz.

94 Rev. 0.3 Property 0x1303 FM_ACF_HICUT_THRESHOLD The FM_ACF_HICUT_THRESHOLD property sets the Hi-cut interrupt threshold in units of 100 Hz. When the Hi- cut cutoff frequency falls below this threshold and the HICUT_INT interrupt is enabled through the FM_ACF_INTERRUPT_SOURCE property, the HICUT_INT interrupt will be asse rted. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0 Units: 100 Hz FM_ACF_HICUT_THRESHOLD 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 0x00 HICUT_THRESH[7:0] 0x00 0x00 Bit Name Function 15:8 Reserved Always write 0. 7:0 HICUT_THRESH[7:0] Hi-cut interrupt threshold in units of 100 Hz, which triggers the Hi-cut Inter- rupt when the Hi-cut cutoff frequency falls below this threshold. Default is 0. Range is 0–200.

Rev. 0.3 95 Property 0x1304 FM_ACF_HIBLEND_THRESHOLD The FM_ACF_HIBLEND_THRESHOLD property sets the HiBlend interrupt threshold in units of 100 Hz. When the Hi-blend cutoff frequency falls belo w this threshold and the HIBLEND_INT interrupt is enabled through the FM_ACF_INTERRUPT_SOURCE property , the HIBLEND_INT interrupt will be asserted. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0 Units: 100 Hz FM_ACF_HIBLEND_THRESHOLD 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 0x00 HIBLEND_THRESH[7:0] 0x00 0x00 Bit Name Function 15:8 Reserved Always write 0. 7:0 HIBLEND_THRESH[7:0] Hi-blend interrupt threshold in units of 100 Hz, which triggers the Hi-blend Interrupt when the Hi-blend cutoff frequency falls below this threshold. Default is 0. Range is 0–200.

96 Rev. 0.3 Property 0x1305 FM_ACF_BLEND_THRESHOLD The FM_ACF_BLEND_THRESHOLD property sets the interrupt trigger threshold for stereo blend. The threshold is expressed as a percentage in terms of L minus R (L – R) gain factor K. When the L–R gain falls below this threshold and the BLEND_INT is enabled through the FM_ACF_INTERRUPT_SOURCE property, the BLEND_INT will be asserted. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Note: Stereo Separation S = (1 + K) / (1 – K), where K is the L minus R gain factor. Stereo separation of 1 implies mono mode and stereo separation of >1 implies that the part is in ster eo with up to 20 log(S) dB of st ereo separation. This property expresses the threshold value of K as a percentage. For example, value 0x0032 = a K of 50%, or a stereo separation of Default: 0 Units: % L-R gain FM_ACF_BLEND_THRESHOLD 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 0x000 BLEND_THRESH[6:0] 0x000 0x00 Bit Name Function 15:7 Reserved Always write 0. 6:0 BLEND_ THRESH [6:0] Stereo Blend Interrupt threshold in units of % L-R gain, which triggers the Blend threshold interrupt when L-R gain falls below this threshold. Default is 0%. Range is 0–100%.

Rev. 0.3 97 Property 0x1306 FM_ACF_CONTROL_SOURCE The FM_ACF_CONTROL_SOURCE property determines the controlling metric for ACF features. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 1 FM_ACF_CONTROL_SOURCE 1 5 1 4 1 3 1 2 1 1 1 0 9 87654 3 2 1 0 0x0000 AFC_SM 0 RSSI_SM 0x0000 00 1 Bit Name Function 15:1 Reserved Always write 0. 2A F C _ S M default: 0. When set, softmute will be triggered by an AFC rail. 0 = Do not use AFC rail to force a softmute. 1 = Use AFC rail to force a softmute. 1 Reserved Always write 0.

0 RSSI_SM

default: 1. When set, RSSI will be used inst ead of SNR as the controlling metric for softmute. 0 = Use SNR as the controlling metric for softmute. 1 = Use RSSI as the controlling metric for softmute.

98 Rev. 0.3 Property 0x2000 FM_VALID_MAX_TUNE_ERROR The FM_VALID_MAX_TUNE_ERROR property sets the maximum freq error allowed in units of 2 ppm before setting the AFC rail indicator (AFCRL). The CTS bit (and opti onal interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 75 (150 ppm) Units: 2 ppm Property 0x2001 FM_VALID_RSSI_TIME The FM_VALID_RSSI_TIME property sets the amount of time in milliseconds to allow the RSSI metric to settle before evaluating. This parameter is valid only if TUNEMODE[1:0] (FM_TUNE_FREQ) is set to 0. The minimum RSSI settling delay is 3 milliseconds. The reliability of the valid bit for identifying valid stations relies on this parameter being set properly. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 6 Units: ms FM_VALID_MAX_TUNE_ERROR 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 0x00 FMMAXTUNEERR[7:0] 0x00 0x4B Bit Name Function 15:8 Reserved Always write 0. 7:0 FMMAXTUNEERR [7:0] Sets the maximum freq error allowed in units of 2 ppm before setting the AFC rail indicator (AFCRL). Default is 75. Range is 0–126. FM_VALID_RSSI_TIME 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 0x00 SSIVALTIME[7:0] 0x00 0x06 Bit Name Function 15:8 Reserved Always write 0. 7:0 SSIVALTIME[7:0] Validation time in milliseconds. Default is 6 ms. Range is 3–63 ms.

Rev. 0.3 99 Property 0x2002 FM_VALID_SNR_TIME The FM_VALID_SNR_TIME property sets the amount of time in milliseconds to allow the SNR metric to settle before evaluating. This parameter is valid only if TUNEMODE[1:0] (FM_TUNE_FREQ) is set to 0. The minimum SNR settling delay is 4 ms. The reliability of the valid bit for identifying valid stations relies on this parameter being set properly. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 18 Units: ms Property 0x2003 FM_VALID_SNR_THRESHOLD The FM_VALID_SNR_THRESHOLD property sets the SNR th reshold for a valid FM Seek/Tune. If the desired channel SNR is above this threshold, then it is considered valid. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 8 Units: dB FM_VALID_SNR_TIME 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 0x00 SNRVALTIME[7:0] 0x00 0x12 Bit Name Function 15:8 Reserved Always write 0. 7:0 SNRVALTIME[7:0] Validation time in milliseconds. Default is 18 ms. Range is 4–63 ms. FM_VALID_SNR_THRESHOLD 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 0x00 FMVALSNR[7:0] 0x00 0x08 Bit Name Function 15:8 Reserved Write 0 for (+) values and 0xFF for (–) values. 7:0 FMVALSNR [7:0] Sets the SNR threshold for a valid FM Seek/Tune. Default is 8 dB. Range is –128 to 127 in steps of 1 dB. –128 = SNR is not used as a criterion in determining the validity of a station.

100 Rev. 0.3 Property 0x2004 FM_VALID_RSSI_THRESHOLD The FM_VALID_RSSI_THRESHOLD property sets the RSSI threshold for a valid FM Seek/Tune. If the desired channel RSSI is above this threshold, then it is considered valid. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 12 Units: dBµV Property 0x200A FM_VALID_ASSI_THRESHOLD The FM_VALID_ASSI_THRESHOLD propert y sets the ASSI threshold for valid FM Seek/Tune. If the desired channel ASSI is below this threshold, then it is considered valid. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0x503C Units: ms FM_VALID_RSSI_THRESHOLD 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 0x00 FMVALRSSI[7:0] 0x00 0x0C Bit Name Function 15:8 Reserved Always write 0. 7:0 FMVALRSSI[7:0] Sets the RSSI threshold for a valid FM Seek/Tune. Default is 12 dBµV. Range is –128 to 127 in steps of 1 dB. –128 = RSSI is not used as a criterion in determining the validity of a station. FM_VALID_ASSI_THRESHOLD 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 FMVALASSI200[6:0] 0 FMVALASSI100[6:0] 0x50 0 0x3C Bit Name Function 15 Reserved Always write 0. 14:8 FMVALASSI200[6:0] Sets the ASSI200 threshold for valid FM Seek/Tune. Default is 80 dB. Range is 0 to 127 dB. 7 Reserved Always write 0. 6:0 FMVALASSI100[6:0] Sets the max(HASSI,LASSI) threshold for valid FM Seek/Tune. Default is 60 dB. Range is 0 to 127 dB.

Rev. 0.3 101 Property 0x2200 FM_CHBW_SQ_MIN_MAX The FM_CHBW_SQ_MIN_MAX property sets the maximum and minimum channel filter bandwidth in kHz based on RSSI. To force a given channel filter bandwidth, se t the min and max to the same value. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0x9637 Units: kHz Property 0x2201 FM_CHBW_SQ_HIGH_THRESHOLD The FM_CHBW_SQ_HIGH_THRESHOLD property sets the RSSI/deviation threshold for maximum channel filter bandwidth. This engine is only enabled when RSSI is above the FM_CHBW_WEAKSIG_THR. If the instantaneous RSSI is greater than or equal to the programmed RSSI high threshold then the channel filter bandwidth will be set to the maximum value programmed through Property 0x2200. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 12 Units: dBµV FM_CHBW_SQ_MIN_MAX 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 MAX[7:0] MIN[7:0] 0x96 0x37 Bit Name Function 15:8 MAX [7:0] Sets the maximum channel filter bandwidth in kHz. Default is 150 kHz Range is 1–150 kHz. 7:0 MIN [7:0] Sets the minimum channel filter bandwidth in kHz. Default is 55 kHz. Range is 1–150 kHz. FM_CHBW_SQ_HIGH_THRESHOLD 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 RSSIMAX[15:0] 0x000C Bit Name Function 15:0 RSSIMAX[15:0] Sets the RSSI threshold for maximum channel filter bandwidth. Default is 12 dBµV Range is –128 to 127 dBµV.

102 Rev. 0.3 Property 0x2202 FM_CHBW_SQ_LOW_THRESHOLD The FM_CHBW_SQ_LOW_THRESHOLD property sets the RSSI threshold for minimum channel filter bandwidth. This engine is only enabled when RSSI is above t he FM_CHBW_WEAKSIG_THR. If the instantaneous RSSI is less than or equal to the programmed RSSI low thre shold then the channel filter bandwidth will be set to the minimum value programmed through Property 0x2200. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: –4 Units: dBµV Property 0x2203 FM_CHBW_SQ_WIDENING_TIME The FM_CHBW_SQ_WIDENING_TIME property sets the chan nel filter bandwidth widening time based on RSSI. This engine is only enabled when RSSI is above the FM_CHBW_WEAKSI G_THR. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 16 Units: ms FM_CHBW_SQ_LOW_THRESHOLD 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 RSSIMIN[15:0] 0xFFFC Bit Name Function 15:0 RSSIMIN[15:0] Sets the RSSI threshold for minimum channel filter bandwidth. Default is –4 dBµV Range is 128 to –127 dBµV. FM_CHBW_SQ_WIDENING_TIME 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 WIDENING_TIME[15:0] 0x0010 Bit Name Function 15:0 WIDENING_TIME[15:0] Sets the RSSI based channel filter bandwidth widening time. Default is 16 ms Range is 1–32767 ms.

Rev. 0.3 103 Property 0x2204 FM_CHBW_SQ_NARROWING_TIME The FM_CHBW_SQ_NARROWING_TIME property sets the c hannel filter bandwidth narrowing time based on RSSI. This engine is only enabl ed when RSSI is above the FM_ CHBW_WEAKSIG_THR. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 2048 Units: ms FM_CHBW_SQ_NARROWING_TIME 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 NARROWING_TIME[15:0] 0x0800 Bit Name Function 15:0 NARROWING_TIME[15:0] Sets the RSSI based channel filter bandwidth narrowing time. Default is 2048 ms. Range is 1–32767 ms.

104 Rev. 0.3 Property 0x2205 FM_CHBW_ASSI_MIN_MAX The FM_CHBW_ASSI_MIN_MAX property sets the maximu m and minimum Channel Filter Bandwidth in kHz based on 100 kHz blocker delta (difference between HASSI and LASSI). To force a given channel filter bandwidth, set the min and max to the same value. The CTS bit (and op tional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0x9623 Units: kHz Property 0x2206 FM_CHBW_ASSI_LOW_THRESHOLD The FM_CHBW_ASSI_LOW_THRESHOLD property sets the 100 kHz blocke r delta (difference between HASSI and LASSI) threshold for maximum channel filter bandwidth. If the 100 kHz blocker delta is less than or equal to the programmed ASSI low threshold, then the channel filter bandwidth will be set to the maximum value programmed through Property 0x2205. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This command may only be sent in powerup mode. Default: 7 Units: dB FM_CHBW_ASSI_MIN_MAX 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 MAX[7:0] MIN[7:0] 0x96 0x23 Bit Name Function 15:8 MAX [7:0] Sets the maximum channel filter bandwidth in kHz. Default is 150 kHz. Range is 1–150 kHz. 7:0 MIN [7:0] Sets the minimum channel filter bandwidth in kHz. Default is 35 kHz. Range is 1–150 kHz. FM_CHBW_ASSI_LOW_THRESHOLD 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 ASSIMIN[15:0] 0x0007 Bit Name Function 15:0 ASSIMIN[15:0] Sets the 100 kHz blocker delta threshold for maximum channel filter bandwidth. Default is 7 dB. Range is –128 to 127 dB.

Rev. 0.3 105 Property 0x2207 FM_CHBW_ASSI_HIGH_THRESHOLD The FM_CHBW_ASSI_HIGH_THRESHOLD property sets the 100 kHz blocker delta (difference between HASSI and LASSI) threshold for mini mum channel filter bandwidth. If the 100 k Hz blocker delta is greater than the programmed ASSI high threshold, then the channel filter bandwidth will be set to the minimum value programmed through Property 0x2205. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This command may only be sent in powerup mode. Default: 20 Units: dB Property 0x2208 FM_CHBW_ASSI_WIDENING_TIME The FM_CHBW_ASSI_WIDENING_TIME property sets the ch annel filter bandwidth wi dening time based on the 100 kHz blocker delta (difference between HASSI and LASSI). The CTS bit (and optional interrupt) is set when it is safe to send the next command. This command may only be sent in powerup mode. Default: 3200 Units: ms FM_CHBW_ASSI_HIGH_THRESHOLD 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 ASSIMAX[15:0] 0x0014 Bit Name Function 15:0 ASSIMAX[15:0] Sets the 100 kHz blocker delta threshold for minimum channel filter bandwidth. Default is 20 dB. Range is –128 to 127 dB. FM_CHBW_ASSI_WIDENING_TIME 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 WIDENING_TIME[15:0] 0x0C80 Bit Name Function 15:0 WIDENING_TIME[15:0] Sets the 100 kHz blocker delta based channel filter bandwidth widening time. Default is 3200 ms. Range is 1–32767 ms.

106 Rev. 0.3 Property 0x2209 FM_CHBW_ASSI_NARROWING_TIME The FM_CHBW_ASSI_NARROWING_TIME property sets the ch annel filter bandwidth narrowing time based on the 100 kHz blocker delta (difference between HASSI and LASSI). The CTS bit (and optional interrupt) is set when it is safe to send the next command. This command may only be sent in powerup mode. Default: 320 Units: ms Property 0x220A FM_CHBW_ASSI200_MIN_MAX The FM_CHBW_ASSI200_MIN_MAX property sets the maximum and minimum channel filter bandwidth in kHz based on 200 kHz blocker strength. To force a given chan nel filter bandwidth, set the min and max to the same value. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0x9650 Units: kHz FM_CHBW_ASSI_NARROWING_TIME 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 NARROWING_TIME[15:0] 0x0140 Bit Name Function 15:0 NARROWING_TIME[15:0] Sets the 100 kHz blocker delta based channel filter band- width narrowing time. Default is 320 ms. Range is 1–32767 ms. FM_CHBW_ASSI200_MIN_MAX 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 MAX[7:0] MIN[7:0] 0x96 0x50 Bit Name Function 15:8 MAX[7:0] Sets the maximum channel filter bandwidth in kHz. Default is 150 kHz. Range is 1–150 kHz. 7:0 MIN[7:0] Sets the minimum channel filter bandwidth in kHz. Default is 80 kHz. Range is 1–150 kHz.

Rev. 0.3 107 Property 0x220B FM_CHBW_ASSI200_LOW_THRESHOLD The FM_CHBW_ASSI200_LOW_THRESHOLD property sets the 200 kHz blocker strength threshold for maximum channel filter bandwidth. If the 200 k Hz blocker strength is less than or equal to the pr ogrammed ASSI200 low threshold, then the channel filter bandwidth will be set to the maximum value pr ogrammed thro ugh Property 0x220A. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This command may only be sent in powerup mode. Default: –10 Units: dB relative to desired channel RSSI Property 0x220C FM_CHBW_ASSI200_HIGH_THRESHOLD The FMCHBW_ASSI200_HIGH_THRESHOLD property sets the 200 kHz blocker strength threshold for minimum channel filter bandwidth. If the 200 kHz blocker strength is greater than the programmed ASSI200 high threshold, then the channel filter bandwidth will be set to the minimum value programmed through Property 0x220A. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This command may only be sent in powerup mode. Default: 10 Units: dB relative to desired channel RSSI FM_CHBW_ASSI200_LOW_THRESHOLD 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 ASSI200MIN[7:0] 0xFFF6 Bit Name Function 15:0 ASSI200MIN[15:0] Sets the 200 kHz blocker strength threshold for maximum channel filter bandwidth. Default is –10 dB (relative to desired channel RSSI) Range is –128 to 127 dBr. FM_CHBW_ASSI200_HIGH_THRESHOLD 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 ASSI200MAX[7:0] 0x000A Bit Name Function 15:0 ASSI200MAX[15:0] Sets the 200 kHz blocker strength threshold for maximum channel filter bandwidth. Default is 10 dB (relative to desired channel RSSI) Range is –128 to 127 dBr.

