CMI-8738

CMI-8738 CMEDIA | Alldatasheet

Document overview

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Technical content

Features

‹ HRTF-based 3D positional audio, supporting DirectSound™ 3D and A3D™ interface ‹ Supports rear side speakers, C3DX positional audio in 4 CH speaker mode ‹ Legacy audio SBPro™ compatible ‹ DLS-based wavetable music synthesizer, supports DirectMusic™ ‹ Built-in 32ohm Earphone buffer ‹ Drivers support EAX™, Karaoke Echo, Key Surround sound ‹ MPU-401 port ‹ Dual game port ‹ 16-bit full duplex CODEC ‹ 4 CH 16-bit DAC ‹ 32-bit PCI bus master ‹ External E²PROM interface ‹ Single chip design, +5V, 128 pins QFP Preliminary Ver 1.2 CMI-8738/PCI-SX C3DX PCI-Based HRTF 3D Extension Positional Audio Chip CMI-8738/PCI Block Diagram PCI interface PCI BUS DMA engine IRQ control Legacy audio SB16™emulator MPU 401 and GAME port Music Synthesizer HRTF DSP engine 16-bit CODEC Analog Mixer PLL and timing circuit 14.318Mhz Surround Earphone buffer LINE OUT MIC AMP LINE / CD / AUX / PCPSK IN MIC IN Rear L/R

C-MEDIA ELECTRONICS INC. Tel:886-2-87731100 Fax:886-2-87732211 URL : www.cmedia.com.tw Products and company names mentioned here are the trademarks of their respective owners. CMI-8738/PCI-SX AUDIO Specification Ver. 1.2 CMI8738 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 101 100 128 127 126 125 124 123 102 NC NC NC NC NC NC XBIO3 XBIO2 XBIO1 XBIO0 NC GND VDD GND XINTA NC XPRST XCLK33 XGNT XREQ XADOUTL XVREF XINTVREF AVDD AGND NC NC NC XOUT XIN VDD GND XA0 XA1 XA2 XA3 XA4 XA5 GND VDD XA27 GND VDD XA26 XA25 XA24 XCBE3 XIDSEL VDD GND XA23 XA22 XA21 XA20 XA19 GND VDD XA18 A17 XA16 XCBE2 XFRAME XIRDY XTRDY XDEVSEL VDD GND XSTOP XPAR XCBE1 NC VDDM DGND NC XGD7 XGD6 XGD5 XGD4 XGD3 XGD2 XGD1 XGD0 XRXD XTXD XGPBIO NC XMBCSZ XEECS VDD5V AGND AVDD XMICIN XPCSPKIN XAUXR XAUXL XLNR XLNL XREARR XREARL XCDR XA15 XA14 XA13 XA12 GND VDD XA11 XA10 XA9 XA8 XCBE0 XA7 XA6 XA29 XA30 XA31 GND VDD NC XA28 XADOUTR XADCHL XADCHR XLFILT XRFILT XCDGND XCDL NC PINOUT PINOUT CMI8738-037-SX AUDIO CHIP Q F P 1 2 8 P I N S

C-MEDIA ELECTRONICS INC. Tel:886-2-87731100 Fax:886-2-87732211 URL : www.cmedia.com.tw Products and company names mentioned here are the trademarks of their respective owners. CMI-8738/PCI-SX AUDIO Specification Ver. 1.2 DIGITAL PIN DESCRIPTION Name Number PIN Type Definition I/O PCI bus address and data lines XINTA 117 O Interrupt request , active-low. XPRST 119 I Reset XCLK33 120 I PCI bus clock. XGNT 121 I Bus master grant, active-low. XREQ 122 O Bus master request, tri-state output, active-low. XIDSEL 9 I ID select, active-high. XFRAME 23 I/O Cycle frame, active-low. XIRDY 24 I/O Initiator ready, active-low. The bus master device is ready to transmit or receive data XTRDY 25 I/O Target ready, active-low. The target device is ready to transmit or receive data XDEVSEL 26 I/O Device select, active-low. The target device has decoded the address of the current transaction as its own chip select range. XSTOP 29 I/O Stop transaction, active-low. The target device request to the master to stop the current transaction. XPAR 30 I/O Parity. The pin indicates even parity across XA31-XA9 and XCBE3-0 for both address and data phases. XCBE3,2,1,0 8,22,31,42 I/O Multiplexed command/byte enable. These pins indicate cycle type during the address phase of a transaction. VDD 4,10,18,27,37,45,54,115,124 +5V Di gital and PCI I/O power pin GND Digital and PCI I/O ground XIN 55 I 14.318Mhz crystal, or external clock input XOUT 56 O 14.318Mhz crystal XGD7-XGD4 97-94 I Game port switch input pin. Switch D to switch A XGD3-XGD0 93-90 I/O Game port resistor input pin. RC3 to RC0 XTXD 88 O MIDI transmit data XRXD 89 I MIDI receive data XBIO3-XBIO 109-112 I/O General purpose I/O VDD5V 83 +5V Digital and PCI I/O power pin VDDM 100 +5V Digital and PCI I/O power pin DGND 99 GND Digital and PCI I/O ground XEECS 84 O EEPROM chip select PIN DESCRIPTION