108 Rev. 0.3 Property 0x220D FM_CHBW_ASSI200_WIDENING_TIME The FM_CHBW_ASSI200_WIDENING_TIME property sets the channel filter bandwidth widening time based on the 200 kHz blocker strength. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This command may only be sent in powerup mode. Default: 3200 Units: ms Property 0x220E FM_CHBW_ASSI200_NARROWING_TIME The FM_CHBW_ASSI200_NARROWING_TIME property sets th e channel filter bandwi dth narrowing time based on the 200 kHz blocker strength. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This command may only be sent in powerup mode. Default: 320 Units: ms FM_CHBW_ASSI200_WIDENING_TIME 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 WIDENING_TIME[15:0] 0x0C80 Bit Name Function 15:0 WIDENING_TIME[15:0] Sets the 200 kHz blocker strength based channel filter bandwidth widening time. Default is 3200 ms. Range is 1–32767 ms. FM_CHBW_ASSI200_NARROWING_TIME 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 NARROWING_TIME[15:0] 0x0140 Bit Name Function 15:0 NARROWING_TIME[15:0] Sets the 200 kHz blocker strength based channel filter band- width narrowing time. Default is 320 ms. Range is 1–32767 ms.

Rev. 0.3 109 Property 0x220F FM_CHBW_WEAKSIG_THR The FM_CHBW_WEAKSIG_THR prop erty sets the RSSI value at wh ich the engine w ill engage (LOW) and disengage (HIGH) for the weak signal channel filter bandwidth engine. Default: 0x100D Property 0x3105 FM_LOWCUT_MIN_FREQ The FM_LOWCUT_MIN_FREQ property sets the minimum cutoff frequency. The LowCut tracks the HICUT engine; therefore, thresholds are programmed in HICUT threshold properties (0x3600, 0x3604, 0x3608, 0x360C, 0x3610, 0x3614) and the HIBLEND threshold properties (0x3700, 0x3740, 0x3708, 0x370C, 0x3710, 0x3714). Setting the property to 0 disables LowCut. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0 Units: Hz FM_CHBW_WEAKSIG_THR 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 HIGH[7:0] LOW[7:0] 0x10 0x0D Bit Name Function 15:8 HIGH[7:0] When RSSI is above this value, the weak signal channel filter bandwidth engine dis- engages. Default: 0x10. 7:0 LOW[7:0] When RSSI is below this value, the weak signal channel filter bandwidth engine engages. Default: 0x0D. FM_LOWCUT_MIN_FREQ 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 FREQ_MIN[15:0] 0x0000 Bit Name Function 15:0 FREQ_MIN[15:0] Sets the minimum LOW-CUT cutoff frequency in Hz. Default is disabled. Range is 8–1000 Hz. 0=D i s a b l e d .

110 Rev. 0.3 Property 0x3106 FM_LOWCUT_MAX_FREQ The FM_LOWCUT_MAX_FREQ property sets the maximum cutoff frequency. The LowCut tracks the HICUT engine, therefore thresholds are programmed in HICUT threshold properties (0x3600, 0x3604, 0x3608, 0x360C, 0x3610, 0x3614) and the HIBLEND threshold properties (0x3700, 0x3740, 0x3708, 0x370C, 0x3710, 0x3714). The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0 Units: Hz FM_LOWCUT_MIN_FREQ 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 FREQ_MAX[15:0] 0x0000 Bit Name Function 15:0 FREQ_MAX[15:0] Sets the maximum LOW-CUT cutoff frequency in Hz. Note that if property 0x3105 (FM_LOWCUT_MIN_FREQ) is non- zero, this property must be set to a value no less than prop- erty 0x3105. Default is 0 Hz. Range is 0–1000 Hz.

Rev. 0.3 111 Property 0x3300 FM_IBOC_CONTROL (Si4777 Only) The FM_IBOC_CONTROL property is the control proper ty for IBOC Blend. DIGITAL_IO_INPUT_SAMPLE_RATE and DIGITAL_IO_INPUT_FORMAT must be configured before IBOC Blend will function. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0x0000 Property 0x3301 FM_IBOC_ANALOG_TO_HD_CROSSFADE_TIME (Si4777 Only) The FM_IBOC_ANALOG_TO_HD_CROSSFADE_TIME property sets the crossfade time between full analog and full HD Digital audio in ms. The CTS bit (and optional interrupt) is set when it is sa fe to send the next command. This property may only be set or read in powerup mode. Default: 1000 Units: ms FM_IBOC_CONTROL 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 0x00 FORCE 0x00 ENABLE 0x00 0 0x00 0 Bit Name Function 15:9 Reserved Always write 0.

8 FORCE

Forces IBOC Blend. Default is 0. 0 = Do not force IBOC blend. The audio source is determined by the IBOC con- trol pin. 1 = Force IBOC blend. The audio is sourced from the IBOC system 7:1 Reserved Always write 0.

0 ENABLE

ENABLE - IBOC Blend Enable. Default is 0. 0 = The IBOC Blend system is disabled. 1 = The IBOC Blend system is enabled. FM_IBOC_ANALOG_TO_HD_CROSSFADE_TIME 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 TIME[15:0] 0x03E8 Bit Name Function 15:0 TIME[15:0] Sets the full analog to full digital crossfade time in ms. Default is 1000 ms. Range is 0–22000 ms.

112 Rev. 0.3 Property 0x3302 FM_IBOC_HD_TO_ANALOG_CROSSFADE_TIME (Si4777 Only) The FM_IBOC_HD_TO_ANALOG_CROSSFADE_TIME property sets the crossfade time from full HD Digital to full analog audio in ms. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 1000 Units: ms Property 0x3303 FM_IBOC_DYNAMIC_GAIN (Si4777 Only) The FM_IBOC_DYNAMIC_GAIN property sets the digital audio dynamic linear scaling factor. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0x007F FM_IBOC_HD_TO_ANALOG_CROSSFADE_TIME 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 TIME[15:0] 0x03E8 Bit Name Function 15:0 TIME[15:0] Sets the full digital to full analog crossfade time in ms. Default is 1000 ms. Range is 0–22000 ms. FM_IBOC_DYNAMIC_GAIN 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 0x00 DGAIN[7:0] 0x00 0x7F Bit Name Function 15:8 Reserved Always write 0. 7:0 DGAIN[7:0] Station dependent linear scaling factor in Q7 format. Default is 0x7F. Range is 0–0x7F.

Rev. 0.3 113 Property 0x3304 FM_IBOC_STATIC_GAIN (Si4777 Only) The FM_IBOC_STATIC_GAIN property sets the digital audio static linear gain factor. Reverse the sign of this number to obtain a 180 degree phase shift. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read when in the powerup mode. Default: 0x0100 Property 0x3400 FM_MULT_EQ_CTL The FM_MULT_EQ_CTL property controls the multipath channel equalizer. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 5121 FM_IBOC_STATIC_GAIN 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 SGAIN[15:0] 0x0100 Bit Name Function 15:0 SGAIN[15:0] Static linear gain factor in Q7.8 format. Default is 0x0100. Range is 0x8000–0x7FFF. FM_MULT_EQ_CTL 1 5 1 4 1 3 1 2 1 1 1 0 98765432 1 0 0x00 NUM_TAPS[4:0] 0x00 MULT_EQ_CTL[1:0] 0x00 0x14 0x00 0x1 Bit Name Function 15:13 Reserved Always write 000. 12:8 NUM_TAPS[4:0] Number of taps in the multipath equalizer. Range 1-20. For automatic selec- tion, use 0. 7:2 Reserved Always write 000000. 1:0 MULT_EQ_CTL[1:0] Controls the Multipath channel equalizer. Default is 1 0 = Equalizer OFF 1 = Equalizer ON

114 Rev. 0.3 Property 0x3401 FM_EQ_NOISE_DISABLE_MULT_EQ The FM_EQ_NOISE_DISABLE_MULT_EQ property sets the RSSI threshold belo w which the ch annel equalizer will use noise measurements to enable /disable the channel equalizer. The CT S bit (and optional in terrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0xFC81 Property 0x3500 FM_BLEND_RSSI_THRESHOLDS The FM_BLEND_RSSI_THRESHOLDS property sets the RS SI thresholds for maximum and minimum stereo separation (set by Property 0x3501) on the blend engine. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0x3719 Units: dBµV FM_EQ_NOISE_DISABLE_MULT_EQ 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 MULT_EQ_ON_LEVEL[7:0] MULT_EQ_OFF_LEVEL[7:0] 0xFC 0x81 Bit Name Function 15:8 MULT_EQ_ON_LEVEL[7:0] RSSI level above which noise measurements will not be used to enable/disable the equalizer. Default: –4 (0xFC). 7:0 MULT_EQ_OFF_LEVEL[7:0] RSSI level below which noise measurements will be used to enable/disable the equalizer. Set to –127 (0x81) to disable. Default:0x81 (disabled) FM_BLEND_RSSI_THRESHOLDS 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 RSSIMAX[7:0] RSSIMIN[7:0] 0x37 0x19 Bit Name Function 15:8 RSSIMAX[7:0] Sets the RSSI Max threshold. If RSSI is above this threshold, maximum stereo separation will be achieved as set by property 0x3501. Default is 55 dBµV. Range is –20 to 120 dBµV. 7:0 RSSIMIN[7:0] Sets the RSSI Min threshold. If RSSI is below this threshold, minimum ste- reo separation will be achieved as set by property 0x3501. Default is 25 dBµV. Range is –20 to 120 dBµV.

Rev. 0.3 115 Property 0x3501 FM_BLEND_RSSI_STEREO_SEP The FM_BLEND_RSSI_STEREO_ SEP property sets the maximum and mi nimum stereo separation based on RSSI (set by Property 0x3500) on the blend engine. You can force a constant stereo separation value by setting ST_SEPMAX and ST_SEPMIN to the same value. To disable the stereo blend based on RSSI, set ST_SEPMAX = ST_SEPMIN = 100 (0x64.) The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0x2D00 Units: dB Property 0x3502 FM_BLEND_RSSI_ATTACK_TIME The FM_BLEND_RSSI_ATTACK_TIME property sets the tr ansition time for which the stereo blend mitigation engine decreases the stereo separation based on RSSI. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 16 Units: ms FM_BLEND_RSSI_STEREO_SEP 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 ST_SEPMAX[7:0] ST_SEPMIN[7:0] 0x2D 0x00 Bit Name Function 15:8 ST_SEPMAX[7:0] Sets the maxi mum stereo separation. Default is 45 dB. Range is 0–64 dB. 7:0 ST_SEPMIN[7:0] Sets the minimum stereo sepa ration. Default is 0 dB. Range is 0–64 dB. FM_BLEND_RSSI_ATTACK_TIME 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 ATTACK[15:0] 0x0010 Bit Name Function 15:0 ATTACK[15:0] Sets the transition time for which the stereo blend mitigation engine decreases the stereo separation based on RSSI. Default is 16 ms. Range is 1–32767 ms.

116 Rev. 0.3 Property 0x3503 FM_BLEND_RSSI_RELEASE_TIME The FM_BLEND_RSSI_RELEASE_ TIME property sets the transition time for which the ster eo blend mitigation engine increases the stereo separation based on RSSI. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 4000 Units: ms Property 0x3508 FM_BLEND_MULTIPATH_THRESHOLDS The FM_BLEND_MULTIPATH_THRESHOLDS property sets the Multipath thresholds for maximum and minimum stereo separation (set by Property 0x3509) on the blend engine. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0x1E3C FM_BLEND_RSSI_RELEASE_TIME 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 RELEASE[15:0] 0x0FA0 Bit Name Function 15:0 RELEASE[15:0] Sets the transition time for which the stereo blend mitigation engine increases the stereo separation based on RSSI. Default is 4000 ms. Range is 1–32767 ms. FM_BLEND_MULTIPATH_THRESHOLDS 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 MULTMIN[7:0] MULTMAX[7:0] 0x1E 0x3C Bit Name Function 15:8 MULTMIN[7:0] Sets the Multipath Min threshold. If Multipath is below this threshold, maxi- mum stereo separation will be achieved as set by property 0x3509. Default is 30. Range is 0–127. 7:0 MULTMAX[7:0] Sets the Multipath Max threshold. If Multipath is above this threshold, mini- mum stereo separation will be achieved as set by property 0x3509. Default is 60. Range is 0–127.

Rev. 0.3 117 Property 0x3509 FM_BLEND_MULTIPATH_STEREO_SEP The FM_BLEND_MULTIPATH_STEREO_SEP property sets the maximum and minimum stereo separation based on Multipath (set by Property 0x3508) on the blend engi ne. You can force a constant stereo separation value by setting ST_SEPMAX and ST_SEPMIN to the same value. To disable the stereo blend based on Multipath, set ST_SEPMAX = ST_SEPMIN = 100 (0x64.) The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0x2D00 Units: dB Property 0x350A FM_BLEND_MULTIPATH_ATTACK_TIME The FM_BLEND_MULTIPATH_ATTACK_TIME property sets the transition time for which the stereo blend mitigation engine decreases the stereo separation based on Multipath. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 16 Units: ms FM_BLEND_MULTIPATH_STEREO_SEP 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 ST_SEPMAX[7:0] ST_SEPMIN[7:0] 0x2D 0x00 Bit Name Function 15:8 ST_SEPMAX[7:0] Sets the maxi mum stereo separation. Default is 45 dB. Range is 0–64 dB. 7:0 ST_SEPMIN[7:0] Sets the minimum stereo sepa ration. Default is 0 dB. Range is 0–64 dB. FM_BLEND_MULTIPATH_ATTACK_TIME 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 ATTACK[15:0] 0x0010 Bit Name Function 15:0 ATTACK[15:0] Sets the transition time for which the stereo blend mitigation engine decreases the stereo separation based on Multipath. Default is 16 ms. Range is 1–32767 ms.

118 Rev. 0.3 Property 0x350B FM_BLEND_MULTIPATH_RELEASE_TIME The FM_BLEND_MULTIPATH_RELEASE_TIME property sets the transiti on time for which the stereo blend mitigation engine increases the stereo separation based on RSSI. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 4000 Units: ms Property 0x3510 FM_BLEND_USN_THRESHOLDS The FM_BLEND_USN_THRESHOLDS property sets the USN thresholds for maximum and minimum stereo separation (set by Property 0x3511) on the blend engine. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0x341B Units: –dBFS FM_BLEND_MULTIPATH_RELEASE_TIME 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 RELEASE[15:0] 0x0FA0 Bit Name Function 15:0 RELEASE[15:0] Sets the transition time for which the stereo blend mitigation engine increases the stereo separation based on Multipath. Default is 4000 ms. Range is 1–32767 ms. FM_BLEND_USN_THRESHOLDS 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 USNMIN[7:0] USNMAX[7:0] 0x34 0x1B Bit Name Function 15:8 USNMIN[7:0] Sets the USN Min threshold. If USN is below this threshold, maximum ste- reo separation will be achieved as set by property 0x3511. Default is –52 dBFS. Range is 0–127 –dBFS. 7:0 USNMAX[7:0] Sets the USN Max threshold. If USN is above this threshold, minimum ste- reo separation will be achieved as set by property 0x3511. Default is –27 dBFS. Range is 0–127 –dBFS.

Rev. 0.3 119 Property 0x3511 FM_BLEND_USN_STEREO_SEP The FM_BLEND_USN_STEREO_SEP property sets the maximum and minimum stereo separation based on USN (set by Property 0x3510) on the blend engine. You can force a constant stereo separation value by setting ST_SEPMAX and ST_SEPMIN to the same value. To disable the stereo blend based on USN, set ST_SEPMAX = ST_SEPMIN = 100 (0x64.) The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0x2D00 Units: dB Property 0x3512 FM_BLEND_USN_ATTACK_TIME The FM_BLEND_USN_ATTACK_TIME property sets the tran sition time for which the stereo blend mitigation engine decreases the stereo separation based on USN. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 16 Units: ms FM_BLEND_USN_STEREO_SEP 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 ST_SEPMAX[7:0] ST_SEPMIN[7:0] 0x2D 0x00 Bit Name Function 15:8 ST_SEPMAX[7:0] Sets the maximum stereo sepa ration. Default is 45 dB. Range is 0–100 dB. 7:0 ST_SEPMIN[7:0] Sets the minimum stereo sepa ration. Default is 0 dB. Range is 0–100 dB. FM_BLEND_USN_ATTACK_TIME 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 ATTACK[15:0] 0x0010 Bit Name Function 15:0 ATTACK[15:0] Sets the transition time for which the stereo blend mitigation engine decreases the stereo separation based on USN. Default is 16 ms. Range is 1–32767 ms.