C-MEDIA ELECTRONICS INC. Tel:886-2-87731100 Fax:886-2-87732211 URL : www.cmedia.com.tw Products and company names mentioned here are the trademarks of their respective owners. CMI-8738/PCI-SX AUDIO Specification Ver. 1.2 AVDD 61,81 +5V Analog power AGND 60,82 GND Analog ground XADOUTL-R 64,65 AO1 Line out XADCHL-R 66,67 AI/O ADC filter XLFILT 68 AI/O Left channel DAC filter XRFILT 69 AI/O Right channel DAC filter XVREF 63 AI Reference Voltage (no use, left it floating) XINTVREF 62 AI Reference Voltage XCDL-R XCDGND 71,72,70 AI CD audio differential input XLNL-R 75,76 AI Line in or Rear speaker out XAUXL-R 77,78 AI Aux. Line in XPCSPKIN 79 AI PC beep signal XMICIN 80 AI Microphone in XREARL-R 73,74 AI/O Rear speaker out XGPBIO 87 O General purpose I/O pin XMBCSZ 85 I Audio chip select (low:enable) NC 57-59,86,98,101-108,113,118,1 - Reserved PIN DESCRIPTION ANALOG PIN DESCRIPTION

C-MEDIA ELECTRONICS INC. Tel:886-2-87731100 Fax:886-2-87732211 URL : www.cmedia.com.tw Products and company names mentioned here are the trademarks of their respective owners. CMI-8738/PCI-SX AUDIO Specification Ver. 1.2

ELECTRICAL CHARACTERISTICS

Ratings Symbol Value Units Digital power voltage VDD VDD±5% V Analog power voltage AVDD AVDD±5% V Operating temperature range TO 0 to 70 °C Storage temperature range TST -40 to 125 °C Maximum power dissipation PDMAX 300 MW Digital Characteristics PARAMETER Symbol Min Typ Max Unit Input high voltage(PCI I/O) VIH 2. VDD+0.5 V Input low voltage (PCI I/O) VIL -0.5 0.8 V Output high voltage VOH 2.4 VDD V Output low voltage VOL 0.0 0.2 0.4 V Output buffer current 5 mA Audio Characteristics PARAMETER Symbol Min Typ Max Unit Analog input voltage Avin 1.1 VRms Analog output voltage Avout 1.1 VRms A-A S/N ratio 85 db A-A THD 0.09 ADC S/N ratio 80 db ADC THD 0.1 0.2 % DAC S/N ratio 80 db DAC THD 0.1 0.2 % Microphone input level 20 200 mv Microphone booster 20 db

C-MEDIA ELECTRONICS INC. Tel:886-2-87731100 Fax:886-2-87732211 URL : www.cmedia.com.tw Products and company names mentioned here are the trademarks of their respective owners. CMI-8738/PCI-SX AUDIO Specification Ver. 1.2 CMI8738 PCI Configuration Spaces 00h 13F6 : ( Vender ID ) read only 02h 0111 : (Device ID) read only 04h 0006 : Command (State after #RST all is “ 0”) 0 (bit 9) Fast back-to-back enable 0 (bit 8) #SERR enable (R/W) 0 (bit 7) Wait cycle control 0 (bit 6) Parity error response 0 (bit 5) VGA palette snoop 0 (bit 4) Memory write and invalidate enable 0 (bit 3) Special cycles 1 (bit 2) Bus master (R/W) 0 (bit 1) Memory space 1 (bit 0) I/O space (R/W) 06h 0280 : Status 0 (bit 15) Detected Parity Error 0 (bit 14) Signaled System Error 0 (bit 13) Received Master Abort 0 (bit 12) Received Target Abort 0 (bit 11) Signaled Target Abort 01 (bits 10-9) DEVSEL timing 00-fast, 01-medium, 10-slow 0 (bit 8) Data Parity Error Detected 1 (bit 7) Fast Back-to-Back Capable 0 (bit 6) UDF Supported 0 (bit 5) 0-33MHz ,1-66MHZ Capable 00000 (bits 4-0) Reserved 08h 10 : Revision ID 09h 040100 : Audio device 0Ch 00 : Cache Line Size 0Dh 20 : Latency Timer 0Eh 80 : Header Type 0Fh 00 : BIST Configuration