120 Rev. 0.3 Property 0x3513 FM_BLEND_USN_RELEASE_TIME The FM_BLEND_USN_RELEASE_TIME property sets the transition time for which the stereo blend mitigation engine increases the stereo separation based on USN. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 4000 Units: ms Property 0x3600 FM_HICUT_RSSI_THRESHOLDS The FM_Hi-cut_RSSI_THRESHOLDS property sets the RSSI thresholds for Hi-cut to begin band limiting and reach maximum band limiting on L+R channel based on max and min cutoff frequency (set by Property 0x3601) on the Hi-cut engine. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0x230F Units: dBµV FM_BLEND_USN_RELEASE_TIME 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 RELEASE[15:0] 0x0FA0 Bit Name Function 15:0 RELEASE[15:0] Sets the transition time for which the stereo blend mitigation engine increases the stereo separation based on USN. Default is 4000 ms. Range is 1–32767 ms. FM_HICUT_RSSI_THRESHOLDS 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 RSSIMAX[7:0] RSSIMIN[7:0] 0x23 0x0F Bit Name Function 15:8 RSSIMAX[7:0] Sets the RSSI level at which Hi-cut begins to band limit on the L+R channel based on cutoff frequency set by property 0x3601. Default is 35 dBµV. Range is –20–120 dBµV. 7:0 RSSIMIN[7:0] Sets the RSSI level at which Hi-cut reaches maximum band limiting on the L+R channel based on cutoff frequency set by property 0x3601. Default is 15 dBµV. Range is –20–120 dBµV.

Rev. 0.3 121 Property 0x3601 FM_HICUT_RSSI_CUTOFF_FREQ The FM_Hi-cut_RSSI_CUTOFF_FREQ property sets the maximum and minimum cutoff frequencies based on RSSI (set by Property 0x3600) on the Hi-cut engine. Y ou can force a constant cutoff frequency value by setting FREQ_MAX and FREQ_MIN to the same value. To disable the Hi-cut based on RSSI, set FREQ_MAX = FREQ_MIN = 180 (0xB4.) The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0xB428 Units: 100 Hz Property 0x3602 FM_HICUT_RSSI_ATTACK_TIME The FM_HI-CUT_RSSI_ATTACK_TIME property sets the tran sition time for which the Hi-cut mitigation engine lowers the cutoff frequency based on RSSI. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 16 Units: ms FM_HICUT_RSSI_CUTOFF_FREQ 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 FREQ_MAX[7:0] FREQ_MIN[7:0] 0xB4 0x28 Bit Name Function 15:8 FREQ_MAX[7:0] Sets the maximum cutoff frequency. Default is 18 kHz. Range is 0–18 kHz. 7:0 FREQ_MIN[7:0] Sets the minimum stereo sepa ration. Default is 4 kHz. Range is 0–18 kHz. FM_HICUT_RSSI_ATTACK_TIME 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 ATTACK[15:0] 0x0010 Bit Name Function 15:0 ATTACK[15:0] Sets the transition time for which the Hi-cut mitigation engine lowers the cutoff frequency based on RSSI. Default is 16 ms. Range is 1–32767 ms.

122 Rev. 0.3 Property 0x3603 FM_HICUT_RSSI_RELEASE_TIME The FM_HICUT_RSSI_RELEASE_TIME property sets the tran sition time for which the Hi-cut mitigation engine increases the cutoff frequency based on RSSI. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 4000 Units: ms Property 0x3608 FM_HICUT_MULTIPATH_THRESHOLDS The FM_HICUT_MULTIPATH_THRESHOLDS property sets th e Multipath thresholds fo r Hi-cut to begin band limiting and reach maximum band limiting on L+R channel based on max and min cutoff frequencies (set by Property 0x3609) on the Hi-cut engine. The CTS bit (and opti onal interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0x3250 FM_HICUT_RSSI_RELEASE_TIME 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 RELEASE[15:0] 0x0FA0 Bit Name Function 15:0 RELEASE[15:0] Sets the transition time for which the Hi-cut mitigation engine increases the cutoff frequency based on RSSI. Default is 4000 ms. Range is 1–32767 ms. FM_HICUT_MULTIPATH_THRESHOLDS 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 MULTMIN[7:0] MULTMAX[7:0] 0x32 0x50 Bit Name Function 15:8 MULTMIN[7:0] Sets the Multipath level at which Hi-cut reaches max band limiting on the L+R channel based on cutoff frequency set by property 0x3609. Default is 40. Range is 0–127%. 7:0 MULTMAX[7:0] Sets the Multipath level at which Hi-cut begins to band limit on the L+R channel based on cutoff frequency set by property 0x3609. Default is 80. Range is 0–127%.

Rev. 0.3 123 Property 0x3609 FM_HICUT_MULTIPATH_CUTOFF_FREQ The FM_HICUT_MULTIPATH_CUTOFF_FREQ property sets the maximum and minimum cutoff frequency based on Multipath (set by Property 0x3608) on the Hi-cut en gine. You can force a constant cutoff frequency value by setting FREQ_MAX and FREQ_MIN to the same value. To disable the Hi-cut based on Multipath, set FREQ_MAX = FREQ_MIN = 180 (0xB4.) The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0xB428 Units: 100 Hz Property 0x360A FM_HICUT_MULTIPATH_ATTACK_TIME The FM_HICUT_MULTIPATH_ATTACK_TIME property sets t he transition time for which the Hi-cut mitigation engine lowers the cutoff frequency based on Multipath. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 16 Units: ms FM_HICUT_MULTIPATH_CUTOFF_FREQ 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 FREQ_MAX[7:0] FREQ_MIN[7:0] 0xB4 0x28 Bit Name Function 15:8 FREQ_MAX[7:0] Sets the maximum cutoff frequency. Default is 18 kHz. Range is 0–18 kHz. 7:0 FREQ_MIN[7:0] Sets the minimum stereo sepa ration. Default is 4 kHz. Range is 0–18 kHz. FM_HICUT_MULTIPATH_ATTACK_TIME 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 ATTACK[15:0] 0x0010 Bit Name Function 15:0 ATTACK[15:0] Sets the transition time for which the Hi-cut mitigation engine decreases the cutoff frequency based on Multipath. Default is 16 ms. Range is 1–32767 ms.

124 Rev. 0.3 Property 0x360B FM_HICUT_MULTIPATH_RELEASE_TIME The FM_HICUT_MULTIPATH_RELEASE_TIME property sets the transi tion time for which the Hi-cut mitigation engine increases the cutoff frequency based on RSSI. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 4000 Units: ms Property 0x3610 FM_HICUT_USN_THRESHOLDS The FM_HICUT_USN_THRESHOLDS property sets the USN thresholds for Hi-cut to begin band limiting and reach maximum band limiting on L+R channel based on max and min cutoff frequencies (set by Property 0x3611) on the Hi-cut engine. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0x250F Units: –dBFS FM_HICUT_MULTIPATH_RELEASE_TIME 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 RELEASE[15:0] 0x0FA0 Bit Name Function 15:0 RELEASE[15:0] Sets the transition time for which the Hi-cut mitigation engine increases the cutoff frequency based on Multipath. Default is 4000 ms. Range is 1–32767 ms. FM_HICUT_USN_THRESHOLDS 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 USNMIN[7:0] USNMAX[7:0] 0x25 0x0F Bit Name Function 15:8 USNMIN[7:0] Sets the USN level at which Hi-cut reaches max band limiting on the L+R channel based on cutoff frequency set by property 0x3611. Default is –37 dBFS. Range is 0–127 –dBFS. 7:0 USNMAX[7:0] Sets the Multipath level at which Hi-cut begins to band limit on the L+R channel based on cutoff frequency set by property 0x3611. Default is –15 dBFS. Range is 0–127 –dBFS.

Rev. 0.3 125 Property 0x3611 FM_HICUT_USN_CUTOFF_FREQ The FM_HICUT_USN_CUTOFF_FREQ property sets the maximum and minimum cutoff frequency based on USN (set by Property 0x3610) on the Hi-cut engine. You can force a constant cutoff frequency value by setting FREQ_MAX and FREQ_MIN to the same value. To disable the Hi-cut based on USN, set FREQ_MAX = FREQ_MIN = 180 (0xB4.) The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0xB428 Units: 100 Hz Property 0x3612 FM_HICUT_USN_ATTACK_TIME The FM_HICUT_USN_ATTACK_TIME property sets the transi tion time for which the Hi-cut mitigation engine lowers the cutoff frequency based on USN. The CTS bit (and optional interrupt) is set wh en it is safe to send the next command. This property may only be set or read in powerup mode. Default: 16 Units: ms FM_HICUT_USN_CUTOFF_FREQ 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 FREQ_MAX[7:0] FREQ_MIN[7:0] 0xB4 0x28 Bit Name Function 15:8 FREQ_MAX[7:0] Sets the maximum cutoff frequency. Default is 18 kHz. Range is 0–18 kHz. 7:0 FREQ_MIN[7:0] Sets the minimum stereo sepa ration. Default is 4 kHz. Range is 0–18 kHz. FM_HICUT_USN_ATTACK_TIME 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 ATTACK[15:0] 0x0010 Bit Name Function 15:0 ATTACK[15:0] Sets the transition time for which the Hi-cut mitigation engine lowers the cutoff frequency based on USN. Default is 16 ms. Range is 1–32767 ms.

126 Rev. 0.3 Property 0x3613 FM_HICUT_USN_RELEASE_TIME The FM_HICUT_USN_RELEASE_TIME property sets the transition time for which the Hi-cut mitigation engine increases the cutoff frequency based on USN. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 4000 Units: ms Property 0x3700 FM_HIBLEND_RSSI_THRESHOLDS The FM_HIBLEND_RSSI_THRESHOLDS property sets the R SSI thresholds for Hi-blend to begin band limiting and reach maximum band limiting on L-R channel based on max and min cutoff frequency (set by Property 0x3701) on the Hi-blend engine. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0x371B Units: dBµV FM_HICUT_USN_RELEASE_TIME 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 RELEASE[15:0] 0x0FA0 Bit Name Function 15:0 RELEASE[15:0] Sets the transition time for which the Hi-cut mitigation engine increases the cutoff frequency based on USN. Default is 4000 ms. Range is 1–32767 ms. FM_HIBLEND_RSSI_THRESHOLDS 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 RSSIMAX[7:0] RSSIMIN[7:0] 0x37 0x1B Bit Name Function 15:8 RSSIMAX[7:0] Sets the RSSI level at which Hi-blend begins to band limit on the L-R chan- nel based on cutoff frequency set by property 0x3701. Default is 55 dBµV. Range is –20 to 120 dBµV. 7:0 RSSIMIN[7:0] Sets the RSSI level at which Hi-blend reaches maximum band limiting on the L-R channel based on cutoff frequency set by property 0x3701. Default is 27 dBµV. Range is –20 to 120 dBµV.

Rev. 0.3 127 Property 0x3701 FM_HIBLEND_RSSI_CUTOFF_FREQ The FM_HIBLEND_RSSI_CUTOFF_FREQ property sets the maximum and minimum cutoff frequencies based on RSSI (set by Property 0x3700) on the Hi-blend engine. You can force a constant cutoff frequency value by setting FREQ_MAX and FREQ_MIN to the same value. To disable the Hi-blend based on RSSI, set FREQ_MAX = FREQ_MIN = 180 (0xB4.) The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0xB41E Units: 100 Hz Property 0x3702 FM_HIBLEND_RSSI_ATTACK_TIME The FM_HIBLEND_RSSI_ATTACK_TIME property sets the transition time for which the Hi-blend mitigation engine lowers the cutoff frequency based on RSSI. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 4 Units: ms FM_HIBLEND_RSSI_CUTOFF_FREQ 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 FREQ_MAX[7:0] FREQ_MIN[7:0] 0xB4 0x1E Bit Name Function 15:8 FREQ_MAX[7:0] Sets the maximum cutoff frequency. Default is 18 kHz. Range is 0–18 kHz. 7:0 FREQ_MIN[7:0] Sets the minimum stereo sepa ration. Default is 3 kHz. Range is 0–18 kHz. FM_HIBLEND_RSSI_ATTACK_TIME 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 ATTACK[15:0] 0x0004 Bit Name Function 15:0 ATTACK[15:0] Sets the transition time for which the Hi-blend mitigation engine lowers the cutoff frequency based on RSSI. Default is 4 ms. Range is 1–32767 ms.

128 Rev. 0.3 Property 0x3703 FM_HIBLEND_RSSI_RELEASE_TIME The FM_HIBLEND_RSSI_RELEASE_TIME pr operty sets the transition time for which the Hi-blend mitigation engine increases the cutoff frequency based on RSSI. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 8000 Units: ms Property 0x3708 FM_HIBLEND_MULTIPATH_THRESHOLDS The FM_HIBLEND_MULTIPATH_THRESHOLDS property sets the Multipath thresholds for Hi-blend to begin band limiting and reach maximum band limiting on L-R channel based on max and min cutoff frequencies (set by Property 0x3709) on the Hi-blend engine. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0x193C FM_HIBLEND_RSSI_RELEASE_TIME 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 RELEASE[15:0] 0x1F40 Bit Name Function 15:0 RELEASE[15:0] Sets the transition time for which the Hi-blend mitigation engine increases the cutoff frequency based on RSSI. Default is 8000 ms. Range is 1–32767 ms. FM_HIBLEND_MULTIPATH_THRESHOLDS 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 MULTMIN[7:0] MULTMAX[7:0] 0x19 0x3C Bit Name Function 15:8 MULTMIN[7:0] Sets the Multipath level at which Hi-cut reaches max band limiting on the L- R channel based on cutoff frequency set by property 0x3709. Default is 25. Range is 0–127%. 7:0 MULTMAX[7:0] Sets the Multipath level at which Hi-blend begins to band limit on the L-R channel based on cutoff frequency set by property 0x3709. Default is 60. Range is 0–127%.

Rev. 0.3 129 Property 0x3709 FM_HIBLEND_MULTIPATH_CUTOFF_FREQ The FM_HIBLEND_MULTIPATH_CUTOFF_FREQ property sets the maximum and minimum cutoff frequency based on Multipath (set by Property 0x3708) on the Hi-b lend engine. You can force a constant cutoff frequency value by setting FREQ_MAX and FREQ_MIN to the same va lue. To disable the Hi-blend based on Multipath, set FREQ_MAX = FREQ_MIN = 180 (0xB4.) The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0xB41E Units: 100 Hz Property 0x370A FM_HIBLEND_MULTIPATH_ATTACK_TIME The FM_HIBLEND_MULTIPATH_ATTACK_TIME property sets the transition time for which the Hi-blend mitigation engine lowers the cutoff frequency based on Multipath. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 4 Units: ms FM_HIBLEND_MULTIPATH_CUTOFF_FREQ 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 FREQ_MAX[7:0] FREQ_MIN[7:0] 0xB4 0x1E Bit Name Function 15:8 FREQ_MAX[7:0] Sets the maximum cutoff frequency. Default is 18 kHz. Range is 0–18 kHz. 7:0 FREQ_MIN[7:0] Sets the minimum stereo sepa ration. Default is 3 kHz. Range is 0–18 kHz. FM_HIBLEND_MULTIPATH_ATTACK_TIME 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 ATTACK[15:0] 0x0004 Bit Name Function 15:0 ATTACK[15:0] Sets the transition time for which the Hi-blend mitigation engine decreases the cutoff frequency based on Multipath. Default is 4 ms. Range is 1–32767 ms.

130 Rev. 0.3 Property 0x370B FM_HIBLEND_MULTIPATH_RELEASE_TIME The FM_HIBLEND_MULTIPATH_RELEASE_TIME property se ts the transition time for which the Hi-blend mitigation engine increases the cutoff frequency based on RSSI. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 8000 Units: ms Property 0x3710 FM_HIBLEND_USN_THRESHOLDS The FM_HIBLEND_USN_THRESHOLDS property sets the USN thresholds for Hi-blend to begin band limiting and reach maximum band limiting on L-R channel based on max and min cutoff frequencies (set by Property 0x3711) on the Hi-blend engine. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0x371E Units: –dBFS FM_HIBLEND_MULTIPATH_RELEASE_TIME 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 RELEASE[15:0] 0x1F40 Bit Name Function 15:0 RELEASE[15:0] Sets the transition time for which the Hi-blend mitigation engine increases the cutoff frequency based on Multipath. Default is 8000 ms. Range is 1–32767 ms. FM_HIBLEND_USN_THRESHOLDS 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 USNMIN[7:0] USNMAX[7:0] 0x37 0x1E Bit Name Function 15:8 USNMIN[7:0] Sets the USN level at which Hi-blend reaches max band limiting on the L-R channel based on cutoff frequency set by property 0x3711. Default is –55 dBFS. Range is 0–127 –dBFS. 7:0 USNMAX[7:0] Sets the Multipath level at which Hi-blend begins to band limit on the L-R channel based on cutoff frequency set by property 0x3711. Default is –30 dBFS. Range is 0–127 –dBFS.

Rev. 0.3 131 Property 0x3711 FM_HIBLEND_USN_CUTOFF_FREQ The FM_HIBLEND_USN_CUTOFF_FREQ property sets the maximum and minimum cutoff frequency based on USN (set by Property 0x3710) on the Hi-blend engine. You can force a constant cutoff frequency value by setting FREQ_MAX and FREQ_MIN to the same value. To disable the Hi-blend based on USN, set FREQ_MAX = FREQ_MIN = 180 (0xB4.) The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0xB41E Units: 100 Hz Property 0x3712 FM_HIBLEND_USN_ATTACK_TIME The FM_HIBLEND_USN_ATTACK_TIME property sets the transition time for which the Hi-blend mitigation engine lowers the cutoff frequency based on USN. The CTS bit (and optional interrupt) is set wh en it is safe to send the next command. This property may only be set or read in powerup mode. Default: 4 Units: ms FM_HIBLEND_USN_CUTOFF_FREQ 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 FREQ_MAX[7:0] FREQ_MIN[7:0] 0xB4 0x1E Bit Name Function 15:8 FREQ_MAX[7:0] Sets the maximum cutoff frequency. Default is 18 kHz. Range is 0–18 kHz. 7:0 FREQ_MIN[7:0] Sets the minimum stereo sepa ration. Default is 3 kHz. Range is 0–18 kHz. FM_HIBLEND_USN_ATTACK_TIME 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 ATTACK[15:0] 0x0004 Bit Name Function 15:0 ATTACK[15:0] Sets the transition time for which the Hi-blend mitigation engine lowers the cutoff frequency based on USN. Default is 4 ms. Range is 1–32767 ms.

132 Rev. 0.3 Property 0x3713 FM_HIBLEND_USN_RELEASE_TIME The FM_HIBLEND_USN_RELEASE_TI ME property sets the tr ansition time for which the Hi-blend mitigation engine increases the cutoff frequency based on USN. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 8000 Units: ms FM_HIBLEND_USN_RELEASE_TIME 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 RELEASE[15:0] 0x1F40 Bit Name Function 15:0 RELEASE[15:0] Sets the transition time for which the Hi-blend mitigation engine increases the cutoff frequency based on USN. Default is 8000 ms. Range is 1–32767 ms.

Rev. 0.3 133 Property 0x4000 FM_RDS_INTERRUPT_SOURCE The FM_RDS_INTERRUPT_SOURCE property configures interrupt related to RDS. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. FM_RDS_INTERRUPT_SOURCE 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 0x000 RDSTPPTY RDSPI 0 RDSSYNC RDSRECV 0x000 0 0 0 0 0 Bit Name Function 15:5 Reserved Always write 0.

4 RDSTPPTY

If set, generates RDS Interrupt when first valid Block B data has been received or if Block B data is different from last valid Block B data. 0 = Disabled. 1 = Enabled.

3 RDSPI

If set, generates RDS Interrupt when first valid Block A data has been received or if Block A data is different from last valid Block A data. 0 = Disabled. 1 = Enabled. 2 Reserved Always write 0.

1 RDSSYNC

If set, generates RDS interrupt when RDS Synchronization status changes. Default is 0. 0 = Disabled. 1 = Enabled.

0 RDSRECV

If set, generate an interrupt whenever the RDS FIFO has at least FM_RDS_INTERRUPT_FIFO_COUNT entries. Default is 0 0 = Disabled. 1 = Enabled.

134 Rev. 0.3 Property 0x4001 FM_RDS_INTERRUPT_FIFO_COUNT The FM_RDS_INTERRUPT_FIFO_COUNT property sets the minimum number of RDS groups stored in the RDS FIFO before RDSRECV is set. RDSRECV is disabled if set to 0. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0 FM_RDS_INTERRUPT_FIFO_COUNT 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 0x00 DEPTH[7:0] 0x00 0x00 Bit Name Function 15:8 Reserved Always write 0. 7:0 DEPTH[7:0] Sets the minimum number of RDS Groups stored in the RDS FIFO required before RDSRECV is set. RDSRECV is disabled if set to 0. Default is 0. Range is 0–25

Rev. 0.3 135 Property 0x4002 FM_RDS_CONFIG The FM_RDS_CONFIG property configures RDS settings to enable RDS processing (RDSEN) and set RDS block error thresholds. When a RDS Group is received, all block errors must be less than or equal to the associated block error threshold for the group to be stored in the RDS FIFO. If blocks with errors are permitted into the FIFO, the block error information can be reviewed when the group is read using the FM_RDS_STATUS command. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0x0000 FM_RDS_CONFIG 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 0x00 BLETHB[1:0] BLETHCD[1:0] 0x0 RDSEN 0x00 0x0 0x0 0x0 0 Bit Name Function 15:8 Reserved Always write 0. 7:6 BLETHB[1:0] Block Error Threshold BLOCKB. Block B is most critical because it tells what C and D contain. 0 = No errors. 1 = 1–2 bit errors detected and corrected. 2 = 3–5 bit errors detected and corrected. 3 = Uncorrectable. 5:4 BLETHCD[1:0] Block Error Threshold for BLOCKC and BLOCKD. 0 = No errors. 1 = 1–2 bit errors detected and corrected. 2 = 3–5 bit errors detected and corrected. 3 = Uncorrectable. 3:1 Reserved Always write 0.

0 RDSEN

Enables RDS processing. Default is 0. 0 = RDS Disabled. 1 = RDS Enabled.

136 Rev. 0.3 Property 0x4003 FM_RDS_CONFIDENCE The FM_RDS_CONFIDENCE property sets the required re ceiver confidence level for each RDS block prior to demodulation. A higher confi dence requirement will result in more blo ck errors (higher perc entage of blocks with BLE=3), but reduces the chance of decoder errors (lower percentage of blocks that contain incorrect information despite having BLE<3). Higher confidence requirements may result in a decrease in the frequency with which RDS data is stored in the FIFO. Higher bl ock error rates will affect RDS sensitiv ity tests. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read when in the powerup mode. Default: 0x1111 FM_RDS_CONFIDENCE 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 CONFIDENCEA[3:0] CONFIDENCEB[3:0] CONFIDENCEC[3:0] CONFIDENCED[3:0] 0x1 0x1 0x1 0x1 Bit Name Function 15:12 CONFIDENCEA[3:0] Sets the decoder error rate threshold for BLOCK A. 0=R e s e r v e d . 1 = Lowest confidence required. A valid and usable confidence threshold. 2–14 = Medium confidence required. High value may result in all blocks being marked as uncorrectable. 15 = Highest confidence required. This setting may result in all blocks being marked as uncorrectable. 11:8 CONFIDENCEB[3:0] Sets the decoder error rate threshold for BLOCK B. 0=R e s e r v e d . 1 = Lowest confidence required. A valid and usable confidence threshold. 2–14 = Medium confidence required. High value may result in all blocks being marked as uncorrectable. 15 = Highest confidence required. This setting may result in all blocks being marked as uncorrectable. 7:4 CONFIDENCEC[3:0] Sets the decoder error rate threshold for BLOCK C. 0=R e s e r v e d . 1 = Lowest confidence required. A valid and usable confidence threshold. 2–14 = Medium confidence required. High value may result in all blocks being marked as uncorrectable. 15 = Highest confidence required. This setting may result in all blocks being marked as uncorrectable. 3:0 CONFIDENCED[3:0] Sets the decoder error rate threshold for BLOCK D. 0=R e s e r v e d . 1 = Lowest confidence required. A valid and usable confidence threshold. 2–14 = Medium confidence required. High value may result in all blocks being marked as uncorrectable. 15 = Highest confidence required. This setting may result in all blocks being marked as uncorrectable.

Table 16. AM Receiver Command Summary 0x40 AM_TUNE_FREQ Tunes the AM receiver to a frequency in 1 kHz steps. 0x41 AM_SEEK_START Initiates a seek for a channel that meets the validation criteria for AM. 0x42 AM_RSQ_STATUS Returns status information about the received signal quality. 0x45 AM_ACF_STATUS Returns status informatio n about automatically controlled features. 0x47 AM_AGC_STATUS Reports the status of AM AGC. Table 17. AM Receiver Property Summary Sets the maximum soft mute attenuation. Sets the SNR threshold for soft mute to start.

Enables the ACF interrupt sources. Sets the softmute interrupt threshold in dB. Table 17. AM Receiver Property Summary (Continued)

Sets the minimum LowCut cutoff frequency. Sets the maximum LowCut cutoff frequency.

Rev. 0.3 141 9.3.1. AM Receiver Commands Command 0x40 AM_TUNE_FREQ The AM_TUNE_FREQ command sets the AM Receiver to tune to a frequency in 1 kHz units. The CTS bit (and optional interrupt) is set when it is safe to send the next command. The ERR bit (and optional interrupt) is set if an invalid argument is sent. Note that only a single interrupt occurs if both the CTS and ERR bits are set. The optional STC interrupt is set when the command completes. This command may only be sent in powerup mode. The command clears the STC bit if it is already set. Command B i t 7 6 5 4 321 0 CMD 0x40 ARG1 0 ZIFSR 0 ARG2 FREQH[7:0] ARG3 FREQL[7:0] ARG4 ANTCAPH[7:0] ARG5 ANTCAPL[7:0]

142 Rev. 0.3 Response ARG Bit Name Function 1 7 Reserved Always write 0. 1 6 ZIFSR Sets the ZIP sample rate. ZIFSR=0, low ZIF sample rate (40.625, 42.1875, or 46.5117 kHz, depending on crys- tal frequency) ZIFSR=1, high ZIF sample rate (650, 675, or 744.1875 kHz, depending on crystal fre- quency) See section “7. Digital ZIF I/Q Interface”. 1 5:0 Reserved Always write 0. 27 : 0 F R E Q H[7:0] Tune Frequency High Byte. This byte in combination with FREQL selects the tune frequency in units of 1 kHz. Valid range is from 520 to 1710 (520–1710 kHz). 37 : 0 F R E Q L[7:0] Tune Frequency Low Byte. This byte in combination with FREQH selects the tune frequency in units of 1 kHz. Valid range is from 520 to 1710 (520–1710 kHz). 47 : 0 A N T C A P H[7:0] Antenna Tuning Capacitor High Byte. This byte, in combination with ANTCAPL[7:0], sets the antenna tuning capacitor value in 92 fF increments. Max value is 580 pF. Range is 1-6304. Setting ANTCAP to 0 automatically determines the capacitor value. 57 : 0 A N T C A P L[7:0] Antenna Tuning Capacitor Low Byte. This byte, in combination with ANTCAPH[7:0], sets the antenna tuning capacitor value in 92 fF increments. Max value is 580 pF. Range is 1-6304. Setting ANTCAP to 0 automatically determines the capacitor value. B i t 76543210 STATUS CTS ERR XX RSQINT X ACFINT STCINT

Rev. 0.3 143 Command 0x41 AM_SEEK_START The AM_SEEK_START command begins searching for a valid frequency. In order for a station to be considered valid, each of the following thresholds must be met: AM_VALID_SNR_THRESHOLD, AM_VALID_RSSI_THRESHOLD, and AM_VALID_MAX_TUNE_ERROR. Clears any pending STCINT or RSQINT interrupt status. Seek can be cancelled through setti ng the CANCEL bit in the AM_RSQ_STATUS command. The CTS bit (and optional interrupt) is set when it is safe to send the next command. RSQINT status is only cleared by the AM_RSQ_STATUS command when the RSQACK bit is set. The ERR bit (and optional interrupt) is set if an invalid argument is sent. Note that only a single interrupt occurs if both the CTS and ERR bits are set. The optional STC interrupt is set when the command completes. This command may only be sent in powerup mode. The command clears the STCINT bit if it is already set. Command Response B i t 76543210 CMD 0x41 ARG1 0000 SEEKUP WRAP 00 ARG Bit Name Function 1 7:4 Reserved Always write 0.

13 W R A P

Wrap/Halt. Determines whether the seek should Wrap = 1, or Halt = 0 when it hits the band limit. 1 2 SEEKUP Seek Up/Down. Determines the direction of the search, either UP = 1, or DOWN = 0. 1 1:0 Reserved Always write 0. B i t 76543210 STATUS CTS ERR XX RSQINT X ACFINT STCINT

144 Rev. 0.3 Command 0x42 AM_RSQ_STATUS The AM_RSQ_STATUS command returns status information about the received signal quality. This command returns Received Signal Strength In dicator (RSSI), Signal to Noise Ratio (SNR), High Side Adjacent Channel Strength (HASSI), Low Side Adjace nt Channel Strength (L ASSI), Frequency Offs et (FREQOFF), and AM Modulation Index (MOD) associated with the desired channel. It also indicates valid channel (VALID) and AFC rail status (AFCRL). This command can be used to check if th e received signal is above the RSSI high threshold as reported by RSSIHINT, or below the RSSI low threshold as reported by RSSILINT. It can also be used to check if the signal is above the SNR high threshold as reported by SNRHINT, or below the SNR low threshold as reported by SNRLINT. The command clears the RSQINT, SNRHINT, SNRLINT, RSSIHINT and RSSILINT interrupt bits when RSQACK bit of ARG1 is set. If the condition is still true after the interrupt is cleared another interrupt will fire assuming that bit is enabled in AM_RSQ_INTERRUPT_SOURCE. The CTS bit (and op tional interrupt) is set when it is safe to send the next command. This command may only be sent in powerup mode. Command B i t 76543210 CMD 0x42 ARG1 0000 RSQACK ATTUNE CANCEL STCACK ARG Bit Name Function 1 7:4 Reserved Always write 0. 1 3 RSQACK Clears RSQINT, SNRHINT, SNRLINT, RSSIHINT, RSSILINT if set. 1 2 ATTUNE Returns the values of metrics as of tune time. When the AT_TUNE bit is set, values returned for RSQ_STATUS are the values calculated at tune and do not change unless another TUNE_FREQ command is called. This feature can be used to determine why seek stopped at the current station. 1 1 CANCEL Aborts a seek or tune currently in progress 0 = Don't abort. 1=A b o r t . 1 0 STCACK Clears the STC interr upt status indicator if set.

Rev. 0.3 145 Response B i t 76543210 STATUS CTS ERR XX RSQINT X ACFINT STCINT RESP1 X X X X SNRHINT SNRLIN T RSSIHINT RSSILINT RESP 2 BLTF X SNR- READY RSSIREA DY X X AFCRL VALID RESP 3 READFREQ[15:8] RESP 4 READFREQ[7:0] RESP 5 FREQOFF[7:0] RESP 6 RSSI[7:0] RESP 7 SNR[7:0] RESP 8 XXXXXXXX RESP 9 LASSI[7:0] RESP 10 HASSI[7:0] RESP 11 XXXXXXXX RESP 12 MOD[7:0] RESP 13 ANTCAPH[7:0] RESP 14 ANTCAPL[7:0]

146 Rev. 0.3 RESP Bit Name Function 17 : 4 Reserved Values may vary. SNRHINT SNR Detect High 0 = Received SNR has not exceeded above SNR programmed using AM_RSQ_SNR_HIGH_THRESHOLD. 1 = Received SNR has exceeded above SNR threshold programmed using AM_RSQ_SNR_HIGH_THRESHOLD. SNRLINT SNR Detect Low 0 = Received SNR has not fallen below SNR threshold programmed using AM_RSQ_SNR_LOW_THRESHOLD. 1 = Received SNR has fallen below SNR threshold programmed using AM_RSQ_SNR_LOW_THRESHOLD. RSSIHINT RSSI Detect High 0 = RSSI has not exceeded above RSSI threshold programmed using AM_RSQ_RSSI_HIGH_THRESHOLD. 1 = RSSI has exceeded above RSSI threshold programmed using AM_RSQ_RSSI_HIGH_THRESHOLD. RSSILINT RSSI Detect Low 0 = RSSI has not fallen below RSSI threshold. programmed using AM_RSQ_RSSI_LOW_THRESHOLD. 1 = RSSI has fallen below RSSI threshold programmed using AM_RSQ_RSSI_LOW_THRESHOLD.

27 B L T F

Reports if a seek hit the band limit (WRAP = 0 in AM_- SEEK_START) or wrapped to the original frequency (WRAP = 1). 2 6 Reserved Values may vary.

Rev. 0.3 147 2 5 SNRREADY SNR Status When set, indicates that the SNR metric was read as part of a tune. If this flag is not set once tune completes, the SNR metric was not measured. A metric not mea- sured indicates that a tune was terminated prematurely due to an invalidating condition (i.e., RSSI did not meet the minimum threshold).In this case, tune time RSQ will report 0 for SNR. The normal running SNR is not affected by this flag. 0 = SNR measurement in progress (tune in progress). 1 = SNR measurement ready or not taken (tune com- pleted). 2 4 RSSIREADY RSSI Status When set, indicates that the RSSI metric was read as part of a tune. If this flag is not set once tune completes, the RSSI metric was not measured. A metric not mea- sured indicates that a tune was terminated prematurely due to an invalidating condition (i.e., RSSI did not meet the minimum threshold).In this case, tune time RSQ will report 0 for RSSI. The normal running RSSI is not affected by this flag. 0 = RSSI measurement in progress (tune in progress). 1 = RSSI measurement ready or not taken (tune com- pleted). 2 3:2 Reserved Values may vary 2 1 AFCRL Set if the AFC rails (AFC gets railed if FREQOFF > MAX_TUNE_ERROR).

20 V A L I D

Reports if the channel is valid based on the settings of AM_VALID_RSSI_THRESHOLD, AM_VALID_SNR_- THRESHOLD, AM_VALID_MAX_TUNE_ERROR. 3,4 15:0 READFREQ[15:0] Returns the currently tuned frequency. 5 7:0 FREQOFF[7:0] Frequency offset in units of 2 ppm (–128 to 127). 6 7:0 RSSI[7:0] Received Signal Strength indicator in dBµV (–128 to 127). 7 7:0 SNR[7:0] RF SNR indicator in dB (–128 to 127). 8 7:0 Reserved Values may vary 9 7:0 LASSI[7:0] Low Side Adjacent Channel Strength Indicator reports the Signal + Noise power relative to the carrier. (–128 to 127). 10 7:0 HASSI[7:0] High Side Adjacent Channel Strength Indicator reports the Signal + Noise power relative to the carrier. (–128 to 127). 11 7:0 Reserved Values may vary. 12 7:0 MOD[7:0] AM Modulation Index in percent range 0–100. RESP Bit Name Function

148 Rev. 0.3 13 7:0 ANTCAP H[7:0] Antenna Tuning Capacitor High Byte. This byte, in combination with ANTCAPL[7:0], reports the antenna tuning capacitor value in 92 fF increments. Max value is 580 pF. Range is 1-6304. 14 7:0 ANTCAP L[7:0] Antenna Tuning Capacitor High Byte. This byte, in combination with ANTCAPH[7:0], reports the antenna tuning capacitor value in 92 fF increments. Max value is 580 pF. Range is 1-6304. RESP Bit Name Function

Rev. 0.3 149 Command 0x45 AM_ACF_STATUS The AM_ACF_STATUS command returns status information about automatically controlled features. This command returns the Soft Mute Attenuation, Channel Filter Bandwidth, and Hi-cut cutoff frequency associated with the desired channel. If SMUTE bit is high it indicates that is audio is soft muted. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This command may only be sent in powerup mode. Command Response B i t 76543210 CMD 0x45 ARG1 0 ACFACK ARG Bit Name Function 1 7:1 Reserved Always write 0. 1 0 ACFACK If set to 1, clears ACFINT and any ACF interrupt bits. B i t 7654 3 2 1 0 STATUS CTS ERR XX RSQINT X ACFINT STCINT RESP1 XXX XXXX HICUT_INT CHBW_INT SOFTMUTE_INT RESP2 XXXXXXX SMUTE RESP3 XXX SMATTN[4:0] RESP4 CHANBW[7:0] RESP5 HICUT [7:0]

150 Rev. 0.3 RESP Bit Name Function 1 7:3 Reserved Values may vary.

12 H I C U T _ I N T Indicates that Hi-cut cutoff frequency has crossed below the

Hi-cut threshold set by AM_ACF_HICUT_THRESHOLD. 1 1 CHBW_INT Indicates that channel filter bandwidth is less than the thresh- old set by ACF_CHBW_THRESHOLD. 1 0 SOFTMUTE_INT Indicates that SM attenuation has increased above ACF_SM_THRESHOLD. 2 7:1 Reserved Values may vary. 20 S M U T E 0 = Audio is not soft muted. 1 = Audio is soft muted. 3 7:5 Reserved Values may vary. 3 4:0 SMATTN[4:0] Soft mute attenuation level in dB. Range: 0–31. 4 7:0 CHANBW[7:0] Channel filter bandwidth in 100 Hz. Range: 0–150. 5 7:0 HICUT [7:0] Hi-cut cutoff frequency in units of 100 Hz. Range: 10–50.

Rev. 0.3 151 Command 0x47 AM_AGC_STATUS The AM_AGC_STATUS command reports the current status of the AM AGC. The command is complete when the CTS bit (and optional interrupt) is set. This command may only be sent in powerup mode. Command Response B i t 76543210 CMD 0x47 B i t 76543210 Status CTS ERR XX RSQINT X ACFINT STCINT RESP1 XXXXXX AMHI AMLO RESP 2 XX RESP 3 XX RESP 4 PGAGAIN[7:0] RESP 5 RFATTN[7:0] RESP Bit Name Function 1 7:2 Reserved Values may vary. 11 A M H I 0 = AM LNA PD high threshold is not tripped. 1 = AM LNA PD high threshold is tripped. 10 A M L O 0 = AM LNA PD low threshold is not tripped. 1 = AM LNA PD low threshold is tripped. 2 7:0 Reserved Values may vary. 3 7:0 Reserved Values may vary. 4 7:0 PGAGAIN[7:0] PGA gain in dB. 5 7:0 RFATTN[7:0] AM loop resistive attenuation index. Range: 0-63 0 = 800 Kohms ~ no attenuation 1 = 0.875 * 800 k 2 = 0.875^2 * 800 k 63 = 0.875^63 * 800 k = 177 

152 Rev. 0.3 9.3.2. AM Receiver Properties Property 0x0400 AM_SOFT_MUTE_MAX_ATTENUATION The AM_SOFT_MUTE_MAX_ATTENUATION property sets the maximum attenuation in dB that will be applied by the softmute feature. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 12 Units: dB Property 0x0401 AM_SOFT_MUTE_TRIGGER_THRESHOLD The AM_SOFT_MUTE_TRIGGER_THRESHOLD property sets the SNR threshold in dB to engage softmute. The CTS bit (and optional interrupt) is set when it is sa fe to send the next command. If USE_RSSI is set in AM_ACF_CONTROL_SOURCE property, then property 0x0401 refers to RSSI threshold. This property may only be set or read in powerup mode. Default: 8 Units: dB AM_SOFT_MUTE_MAX_ATTENUATION 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 0x000 SMATTN[4:0] 0x000 0x0C Bit Name Function 15:5 Reserved Always write 0. 4:0 SMATTN[4:0] Sets the maximum attenuation in dB that will be applied by the softmute feature. Default is 12 dB. Range is 0–31 dB. AM_SOFT_MUTE_TRIGGER_THRESHOLD 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 0x00 SMTRGTH[7:0] 0x00 0x08 Bit Name Function 15:8 Reserved Always write 0. 7:0 SMTRGTH[7:0] Sets the SNR threshold in dB to engage softmute. Default is 8 dB. Range is –127 to 127 dB.

Rev. 0.3 153 Property 0x0402 AM_SOFT_MUTE_END_THRESHOLD The AM_SOFT_MUTE_END_THRESHOLD property sets the SNR threshold in dB at which softmute attenuation will be set to its maximum va lue. When the SNR is at this level or lo wer, the audio attenuation will be set to AM_SOFT_MUTE_MAX_ATTENUATION. The CTS bit (and optional interrupt) is set when it is safe to send the next command. If USE_RSSI is set in AM_ACF_CONTROL_SOURCE property, then property 0x0402 refers to RSSI threshold. This property may only be set or read in powerup mode. Default: 0 Units: dB Property 0x0403 AM_SOFT_MUTE_RELEASE_TIME The AM_SOFT_MUTE_RELEASE_TIME property sets the maximum time in ms it takes to unmute the audio. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 500 Units: ms AM_SOFT_MUTE_END_THRESHOLD 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 0x00 SMENDTH[7:0] 0x00 0x00 Bit Name Function 15:8 Reserved Always write 0. 7:0 SMENDTH[7:0] Sets the SNR threshold in dB at which softmute attenuation will be set to its maximum value given by AM_SOFT_MUTE_MAX_ATTENUATION property. Default is 0 dB. Range is –127 to 127 dB. AM_SOFT_MUTE_RELEASE_TIME 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 RELEASE[15:0] 0x01F4 Bit Name Function 15:0 RELEASE[15:0] Sets the maximum time in ms it takes to unmute the audio. Default is 500 ms. Range is 1–32767 ms. Note that there will be 16 ms of filter delay for the RSSI/SNR metric before softmute can engage/disen- gage.

154 Rev. 0.3 Property 0x0404 AM_SOFT_MUTE_ATTACK_TIME The AM_SOFT_MUTE_ATTACK_TIME property sets the maximum time in ms it takes to mute the audio. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 120 Units: ms Property 0x0500 AVC_MIN_GAIN The AVC_MIN_GAIN property sets the minimum gain for automatic volume control. The minimum gain value is given by MINGAIN = g * 170 where g is the desired minimum AVC gain in dB. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: –2048 AM_SOFT_MUTE_ATTACK_TIME 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 ATTACK[15:0] 0x0078 Bit Name Function 15:0 ATTACK[15:0] Sets the maximum time in ms it takes to mute the audio. Default is 120 ms. Range is 1–32767 ms. Note that there will be 16 ms of filter delay for the RSSI/SNR metric before softmute can engage/ disengage. AVC_MIN_GAIN 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 MINGAIN[15:0] 0xF800 Bit Name Function 15:0 MINGAIN[15:0] The minimum gain value for the AVC. MINGAIN = g x 170. Range for MIN- GAIN is –4096 to 3061. This implies that the range of g is –24 dB to +18 dB

Rev. 0.3 155 Property 0x0501 AVC_MAX_GAIN The AVC_MAX_GAIN property sets the maximum gain fo r automatic volume control. The maximum gain value is given by MAXGAIN = g x 170 where g is the desired maximum AVC gain in dB. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 10220 Property 0x0700 AM_FE_AGC_CONFIG Specifies the input path for the RF signal and other front -end configuration options. The CTS bit (and optional interrupt) is set when it is safe to send the next command. The property may only be set or read when in the powerup mode. Changes to this property take effect after the next tune is completed. Default: 0x14 AVC_MAX_GAIN 1 5 1 4 1 3 1 2 1 1 1 0 9876543210

0 MAXGAIN[14:0]

15 Reserved Always set to 0. 14:0 MAXGAIN[14:0] The maximum gain value for the AVC. MAXGAIN = g x 170. Range is 0– 32767. This implies that the range of g is 0–193 dB AM_FE_AGC_CONFIG 15:12 11:8 7 6 5 4 3 2 1 0 CCL000 0 FMMIX NOINTRU ATTENFM HA RMREJ INPUTSELECT[3:0] 0xF000 00 0 0 1 0 x 8 Bit Name Function 15:12 CCL Coupling Capacitor value at loop input. Default is 15 pF. 11:8 Reserved Always write 0. 7 Reserved Always write 0. 6 NOINTRU 0=In AM, external FM intrusion filter exists on AM antenna circuit. 1=In AM, FM attenuators are off. 5A T T E N F M 0=In AM, FM attenuators are turned on to improve FM intrusion. 1=In AM, FM attenuators are off. 4 HARMREJ 0=Harmonic reject is disabled. 1=Harmonic reject is enabled. 3:0 INPUTSELECT[3:0] 8=Receive signal co mes into the AMIL pin (loop antenna)

156 Rev. 0.3 Property 0x0708 AM_IF_AGC_ATTACK_MS Sets the number of milliseconds the IF high peak detector must be exceeded be fore attenuating the appropriate block. The peak detectors are only sampled once every 3–5 ms. If the peak detector trips, the internal counter is incremented by 4 ms. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read when in the powerup mode. Default: 80 Units: ms Property 0x0709 AM_IF_AGC_RELEASE_MS Sets the number of milliseconds the IF low p eak detector must not be exceeded before in creasing the gain of the appropriate block. The peak detectors are only sampled once every 3–5 ms. If the peak detector trips, the internal counter is incremented by 4 ms. The CTS bit (and optiona l interrupt) is set when it is safe to send the next command. This property may only be set or read when in the powerup mode. Default: 804 Units: ms AM_IF_AGC_ATTACK_MS 1 5 1 4 1 3 1 2 1 1 1 0 9 8 76543210 IF_AGC_ATTACK_MS[15:0] 0x0050 Bit Name Function 15:0 IF_AGC_ATTACK_MS[15:0] Number of milliseconds the IF high peak detector must be exceeded before attenuating the appropriate block. Range: 4–4096 ms. AM_IF_AGC_RELEASE_MS 1 5 1 4 1 3 1 2 1 1 1 0 9 8 76543210 IF_AGC_RELEASE_MS[15:0] 0x0324 Bit Name Function 15:0 IF_AGC_RELEASE_MS[15:0] Number of milliseconds the IF low peak detector must not be exceeded before increasing the gain of the appropriate block. Range: 4–4096 ms. Note: For best performance AM_IF_AGC_RELEASE_MS > AM_RF_AGC_RELEASE_MS and set AM_IF_AGC_RELEASE_MS to 804 ms for AM_RF_AGC_RELEASE_MS of 800 ms.

Rev. 0.3 157 Property 0x070C AM_RF_AGC_ATTACK_MS The AM_RF_AGC_ATTACK_MS property sets the number of milliseconds the wideband RF hi gh-peak detector must be exceeded before attenuating the appropriate block. The peak detectors are only sampled once every 3– 5 ms. If the peak detector trips, the internal counter is incremented by 4 ms. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 8 Units: ms Property 0x070D AM_RF_AGC_RELEASE_MS The AM_RF_AGC_RELEASE_MS property se ts the number of milliseconds th e wideband RF low-peak detector must not be exceeded before increasing the gain of the appropriate block. The peak detectors are only sampled once every 3–5 ms. If the peak detector trips, the in ternal counter is incremented by 4 ms. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 800 Units: ms AM_RF_AGC_ATTACK_MS 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 RF_AGC_ATTACK_MS[15:0] 0x0008 Bit Name Function 15:0 RF_AGC_ATTACK_MS[7:0] Number of milliseconds the wide-band RF high-peak detec- tor must be exceeded before attenuating the appropriate block. Default is 8 ms. Range is 4–4096 ms. AM_RF_AGC_RELEASE_MS 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 RF_AGC_RELEASE_MS[15:0] 0x0320 Bit Name Function 15:0 RF_AGC_RELEASE_MS[7:0] Number of milliseconds the wideband RF low-peak detector must not be exceeded before increasing the gain of the appropri- ate block. Default is 800 ms. Range is 4–4096 ms. Note: For best performance, AM_IF_AGC_RELEASE_MS > AM_RF_AGC_RELEASE_MS

158 Rev. 0.3 Property 0x070E AM_LNA_PD_THRESHOLD The AM_LNA_PD_THRESHOLD property sets the high thresh old and hysteresis for t he LNA peak detector. The high threshold sets the level at which the AGC increases attenuation. The hy steresis is how many dB below the high threshold the level must drop before the AGC decreases attenuation. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0x5104 AM_LNA_PD_THRESHOLD 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 HIGH[7:0] HYST[7:0] 0x51 0x04 Bit Name Function 15:8 HIGH[7:0] Sets the level in dBµV at which AGC increases attenuation. HIGH[7:0] Range: 79–93. 79 = 79 dBµV. 81 = 81 dBµV. 83 = 83 dBµV. 85 = 85 dBµV. 87 = 87 dBµV. 89 = 89 dBµV. 91 = 91 dBµV. 93 = 93 dBµV. 7:0 HYST[7:0] Sets how many dB below the high threshold the level must drop before the AGC decreases attenuation. HYST[7:0] Range: 3–6. 3=3 d B . 4=4 d B . 5=5 d B . 6=6 d B .

Rev. 0.3 159 Property 0x1100 AM_SEEK_BAND_BOTTOM The AM_SEEK_BAND_BOTTOM property se ts the bottom of the AM band for seek. Th e CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. The default is 520 kHz. Default: 520 Units: kHz Property 0x1101 AM_SEEK_BAND_TOP The AM_SEEK_BAND_TOP property sets the top of the AM band for seek. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. The default is 1710 kHz Default: 1710 Units: kHz AM_SEEK_BAND_BOTTOM 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 AMSKFREQL[15:0] 0x0208 Bit Name Function 15:0 AMSKFREQL[15:0] Sets the bottom of the AM band for seek. Default is 520 kHz. Range: 520–1710 (MW). 144–288 (LW). 2300–30000 (SW). AM_SEEK_BAND_TOP 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 AMSKFREQH[15:0] 0x06AE Bit Name Function 15:0 AMSKFREQH[15:0] Sets the top of the AM band for seek. Default is 1710 kHz. Range: 520–1710 (MW). 144–288 (LW) 2300–30000 (SW)

160 Rev. 0.3 Property 0x1102 AM_SEEK_FREQUENCY_SPACING The AM_SEEK_FREQUENCY_SPACING property selects freque ncy spacing for AM seek in multiples of 1 kHz. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. The default is 10 kHz. Default: 10 Units: kHz AM_SEEK_FREQUENCY_SPACING 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 0x000 AMSKSPACE[4:0] 0x000 0x0A Bit Name Function 15:5 Reserved Always write 0. 4:0 AMSKSPACE[4:0] Selects frequency spacing for AM seek. Default is 10 kHz. Range is 1–31. 5 = SW (5 kHz). 9 = AM in Asia (9 kHz). 9=L W ( 9k H z ) . 10 = AM in U.S. (10 kHz).

Rev. 0.3 161 Property 0x1200 AM_RSQ_INTERRUPT_SOURCE The AM_RSQ_INTERRUPT_SOURCE property configures inte rrupt related to Received Signal Quality metrics. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. The default is 0. Default: 0 AM_RSQ_INTERRUPT_SOURCE 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 0x000 SNRHINT SNRLINT RSSIHINT RSSILINT 0x000 0 0 0 0 Bit Name Function 15:4 Reserved Always write 0. 0: Disable Interrupt. 1: Enable interrupt to occur if SNR goes above the threshold set by AM_RSQ_SN- R_HIGH_THRESHOLD.

2 SNRLINT

0: Disable Interrupt. 1: Enable interrupt to occur if SNR goes below the threshold set by AM_RSQ_SN- R_LOW_THRESHOLD. 1R S S I H I N T 0: Disable Interrupt. 1: Enable interrupt to occur if RSSI goes above the threshold set by AM_R- SQ_RSSI_HIGH_THRESHOLD. 0R S S I L I N T 0: Disable Interrupt. 1: Enable interrupt to occur if RSSI goes below the threshold set by AM_R- SQ_RSSI_LO_THRESHOLD.

162 Rev. 0.3 Property 0x1201 AM_RSQ_SNR_HIGH_THRESHOLD The AM_RSQ_SNR_HIGH_THRESHOLD property sets the high threshold, which triggers the RSQ interrupt if the SNR is above this threshold. The CTS bit (and optional interr upt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 127 Units: dB Property 0x1202 AM_RSQ_SNR_LOW_THRESHOLD The AM_RSQ_SNR_LOW_THRESHOLD property sets low threshold, which triggers the RSQ interrupt if the SNR is below this threshold. The CTS bit (and optional interrup t) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: –128 Units: dB AM_RSQ_SNR_HIGH_THRESHOLD 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 0x00 SNRH[7:0] 0x00 0x7F Bit Name Function 15:8 Reserved Write 0 for (+) values, 0xFF for (–) values. 7:0 SNRH [7:0] Sets the high threshold, which triggers the RSQ interrupt if the SNR is above this threshold. Default is 127 dB. Range is –128 to 127 dB in steps of 1d B . AM_RSQ_SNR_LOW_THRESHOLD 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 0xFF SNRL[7:0] 0xFF 0x80 Bit Name Function 15:8 Reserved Write 0 for (+) values, 0xFF for (–) values. 7:0 SNRL [7:0] Sets low threshold, which triggers the RSQ interrupt if the SNR is below this threshold. Default is –128 dB. Range is –128 to 127 dB in steps of 1 dB.

Rev. 0.3 163 Property 0x1203 AM_RSQ_RSSI_HIGH_THRESHOLD The AM_RSQ_RSSI_HIGH_THRESH OLD property sets high threshold, which triggers the RSQ interrupt if the RSSI is above this threshold. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 127 Units: dBµV Property 0x1204 AM_RSQ_RSSI_LOW_THRESHOLD The AM_RSQ_RSSI_LOW_THRESHOLD property sets low threshold, which triggers the RSQ interrupt if the RSSI is below this threshold. The CTS bit (and optional interrup t) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: –128 Units: dBµV AM_RSQ_RSSI_HIGH_THRESHOLD 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 0x00 RSSIH[7:0] 0x00 0x7F Bit Name Function 15:8 Reserved Write 0 for (+) values, 0xFF for (–) values. 7:0 RSSIH [7:0] Sets high threshold, which triggers the RSQ interrupt if the RSSI is above this threshold. Default is 127 dBµV. Range is –128 to 127 dBµV in steps of 1d B . AM_RSQ_RSSI_LOW_THRESHOLD 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 0xFF RSSIL[7:0] 0xFF 0x80 Bit Name Function 15:8 Reserved Write 0 for (+) values, 0xFF for (–) values. 7:0 RSSIL [7:0] Sets low threshold, which triggers the RSQ interrupt if the RSSI is below this threshold. Default is –128 dBµV. Range is –128 to 127 dBµV in steps of 1d B .

164 Rev. 0.3 Property 0x1300 AM_ACF_INTERRUPT_SOURCE The AM_ACF_INTERRUPT_SOURCE property enables the ACF interrupt sources . The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0 AM_ACF_INTERRUPT_SOURCE 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 0x0000 HICUT_INT CHBW_INT SOFTMUTE_INT 0x0000 0 0 0 Bit Name Function 15:3 Reserved Always write 0. When set, enables the Hi-cut Interrupt. Default is 0. 0 = The Hi-cut interrupt is disabled. 1 = The Hi-cut interrupt is enabled. When set, enables the Channel Filter Bandwidth Interrupt. Default is 0. 0 = The Channel Filter Bandwidth interrupt is disabled. 1 = The Channel Filter Bandwidth interrupt is enabled. 0S O F T M U T E _ I N T When set, enables the softmute interrupt. Default is 0. 0 = The softmute interrupt is disabled. 1 = The softmute interrupt is enabled.

Rev. 0.3 165 Property 0x1301 AM_ACF_SM_THRESHOLD The AM_ACF_SM_THRESHOLD property sets the softmute in terrupt threshold in dB. When softmute attenuation rises above the level set by this property and the SOFTMUTE_INT interrupt is enabled through the AM_ACF_INTERRUPT_SOURCE property, the SOFTMUTE_IN T interrupt will be asserted. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 31 Units: dB Property 0x1302 AM_ACF_CHBW_THRESHOLD The AM_ACF_CHBW_THRESHOLD property sets the Channel Filter Bandwidth interrupt threshold in units of 100 Hz. When the channel filter bandwidth falls below this threshold and the CHBW_INT interrupt is enabled through the AM_ACF_INTERRUPT_SOURCE property, the CH BW_INT interrupt will be asserted. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0 Units: 100 Hz AM_ACF_SM_THRESHOLD 1 5 1 4 1 3 1 2 1 1 1 0 9 8 7 6 5 43210 0x000 SMATTN_THRESH[4:0] 0x000 0x1F Bit Name Function 15:5 Reserved Always write 0. 4:0 SMATTN_THRESH[4:0] Softmute interrupt threshold in dB which triggers the softmute interrupt when the softmute attenuation rises above this level. Default is 31 dB. Range is 0–31 dB. AM_ACF_CHBW_THRESHOLD 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 0x00 CHBW_THRESH[7:0] 0x00 0x00 Bit Name Function 15:8 Reserved Always write 0. 7:0 CHBW _THRESH[7:0] Channel Filter Bandwidth interrupt threshold in units of 100 Hz, which trig- gers the Channel Filter Bandwidth Interrupt when the channel filter band- width falls below this threshold. Default is 0 kHz. Range is 0–255.

166 Rev. 0.3 Property 0x1303 AM_ACF_HICUT_THRESHOLD The AM_ACF_HICUT_THRESHOLD property sets the Hi-cut in terrupt threshold in units of 100 Hz. When the Hi- cut cutoff frequency falls below this threshold and the Hi-cut_INT interrupt is enabled through the AM_ACF_INTERRUPT_SOURCE property, the Hi-cut_ INT inte rrupt will be asserted. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0 Units: 100 Hz Property 0x1306 AM_ACF_CONTROL_SOURCE The AM_ACF_CONTROL_SOURCE property determines if SNR or RSSI will be used as the controlling metric for ACF features. This will affect all automatically co ntrolled features that are cont rolled by SNR. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0 AM_ACF_HICUT_THRESHOLD 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 0x00 HICUT_THRESH[7:0] 0x00 0x00 Bit Name Function 15:8 Reserved Always write 0. 7:0 HICUT_THRESH[7:0] Hi-cut interrupt threshold in units of 100 Hz, which triggers the Hi Cut Inter- rupt when the Hi-cut cutoff frequency falls below this threshold. Default is 0 kHz. Range is 0–200. AM_ACF_CONTROL_SOURCE 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 0x0000 USE_RSSI 0x0000 0 Bit Name Function 15:1 Reserved Always write 0.

0 USE_RSSI

When set, RSSI will be used instead of SNR as the ACF controlling metric. 0 = Use SNR as the controlling metric. 1 = Use RSSI as the controlling metric.

Rev. 0.3 167 Property 0x2000 AM_VALID_MAX_TUNE_ERROR The AM_VALID_MAX_TUNE_ERROR property sets the maximum frequency error allowed in units of 2 ppm before setting the AFC rail indicator (AFCRL). The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 75 (150 ppm) Units: 2 ppm Property 0x2003 AM_VALID_SNR_THRESHOLD The AM_VALID_SNR_THRESHOLD property sets the SNR threshold for a valid AM Seek/Tune. If the desired channel SNR is above this threshold, then it is considered valid. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 5 Units: dB AM_VALID_MAX_TUNE_ERROR 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 0x00 AMMAXTUNEERR[7:0] 0x00 0x4B Bit Name Function 15:8 Reserved Always write 0. 7:0 AMMAXTUNEERR [7:0] Sets the maximum freq error allowed in units of 2 ppm before setting the AFC rail indicator (AFCRL). Default is 75. Range is 0–126. AM_VALID_SNR_THRESHOLD 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 0x00 AMVALSNR[7:0] 0x00 0x05 Bit Name Function 15:8 Reserved Write 0 for (+) values, 0xFF for (–) values. 7:0 AMVALSNR [7:0] Sets the SNR threshold for a valid AM Seek/Tune. Default is 5 dB. Range is –128 to 127 in steps of 1 dB. –128 = SNR is not used as a criterion in determining the validity of a station.

168 Rev. 0.3 Property 0x2004 AM_VALID_RSSI_THRESHOLD The AM_VALID_RSSI_THRESHOLD property se ts the RSSI threshold for a valid AM Seek/Tune. If the desired channel RSSI is above this threshold, then it is considered valid. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 10 Units: dBµV Property 0x2200 AM_CHBW_SQ_MIN_MAX The AM_CHBW_SQ_MIN_MAX property sets the maximum and minimum channel filter bandwidth in units of 100 Hz based on SNR or RSSI. To force a given channel filter bandwidth, set the min and max to the same value. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0x2314 Units: 100 Hz AM_VALID_RSSI_THRESHOLD 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 0x00 AMVALRSSI[7:0] 0x00 0x0A Bit Name Function 15:8 Reserved Write 0 for (+) values, 0xFF for (–) values. 7:0 AMVALRSSI[7:0] Sets the RSSI threshold for a valid AM Seek/Tune. Default is 10 dBµV. Range is –128 to 127 in steps of 1 dB. –128 = RSSI is not used as a criterion in determining the validity of a station. AM_CHBW_MIN_MAX 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 MAX[7:0] MIN[7:0] 0x23 0x14 Bit Name Function 15:8 MAX [7:0] Sets the maximum channel filter bandwidth in units of 100 Hz. Default is 3.5 kHz. Range is 15–50. 7:0 MIN [7:0] Sets the minimum channel filter bandwidth in units of 100 Hz. Default is 2 kHz. Range is 15–50.

Rev. 0.3 169 Property 0x2201 AM_CHBW_SQ_HIGH_THRESHOLD The AM_CHBW_SQ_HIGH_THRESHOLD property sets the S NR or RSSI threshold for maximum channel filter bandwidth. If the SNR or RSSI reported by the device is greater than the SQ High threshold programmed, then the channel filter bandwidth will be set to the maximum value programmed through Property 0x2200. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 30 Units: dB (for SNR), dBµV (for RSSI) Property 0x2202 AM_CHBW_SQ_LOW_THRESHOLD The AM_CHBW_SQ_LOW_THRESHOLD property sets the SN R or RSSI threshold for minimum channel filter bandwidth. If the SNR or RS SI reported by the device is less than the SQ Low threshold programmed, then the channel filter bandwidth will be set to the minimum value programmed through Property 0x2200. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 15 Units: dB (for SNR), dBµV (for RSSI) AM_CHBW_SQ_HIGH_THRESHOLD 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 SQMAX[6:0] 0x001E Bit Name Function 15:0 SQMAX[15:0] Sets the SNR or RSSI threshold for maximum channel filter bandwidth. Default is 30 dB. Range is 0–127 dB (or dBµV for RSSI). AM_CHBW_SQ_LOW_THRESHOLD 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 SQMIN[6:0] 0x000F Bit Name Function 15:0 SQMIN[15:0] Sets the SNR or RSSI threshold for minimum channel filter bandwidth. Default is 15 dB. Range is 0–127 dB (or dBµV for RSSI).

170 Rev. 0.3 Property 0x2203 AM_CHBW_SQ_WIDENING_TIME The AM_CHBW_SQ_WIDENING_TIME property sets the channel filter bandwidth widening time based on SNR or RSSI. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 2048 Units: ms Property 0x2204 AM_CHBW_SQ_NARROWING_TIME The AM_CHBW_SQ_NARROWING_TIME property sets the channel filter bandwidth narrowing time based on SNR or RSSI. The CTS bit (and optional interrupt) is set wh en it is safe to send the next command. This property may only be set or read in powerup mode. Default: 16 Units: ms AM_CHBW_SQ_WIDENING_TIME 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 WIDENING_TIME[15:0] 0x0800 Bit Name Function 15:0 WIDENING_TIME[15:0] Sets the SNR or RSSI based channel filter bandwidth widening time. Default is 2048 ms. Range is 1–32767 ms. AM_CHBW_SQ_NARROWING_TIME 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 NARROWING_TIME[15:0] 0x0010 Bit Name Function 15:0 NARROWING_TIME [15:0] Sets the SNR or RSSI based channel filter bandwidth narrowing time. Default is 16 ms. Range is 1–32767 ms.

Rev. 0.3 171 Property 0x2205 AM_CHBW_ASSI_MIN_MAX The AM_CHBW_ASSI_MIN_MAX property se ts the maximum and minimum channel filter bandwidth in units of 100 Hz. Based on adjacent signal strength indicator (ASS I.) To force a given channel filter bandwidth, set the min and max to the same value. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0x3232 Units: 100 Hz Property 0x2206 AM_CHBW_ASSI_LOW_THRESHOLD The AM_CHBW_ASSI_LOW_THRESHOLD prop erty sets the ASSI threshold in dB for maximum channel filter bandwidth. If the ASSI reported by the device is less th an the ASSI Low threshold programmed, then the channel filter bandwidth will be set to the maximum value programmed through Property 0x2205. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 10 Units: dB AM_CHBW_ASSI_MIN_MAX 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 MAX[7:0] MIN[7:0] 0x32 0x32 Bit Name Function 15:8 MAX[7:0] Sets the maximum channel filter bandwidth in units of 100 Hz. Default is 5 kHz. Range is 15–100. 7:0 MIN[7:0] Sets the minimum channel filter bandwidth in units of 100 Hz. Default is 5 kHz. Range is 15–100. AM_CHBW_ASSI_LOW_THRESHOLD 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 ASSIMIN[15:0] 0x000A Bit Name Function 15:0 ASSIMIN[15:0] Sets the ASSI threshold for maximum channel filter bandwidth. Default is 10 dB. Range is –128 to 127 dB.

172 Rev. 0.3 Property 0x2207 AM_CHBW_ASSI_HIGH_THRESHOLD The AM_CHBW_ASSI_HIGH_THRESHOLD prop erty sets the ASSI threshold in dB for minimum channel filter bandwidth. If the ASSI reported by the device is greater than the ASSI High threshold prog rammed, then the channel filter bandwidth will be set to the minimum value programmed through Property 0x2205. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 30 Units: dB Property 0x2208 AM_CHBW_ASSI_WIDENING_TIME The AM_CHBW_ASSI_WIDENING_TIME property sets the channel filter bandwidth widening time based on ASSI. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 16 Units: ms AM_CHBW_ASSI_HIGH_THRESHOLD 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 ASSIMAX[15:0] 0x001E Bit Name Function 15:0 ASSIMAX[15:0] Sets the ASSI threshold for minimum channel filter bandwidth. Default is 30 dB. Range is –128 to 127 dB. AM_CHBW_ASSI_WIDENING_TIME 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 WIDENING[15:0] 0x0010 Bit Name Function 15:0 WIDENING[15:0] Sets the channel filter widening time in ms. Default is 16 ms. Range is 1–32767 ms.

Rev. 0.3 173 Property 0x2209 AM_CHBW_ASSI_NARROWING_TIME The AM_CHBW_ASSI_NARROWING_TIME pr operty sets the channel filter bandwidth narrowing time based on ASSI. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 16 Units: ms Property 0x3100 AM_HICUT_SQ_HIGH_THRESHOLD The AM_HICUT_SQ_HIGH_THRESHOLD property sets the SNR or RSSI level at which Hi-cut begins to band limit. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 8 Units: dB (for SNR), dBµV (for RSSI) AM_CHBW_ASSI_NARROWING_TIME 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 NARROWING[15:0] 0x0010 Bit Name Function 15:0 NARROWING[15:0] Sets the channel filter narrowing time in ms. Default is 16 ms. Range is 1–32767 ms. AM_HICUT_SQ_HIGH_THRESHOLD 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 0x000 SQ_HIGH[6:0] 0x000 0x08 Bit Name Function 15:7 Reserved Always write 0. 6:0 SQ_HIGH[6:0] Sets the SNR or RSSI level at which Hi-cut begins to band limit. Default is 8. Range is from 0–127 dB (for SNR), dBµV (for RSSI).

174 Rev. 0.3 Property 0x3101 AM_HICUT_SQ_LOW_THRESHOLD The AM_HICUT_SQ_LOW_THRESHOLD property sets the SNR or RSSI level at which Hi-cut reaches maximum band limiting. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0 Units: dB Property 0x3102 AM_HICUT_ATTACK_TIME The AM_HICUT_ATTACK_TIME property sets the transitio n time in ms for which high cut lowers the cutoff frequency. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 16 Units: ms AM_HICUT_SQ_LOW_THRESHOLD 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 0x000 SQ_LOW[6:0] 0x000 0x08 Bit Name Function 15:7 Reserved Always write 0. 6:0 SQ_LOW[7:0] Sets the SNR or RSSI level at which Hi-cut reaches maximum band limiting. Default is 0. Range is from 0–127 dB (for SNR), dBµV (for RSSI). AM_HICUT_ATTACK_TIME 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 ATTACK[15:0] 0x0010 Bit Name Function 15:0 ATTACK[15:0] Sets the transition time in ms for which high cut lowers the cutoff frequency. Default is 16 ms. Range is 16–32767 ms.

Rev. 0.3 175 Property 0x3103 AM_HICUT_RELEASE_TIME The AM_HICUT_RELEASE_TIME prop erty sets the transition time in ms for which high cut increases the cutoff frequency. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 2000 Units: ms Property 0x3104 AM_HICUT_CUTOFF_FREQ The AM_HICUT_CUTOFF_FREQ property sets the maximum and minimum Hi-cut transition frequencies in units of 100 Hz. To force a given Hi-cut filter bandwidth, set the min and max to the same value. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0x280A Units: 100 Hz AM_HICUT_RELEASE_TIME 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 RELEASE[15:0] 0x07D0 Bit Name Function 15:0 RELEASE[15:0] Sets the transition time in ms for which high cut increases the cutoff frequency. Default is 2000 ms. Range is 16–32767 ms. AM_HICUT_CUTOFF_FREQ 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 MAX[7:0] MIN[7:0] 0x28 0x0A Bit Name Function 15:8 MAX [7:0] Maximum Hi-cut transition frequency in units of 100 Hz. Default is 4 kHz. Range is 10–50. 7:0 MIN [7:0] Minimum Hi-cut transition frequency in units of 100 Hz. Default is 1 kHz. Range is 10–50.

176 Rev. 0.3 Property 0x3105 AM_LOWCUT_MIN_FREQ The AM_LOWCUT_MIN_FREQ property sets the minimum cutoff frequency. The LowCut tracks the HICUT engine; therefore, thresholds are programmed in proper ty 0x3100 and 0x3101. Setting the property to 0 disables LowCut. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0A Units: Hz Property 0x3106 AM_LOWCUT_MAX_FREQ The AM_LOWCUT_MAX_FREQ property sets the maximu m cutoff frequency. The LowCut tracks the HICUT engine, therefore thresholds are programmed in property 0x3100 and 0x3101. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0A Units: Hz AM_HICUT_CUTOFF_FREQ 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 FREQ_MIN[15:0] 0x0000 Bit Name Function 15:0 FREQ_MIN[15:0] Sets the minimum LOW-CUT cutoff frequency in Hz. Default is disabled. Range is 0–1000 Hz. 0 = Disabled. AM_HICUT_CUTOFF_FREQ 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 FREQ_MAX[15:0] 0x0000 Bit Name Function 15:0 FREQ_MAX[15:0] Sets the maximum LOW-CUT cutoff frequency in Hz. Note that if property 0x3105 (AM_LOWCUT_MIN_FREQ) is non-zero, this property must be set to a value no less than property 0x3105. Default is 0 Hz. Range is 0–1000 Hz.

Rev. 0.3 177 Property 0x3300 AM_IBOC_CONTROL (Si47777 Only) The AM_IBOC_CONTROL property is the control prop erty for IBOC Blend. DIGITAL_IO_INPUT_SAMPLE_RATE and DIGITAL_IO_INPUT_FORMAT must be configured before IBOC Blend will function. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0x0000 Property 0x3301 AM_IBOC_ANALOG_TO_HD_CROSSFADE_TIME (Si4777 Only) The AM_IBOC_ANALOG_TO_HD_CROSSFADE_TIME property sets the crossfade time between full analog and full HD Digital audio in milliseconds. The CTS bit (and optiona l interrupt) is set when it is sa fe to send the next command. This property may only be set or read in powerup mode. Default: 1000 Units: ms AM_IBOC_CONTROL 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 0x00 FORCE 0x00 ENABLE 0x00 0 0x00 0 Bit Name Function 15:9 Reserved Always write 0. 8F o r c e Forces IBOC Blend. Default is 0. 0 = Do not force IBOC blend. The audio source is determined by the IBOC control pin. 1 = Force IBOC blend. The audio comes from IBOC system. 7:1 Reserved Always write 0. IBOC Blend Enable. Default is 0. 0 = The IBOC blend system is disabled. 1 = The IBOC blend system is enabled. AM_IBOC_ANALOG_TO_HD_CROSSFADE_TIME 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 TIME[15:0] 0x03E8 Bit Name Function 15:0 TIME[15:0] Sets the full analog to full digital crossfade time in ms. Default is 1000 ms. Range is 0–22000 ms.

178 Rev. 0.3 Property 0x3302 AM_IBOC_HD_TO_ANALOG_CROSSFADE_TIME (Si4777Only) The AM_IBOC_HD_TO_ANALOG_CROSSFADE_TIME property sets the crossfade time from full HD Digital to full analog audio in milliseconds. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 1000 Units: ms Property 0x3303 AM_IBOC_DYNAMIC_GAIN (Si47777 Only) The AM_IBOC_DYNAMIC_GAIN property sets the digital audio dynamic linear scaling factor. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0x007F AM_IBOC_HD_TO_ANALOG_CROSSFADE_TIME 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 TIME[15:0] 0x03E8 Bit Name Function 15:0 TIME[15:0] Sets the full digital to full analog crossfade time in ms. Default is 1000 ms. Range is 0–22000 ms. AM_IBOC_DYNAMIC_GAIN 1 5 1 4 1 3 1 2 1 1 1 0 987654 3210 0x00 DGAIN[7:0] 0x00 0x7F Bit Name Function 15:8 Reserved Always write 0. 7:0 DGAIN[7:0] Station dependent linear scaling factor in Q7 format. Range is 0–0x7F.

Rev. 0.3 179 Property 0x3304 AM_IBOC_STATIC_GAIN (Si4777 Only) The AM_IBOC_STATIC_GAIN property sets the digital audi o static linear gain factor. Reverse the sign of this number to obtain a 180 degree phase shift. The CTS bit (and optional interrupt) is set when it is safe to send the next command. This property may only be set or read in powerup mode. Default: 0x0100 AM_IBOC_STATIC_GAIN 1 5 1 4 1 3 1 2 1 1 1 0 9876543210 SGAIN[15:0] 0x0100 Bit Name Function 15:0 SGAIN[15:0] Static linear gain factor in Q7.8 format. Range is 0x8000–0x7FFF. RESP Bit Name Function 1 7:3 Reserved Values may vary. 1 2 HICUT_INT If set indicates that the Hi-cut cutoff frequency is below the Hi- cut threshold set by WB_ACF_HICUT_THRESHOLD. 1 1 CHBW_INT If set indicates that the Channel Filter Bandwidth is less than the threshold set by WB_ACF_CHBW_THRESHOLD. 1 0 SOFTMUTE_INT Is set Indicates that softmute attenuation has increased above the softmute threshold as set by WB_ACF_SM_THRESHOLD. 2 7:1 Reserved Values may vary. 20 S M U T E 0 = Audio is not soft muted. 1 = Audio is soft muted. 3 7:0 SMATTN[7:0] Soft mute attenuation level in dB. Range: 0–31. 4 7:0 CHANBW[7:0] Channel filter bandwidth in 100 Hz. Range: 0–150. 5 7:0 HICUT [7:0] Hi-cut cutoff frequency in units of 100 Hz. Range: 10–50.

Table summarizes descriptions and programming examples in this section. Table 18. Configuration and Operation Examples

10.1.1 Analog/Digital/MPX audio

10.1.2 IBOC HD Radio

10.1.3 AGC

10.1.4 Interrupts

10.1.5 Noise Blankers

10.1.6 Channel Equalizer

10.1.7 Pop Filter

10.1.8 Channel Filter Bandwidth

10.1.9 Softmute

10.1.10 Automatic Volume Control (AVC)

10.1.11 Blend

10.1.12 Hi-cut

10.1.13 Hi-blend

10.1.14 Primary/Companion

10.2.1 Tune

10.2.2 Seek

10.2.3 RDS

10.2.5 Check CTS and ERR

10.2.6 Check STC

The following tables summarize the available configuration options for AM and FM functions. Refer to section “9. Commands and Properties”for detailed descriptions of commands and properties. Table 19. FM Configuration Commands and Properties

Table 20. AM Configuration Commands and Properties

Rev. 0.3 183 10.1.1. Analog/Digital/MPX audio Analog, digital and MPX audio setup includes pin and sample rate (if applicable) configuration. 1. Complete steps up to and including 5 in section 5.1 Powerup one Receiver from Internal Memory or 10 in section 5.2 Powerup one Receiver from a Patch. 2. Send the ANA_AUDIO_PIN_CFG command to route analog left and right channel to LOUT/ROUT pins, or to route the MPX to the LOUT pin. This step may be omitted if analog audio is not required. Example: 1. Send the DIG_AUDIO_PIN_CFG command to configure DCLK, DFS and DOUT for digital audio in slave mode. Note that DCLK and DFS inputs should be stable before sending this command. This step may be omitted if digital audio is not required. Example: 1. Set property 0x0202 DIGITAL_IO_OUTPUT_SAMPLE_RATE to set the sample rate and 0x0203 DIGITAL_IO_OUTPUT_FORMATS to set the bit width and justification. This step may be omitted if digital audio is not required. 2. Proceed to other examples in this section. ANA_AUDIO_PIN_CFG Command Action Data Description CMD 0x1B ANA_AUDIO_PIN_CFG ARG1 0x02 2 = LOUT/ROUT pins config- ured to output audio. 3 = LOUT is configured for MPX out and ROUT is disabled. STATUS →0x80 DIG_AUDIO_PIN_CFG Command Action Data Description CMD 0x18 DIG_AUDIO_PIN_CFG ARG1 0x0A 0x0A = configure DCLK pin for digital audio slave mode. ARG2 0x0A 0x0A = configure DFS pin for digital audio slave mode. ARG3 0x0C 0x0C = configure DOUT pin for digital out. ARG3 0x00 0x00 = Do not modify the behavior of the BLEND pin. STATUS →0x80

conceptual diagram of the hardware interconnects. Figure 16. System Implementation of HD-Radio Reception with IBOC Blend on the Si47777

Set property 0x0301 AUDIO_MUTE.

Rev. 0.3 185 Example: 3. Set property 0x0200 DIGITAL_IO_INPUT_SAMPLE_RATES and 0x0202 DIGITAL_IO_OUTPUT_SAMPLE_RATE to configure the input and output digital sample rates. Example: 4. Send the DIG_AUDIO_PIN_CFG command to configure DCLK, DFS and DIN for I2S audio input in slave mode and the BLEND pin to select the mode of the audio combiner. Note that DCLK and DFS inputs SET_PROPERTY Command Action Data Description CMD 0x13 SET_PROPERTY ARG1 0x00 ARG2 0x03 0x0301 = AUDIO MUTE ARG3 0x01 ARG4 0x00 0x0003 = Mute left and right ARG5 0x03 STATUS →0x80 SET_PROPERTY Command Action Data Description CMD 0x13 SET_PROPERTY ARG1 0x00 ARG2 0x02 0x0200 = DIGITAL_IO_IN- PUT_SAMPLE_RATES ARG3 0x00 ARG4 0xAC 0xAC44 = 44.1 kHz ARG5 0x44 STATUS →0x80 SET_PROPERTY Command Action Data Description CMD 0x13 SET_PROPERTY ARG1 0x00 ARG2 0x02 0x0202 = DIGITAL_IO_OUT- PUT_SAMPLE_RATES ARG3 0x02 ARG4 0xAC 0xAC44 = 44.1 kHz ARG5 0x44 STATUS →0x80

186 Rev. 0.3 should be stable before sending this command. Example: 5. Send the ZIF_PIN_CFG command to configure IOUT, QOUT, IQCLK and IQFS pins for ZIF output in I2S master mode. Example: 6. Send the IC_LINK_GPIO_CTL_PIN_CFG command to configure DCLK2 and DOUT2 pins in I2S slave mode. Note that the DCLK2 input should be stable before sending this command. DIG_AUDIO_PIN_CFG Command Action Data Description CMD 0x18 DIG_AUDIO_PIN_CFG ARG1 0x0A 0x0A = configure DCLK pin 29 for digital audio in slave mode. ARG2 0x0A 0x0A = configure DFS pin 28 for digital audio in slave mode. ARG3 0x0D 0x0D = configure DIN pin 27 for digital in. ARG3 0x17 0x17 = configure BLEND pin 30 to select the mode of the audio combiner (analog or HD). STATUS →0x80 ZIF_PIN_CFG Command Action Data Description CMD 0x19 ZIF_PIN_CFG ARG1 0x15 0x15 = configure IQCLK pin 23 for I/Q output in master mode. ARG2 0x15 0x15 = configure IQFS pin 24 for I/Q output in master mode. ARG3 0x16 0x16 = configure IOUT pin 25 for I/Q output in master mode. ARG3 0x16 0x16 = configure QOUT pin 26 for I/Q output in master mode. STATUS →0x80

Rev. 0.3 187 Example: 7. Send the INTB_PIN_CFG command to configure DFS2 in I2S slave mode. Note that the DFS2 input should be stable before sending this command. In this example, the interrupt pin is set to the A1 pin. Note that only the A0 pin is available for I2C address selection in this mode. Note also that the interrupt pin can be moved to the A1 pin with a POWER_UP option. Example: 8. Enable the IBOC blend system. Proceed to other examples in this section. GPIO_CTL_PIN_CFG Command Action Data Description CMD 0x1A GPIO_CTL_PIN_CFG ARG1 0x00 ARG2 0x00 ARG3 0x0A 0x0A = Configure ICON pin as DCLK2 in slave mode. ARG4 0x0E 0x0E = Configure ICOP pin as DOUT2 in slave mode. STATUS →0x80 INTB_PIN_CFG Command Action Data Description CMD 0x1C INTB_PIN_CFG ARG1 0x0A 0x0A = Configure the DFS2 pin 18 for digital audio in slave mode. ARG2 0x28 0x28 = Configure the A1 pin as the interrupt. ARG3 0x00 ARG4 0x00 STATUS →0x80 SET_PROPERTY Command Action Data Description CMD 0x13 SET_PROPERTY ARG1 0x00 ARG2 0x33 ARG3 0x00 ARG4 0x00 ARG5 0x01 0x01 = enable STATUS →0x80

AGC peak detectors may be monitored by sending command 0x17 AGC_STATUS. FM AGC configuration involves setting signal routing, AGC and peak detector. 50 Ω LNA impedance as shown in Figure 17. Figure 17. FM Single Receiver System Diagram thresholds to 85 dBµV and 3 dB hysteresis, with an attack time of 4 ms and release time of 80 ms. expense of weak signal performance, the mixer peak detector thresholds may be decreased to as low as 79 dBµV.

AM AGC configuration involves configuring signal routing, AGC and peak detector characteristics. attack time of 80 ms and release time of 804 ms, RF attack time of 8 ms and RF release time of 800 ms. Property 0x0000 INT_CTL_ENABLE enables top-level interr upt sources and interrupt repetition characteristics. Channel Filter Bandwidth, Hi-blend, Hi-cut) interrupts. No te that Hi-blend only applies to FM mode operation. Property group 0x4000 configures RDS interrupts. Property 0x3400 enables and disables the FM multipath channel equalizer. Multi-path interference results in frequency-selective and frequency-flat fading of the FM signal at the receiver. differently in a channel. Frequency-selective fading gives rise to notches in the frequency response of the channel. restore the flat response of the channel. channel equalizer will be enabled. Table 21 summarizes the metric conditions that will enable the equalizer. Table 21. Equalizer Enable Conditions

190 Rev. 0.3 10.1.6. Channel Filter Bandwidth 10.1.6.1. FM Property group 0x2200 configures channel filter bandwidth characteristics for FM mode. Five independent channel filter bandwidth engines can be configured us ing RSSI (weak signal engine), ASSI100 (absolute value of difference betw een ±100 kHz channel RSSI ), ASSI200 (sum of ±200 kHz channel RSSI minus desired channel RSSI), and 200 kHz blocker deviation as the metric . For RSSI, ASSI100, and ASSI200, channel filter bandwidth ranging from minimum to maximum occurs at the specified widening rate as the metric increases above the minimum threshold and reaches maximum threshold. Channel filter bandwidth ranging from maximum to minimum occurs at the specified narrowing rate as the metric decreases below the maximum threshold and reaches the minimum threshold. For 200 kHz blocker deviation, channel filter bandwidth ranging from 80 to 32 kHz occurs at 1 ms rate as the metric increases above 75 kH z and reaches 100 kHz. Channel filter bandwidth ranging from 32 to 80 kHz occurs at the 300 ms rate as the metric decreases below 100 kHz and reaches 75 kHz. The resulting channel filter bandwidth is the minimum of the result of the five blend engine calculations. Property 0x220F FM_CHBW_WEAKSI G_THR is used to set th e hysteresis window for enabling the weak signal RSSI engine. The default is to enable above 16 dBuV RSSI and disable below 14 dBµV RSSI. Note that this hysteresis range is always determined by RSSI a nd is not configurable with the FM_ACF_CONTROL_SOURCE property. Property 0x2210 FM_CHBW_BLOCKER_THR is used to set the hysteresis window for engaging the 200 kHz blocker engine. The default is to enable above 20 dB ASSI200 and di sable below 10 dB ASSI200. Note that 2 dB ASSI200 indicates that the sum of t he energy at +200 kHz and –200 kHz is 20 dB greater than the desired channel. The 200 kHz blocker deviation engine is only en abled when sufficient pilot energy is present on the desired channel. 10.1.6.2. AM Property group 0x2200 configures channel filter bandwidth characteristics for AM mode. Two independent channel filter bandwidth engines can be configured using RSSI or SNR and ASSI (independent ±9/10 kHz channel RSSI relative to on-channel RSSI). Channel filter bandwidth ranging from minimum to maximum occurs at the specified widening rate as the metric increases above the minimum threshold and reaches maximum threshold. Channel filter bandwidth ranging from maximum to minimum occurs at the specified narrowing rate as the metric decreases below the maximum threshold and reaches the minimum threshold. The resulting channel filter bandwidth is the minimum of the result of the two blend engine calculations. Property 0x1306 AM_ACF_CONTROL_SOURCE is used to select RSSI or SNR as a metric for the channel filter bandwidth. 10.1.7. Softmute Property group 0x0400 configures softmute characteristics for FM and AM modes. Property 0x1306 FM_ACF_CONTROL_SOURCE (or AM_ACF_CONTROL_SOURCE is used to select SNR (default) or RSSI as a metric for the softmute engine. For FM and AM modes, the property is also used to select whether an AFC rail condition will engage softmute. The most common cause for an AFC rail condition is tuning to an idle channel. Softmute engages as SNR (or RSSI) drops below a tr igger threshold and audio level reaches a maximum attenuation at the end threshold. Softmute releases as SNR (or RSSI) rises above the end threshold and audio level reaches full level at the trigger threshold. The attack and release rates are configurable along with maximum attenuation and trigger and end thresholds.

Rev. 0.3 191 10.1.8. Automatic Volume Control (AVC) Property group 0x0500 configures automatic volume control (AVC) for AM mode. The AVC minimum and maximum gain can be configured. The AVC maintains a constant carrier level. 10.1.9. Mono/stereo Blend Property group 0x3500 configures the mono/stereo blend characteristics for FM mode. Three independent blend engines can be configured with rates using RSSI, multipath, and USN as the metric. Blend from minimum stereo to maximum stereo separation occurs at the specified attack rate as the metric increases above the minimum threshold and reaches maximum threshold. Blend from maximum stereo to minimum stereo separation occurs at the specified release rate as the metric decreases below the maximum threshold and reaches the minimum threshold. The resulting stereo separation is the minimum of the result of the six blend engine calculations. 10.1.10. Hi-cut Hi-cut applies a lowpass filter to the L+R MPX audio. 10.1.10.1. FM Property group 0x3600 configures the Hi-cut characteristics for FM mode. Three independent blend engines can be configured with ra tes using RSSI, multipath, and USN as the metric. Hi- cut from minimum to maximum occurs at the specified attack rate as the metric increases above the minimum threshold and reaches maximum threshold. Hi-cut from maximum to minimum occurs at the specified release rate as the metric decreases below the maximum threshold and reaches the minimum threshold. The resulting Hi-cut is the minimum of the result of the six blend engine calculations. 10.1.10.2. AM Property group 0x3100 configures the Hi-cut characteristics for AM mode. The blend engine can be configured with RSSI or SNR as the metric. Hi-cut from minimum to maximum occurs at the specified attack rate as the metric increases ab ove the minimum threshold and reaches maximum threshold. Hi-cut from maximum to minimum occurs at the specified release rate as the metric decreases below the maximum threshold and reaches the minimum threshold. 10.1.11. Hi-blend Hi-blend applies a lowpass filter to the L-R MPX audio. Property group 0x3700 configures the Hi-blend characteristics for FM mode. Three independent blend engines can be configured with ra tes using RSSI, multipath, and USN as the metric. Hi- blend from minimum to maximum occurs at the specified attack rate as the metric increases above the minimum threshold and reaches maximum threshold. Hi-blend from maximum to minimum occurs at the specified release rate as the metric decreases below the maximum threshold and reaches the minimum threshold. The resulting Hi- blend is the minimum of the result of the six blend engine calculations.

192 Rev. 0.3 10.2. Operation Operations including sending a command, checking CTS and ERR state, checking STC state, tune, seek, phase diversity receiver mode selection and RDS are possible. 10.2.1. Tune The tune operation provides options for configuring no rmal FM or HD bandwidth, tuning mode (validated normal tune, unvalidated fast tune) and audio filter state man agement (re-initialize based on new channel, or smoothly transition from current to new channel). In the case of tuning mode, 0x2000 property group sets the tune/seek metric thresholds and timing (RSSI, SNR, frequency error). Note that references to “AFC Rail” in this manual refers to a condition in which the frequency offset of the desired channel is outside the frequency error as configured with property group 0x2000. 1. Complete the appropriate steps in section “10.1. Configuration”. 2. Send the FM_TUNE_FREQ command to tune to a specific frequency. If the receiver has been muted (for example during IBOC HD configuration), set property 0x0301 to disable mute. Note that AM tuning is very similar. Refer to the AM_TUNE_FREQ command. 2. FM_TUNE_FREQ, or AM_TUNE_FREQ Start End 3. Check CTS & ERR 4. Check STC 1. Configure Tune parameters

Rev. 0.3 193 Example: 3. Check the CTS and ERR state to determine whether it is safe to send the next command. Refer to section “10.2.4. Check CTS and ERR Status”. 4. Check the STC state to determine tune status. Refer to section xxx Check STC state. 5. Repeat steps 2, 3, and 4 as necessary. FM_TUNE_FREQ Command Action Data Description CMD 0x30 FM_TUNE_FREQ ARG1 0x00 Normal bandwidth (vs. HD bandwidth), unconditionally stay on channel, initialize audio state based on new channel. ARG2 0x27 0x27A6 = tune to 101.50 MHz. ARG3 0xA6 ARG4 0x00 ARG5 0x00 STATUS →0x80 CTS = 1

194 Rev. 0.3 10.2.2. Seek 1. Complete the appropriate steps in section “10.1. Configuration”. 2. Set the 0x1100 property group to configure the seek start, stop and channel spacing. 3. Set the 0x2000 property group to set the tune/seek metric thresholds and timing (RSSI, SNR, frequency error). Note that because every system will have unique signal gain and noise characteristics, RSSI and SNR thresholds should be carefully evaluated. 4. Send the FM_SEEK_START command to begin the seek operation. Example: 5. Check the CTS and ERR state to determine whether it is safe to send the next command. Refer to section “10.2.4. Check CTS and ERR Status”. 6. Check the STC state to determine seek status and abort if desired. Refer to Check STC state. 7. Repeat steps 4, 5, and 6 as necessary. FM_SEEK_START Command Action Data Description CMD 0x30 FM_SEEK_START ARG1 0x08 Seek up, don’t wrap at the top of the band. STATUS →0x80 CTS = 1 4. FM_SEEK_START or AM_SEEK_START Start End 5. Check CTS & ERR 6. Check STC 1/2/3. Configure Seek parameters

Rev. 0.3 195 10.2.3. RDS 2. Set the 0x4000 property group to configure RDS Interrupts, FIFO size and management, and decoder configuration. 3. (Optional) Send the FM_RDS_BLOCKCOUNT command to verify RDS block error rate. The block error rate is defined as BLER = (UNCORRECTABLE + (EXPECTED-RECEIVED)) / EXPECTED. Example: FM_RDS_BLOCKCOUNT Command Action Data Description CMD 0x37 FM_RDS_BLOCKCOUNT ARG1 0x01 Clear the block count. STATUS →0x80 CTS = 1 RESP1 →0x00 RESP2 →0x27 Expected 0x271F = 10015 RESP3 →0x1F RESP4 →0x24 Received 0x248B = 9355 RESP5 →0x8B RESP6 →0x00 Uncorrectable 0x001B = 27 RESP7 →0x1B

196 Rev. 0.3 In this example, the BLER = (27 + (10015-9355)) / 10015 = 6.8%. 4. Send the FM_RDS_STATUS in response to a configured RDS interrupt or at a set time interval. For example, an interrupt can be configured when the 25 group FIFO has any number of entries between 1 and 25. Alternatively, the command can be sent every 88 ms (time for one group to be received) to 2.2 seconds (time for 25 groups to be received). The FM_RDS_STATUS command must be called once for each entry. The FIFOUSED field can be used to monitor FIFO status. Refer to the RDS and RBDS specifications for further decoding information. Example: 5. Repeat steps 3 and 4 as necessary. FM_RDS_STATUS Command Action Data Description CMD 0x36 FM_RDS_STATUS ARG1 0x01 Acknowledge the STC interrupt. STATUS →0x80 CTS = 1 RESP1 →0x00 RESP2 →0x1A TP/PTY has changed, PI has changed, synchronization has changed. RESP3 →0x05 PTY = 5 RESP4 →0x3E PI = 0x3E67 RESP5 →0x67 RESP6 →0x01 FIFO used = 1 (out of a maxi- mum of 25) RESP7 →0x00 BLEA = 0, BLEB = 0, BLEC = 0, BLED = 0 RESP8 →0x3E BLOCKA = 0x3E67 (PI code) RESP9 →0x67 RESP10 →0x20 BLOCKB = 0x20A7, group 2A (RadioText), PTY = 5, A/B flag = 0, text segment address code = 7 RESP11 →0xA7 RESP12 →0x6C BLOCKC = 0x6C74 (ASCII) = “lt” RESP13 →0x74 RESP14 →0x65 BLOCKD = 0x6572 (ASCII) = “er” RESP15 →0x72

Rev. 0.3 197 10.2.4. Check CTS and ERR Status After every command the CTS bit state should be checked to determine whether it is safe to send the next command and the ERR bit state should be checked to determine whether an error has occurred. 1. Start Timer Start 3. CTS = 1? 5. ERR = 0? 6. ERR = 0x18?No 6. Set CANCEL =1 and call FM_RSQ_STATUS or AM_RSQ_STATUS Yes 7. ERR = 0x20, 0x30 or 0x31?No 7. STOP Yes End Yes Yes No 6. Wait 5ms 4. Wait tCTS 2. Read STATUS and RESP1 4 .Timer > 125 ms?No No 4. STOP Yes 6. Set STCACK =1 and call FM_RSQ_STATUS or AM_RSQ_STATUS 6. Wait tCTS

Start a timer capable of measuring 100 µs to 125 ms.
Read the STATUS byte and RESP1.
If CTS is set, it is safe to send the next command. Go to step 5.
If CTS is not set, check if the timer measures greater than 125 ms (time to execute the POWER_UP

command plus 20% margin). If it does, it is likely that the receiver is not in the power up state. Refer to "5. CTS (100 µs). Refer to "8. Timing" on page 22.

If ERR (error) is set, check the specific error code reported in RESP1.
If the error code is 0x18, the tune or seek command is in progress and should be aborted by setting

(100 µs). Refer to "8. Timing" on page 22.

If the error code is 0x30 or 0x31 the boot operation failed and the powerup operation should be attempted.

Table 22. Error Codes and Remedies figure the part for ZIF output. error or incorrect device population. 0x18 Command Busy Wait for command completion, or abort tune/seek. 0x20 Bad internal memory In ternal memory corruption. Contact Silicon Labs. sequence with correct patch. with supported mode (AM, FM).

Rev. 0.3 199 10.2.5. Check STC Status After every command the STC (seek/tune complete) bit state should be checked to determine the state of the tune or seek command and abort the operation if desired. 1. Read the STATUS byte. 2. If STC (seek/tune complete) is set, set STCACK = 1 to acknowledge and clear the STC bit and set ATTUNE = 1 to return RSQ metrics from tune time and call FM_RSQ_STATUS (or AM_RSQ_STATUS). 1. Read STATUS Start 2. STC = 1? End 3. User Abort?No No 3. Set CANCEL =1 and call FM_RSQ_STATUS or AM_RSQ_STATUS Yes 3. Wait 5ms 2. Set STCACK =1, set ATTUNE = 1 and call FM_RSQ_STATUS or AM_RSQ_STATUS Yes 4. Wait tSTC 2. Wait tCTS

200 Rev. 0.3 Example: 3. If STC is not set and the user wishes to abort the tune, set CANCEL = 1 to abort and call FM_RSQ_STATUS (or AM_RSQ_STATUS). Wait 5 ms for the tune or seek to abort and set the STC bit. 4. Wait tSTC (21–40 ms depending AM or FM modes). Refer to "8. Timing" on page 22. FM_RSQ_STATUS Command Action Data Description CMD 0x32 FM_RSQ_STATUS ARG1 0x05 Return metrics from tune time, acknowledge the STC interrupt. STATUS →0x81 CTS = 1, STC = 1 RESP1 →0x00 RESP2 →0x31 SNR ready, RSSI ready, valid channel. RESP3 →0x27 Tuning frequency 0x027A6 =

101.50 MHz

RESP4 →0xA6 RESP5 →0x10 Frequency offset = 16 ppm RESP6 →0x25 RSSI = 37 dBµV RESP7 →0x14 SNR = 20 dB RESP8 →0x00 RESP9 →0xFB –100 kHz channel signal strength (LASSI) 0xFB = –5 dB RESP10 →0xF4 +100 kHz channel signal strength (HASSI) 0xFB = –12 dB RESP11 →0x0B Multipath 0x0B = 11 RESP12 →0x0F Reserved, va lues will vary. RESP13 →0x00 0x000 = Antenna capacitance, only for tracking filter applica- tions RESP14 →0x00 RESP15 →0xE5 ±200 kHz channel signal strength (ASSI) 0xE5 = –27 dB RESP16 →0x2A Ultrasonic noise (USN) 0x2A =

Rev. 0.3 201 DOCUMENT CHANGE LIST Revision 0.1 to Revision 0.2  Removed support for STRONGDEV, and 4 MHz crystal operation.  Added support for LowCut and ASSI-based VALID tune/seek check. Revision 0.2 to Revision 0.3  Updated " Property 0x2205 FM_CHBW_ASSI_MIN_MAX" on page 104.  Updated " Property 0x220A FM_CHBW_ASSI200_MIN_MAX " on page 106.  Updated " Command 0x32 FM_RSQ_STATUS" on page 64.  Updated " Property 0x0403 FM_SOFT_MUTE_RELEASE_TIME" on page 78.  Updated " Property 0x0404 FM_SOFT_MUTE_ATTACK_TIME" on page 78.  Updated " Property 0x4003 FM_RDS_CONFIDENCE" on page 136.  Updated " Property 0x0403 AM_SOFT_MUTE_RELEASE_TIME" on page 153.  Updated " Property 0x0404 AM_SOFT_MUTE_ATTACK_TIME" on page 154.

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Product Information

AN645 specifications and overview.

Summary

Si477X PROGRAMMING GUIDE

Description

Si477X PROGRAMMING GUIDE

Source title AN645 Datasheet(PDF) - Silicon Laboratories

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