C-MEDIA ELECTRONICS INC. Tel:886-2-87731100 Fax:886-2-87732211 URL : www.cmedia.com.tw Products and company names mentioned here are the trademarks of their respective owners. CMI-8738/PCI-SX AUDIO Specification Ver. 1.2 10h 0000d401 : I/O of length : -65280(ffff0100h) : First Base Address register 14h 00000000 : Uninitialized : Second Base Address register 18h 00000000 : Uninitialized : Third Base Address register 1Ch 00000000 : Uninitialized : Fourth Base Address register 20h 00000000 : Uninitialized : Fifth Base Address register 24h 00000000 : Uninitialized : Sixth Base Address register 28h 00000000 : Cardbus CIS Pointer 2Ch 13f6 : ( SubSystem Vender ID ) (R/W) 2Eh ffff : SubSystem ID (R/W) 30h 00000000 : Expansion ROM Base Address 34h 00000000 : Reserved 38h 00000000 : Reserved 3Ch 05 : Interrupt Line 3Dh 01 : Interrupt Pin 3Eh 02 : Min Grant 3Fh 18 : Max Latency DMA Slave Configuration Register(R/W) PCI Configuration address 40H Bit(s) Function 31:16 Reserved 15:4 Slave Base Address 15-4. INTEL VX chipset seleted if Base Address 15:4=000h

3 Non legacy Extended Addressing

0 = disabled 1 = enabled 2:1 Transfer Size 00 = 8 bit transfer 01 = 16 bit transfer 10 = 32 bit transfer, non legacy 11 = Reserved

0 Channel Enable

0 = disabled 1 = enabled Configuration Configuration

C-MEDIA ELECTRONICS INC. Tel:886-2-87731100 Fax:886-2-87732211 URL : www.cmedia.com.tw Products and company names mentioned here are the trademarks of their respective owners. CMI-8738/PCI-SX AUDIO Specification Ver. 1.2 Internal Register Mapping Function Control Register 0 Address 00H Bit(s) R/W Name Description 3 1 - 2 0 R e s e r v e d .

19 RST_CH1 Channel1, 1->Reset (Default 0)

18 RST_CH0 Channel0, 1->Reset (Default 0)

17 CHEN1 Channel1, 1->Enabled, 0->Disabled. 16 CHEN0 Channel0, 1->Enabled, 0->Disabled. 1 5 - 4 R e s e r v e d 3 PAUSE1 Channel1, 1->Pause if channel1 is enabled. 2 PAUSE0 Channel0, 1->Pause if channel0 is enabled.

1 CHADC1 Channel 1 , 1->Recording, 0->Playback

0 CHADC0 Channel 0, 1->Recording, 0->Playback

Function Control Register 1 Address 04H Bit(s) R/W Name Description 3 1 - 1 6 R e s e r v e d 15-13 DSFC[2:0] DAC Sampling Frequency Select, 0 0 0 5.512 K 0 0 1 11.025 K 0 1 0 22.05 K 0 1 1 44.1 K 1 0 0 8 K 1 0 1 16 K 1 1 0 32 K 1 1 1 48 K 12-10 ASFC[2:0] ADC Sampling Frequency Select, 0 0 0 5.512 K 0 0 1 11.025 K 0 1 0 22.05 K 0 1 1 44.1 K 1 0 0 8 K PCI register

C-MEDIA ELECTRONICS INC. Tel:886-2-87731100 Fax:886-2-87732211 URL : www.cmedia.com.tw Products and company names mentioned here are the trademarks of their respective owners. CMI-8738/PCI-SX AUDIO Specification Ver. 1.2 1 0 1 16 K 1 1 0 32 K 1 1 1 48 K 9 - 6 R e s e r v e d 5 INTRM Interrupt Mask bit for MCB (Master control block) module interrupt. 0 MCB interrupt disabled. 1 MCB interrupt enabled.

4 BREQ If this bit is set low it will prevent the MCB and DAC/ADC block

from accessing the memory.

0 Bus Master request disabled(power on state)

1 Bus Master request enabled. 3 VOICE_EN This bit enables Legacy V oice device(SB16,FM). 0 Legacy V oice disabled on channel 0. 1 Legacy V oice enabled on channel 0. 2 UART_EN This bit enables Legacy UART device.

0 UART disabled

1 UART enabled

1 JYSTK_EN This bit en ables Legacy Joystick device.

0 Joystick disabled

1 Joystick enabled

0 R e s e r v e d

Bit(s) R/W Name Description 31-24 VER[7:0] PCI Audio subversion for internal indentification. “01” 2 3 - 1 9 R e s e r v e d 18 FMOFFSET2 When set 1 and Reg. 24H bit7 ‘FMmute=1’,FM PCM will be forced to DC value 0002H. 1 7 - 1 6 R e s e r v e d 15-14 AdcBitLen[1:0] Sample resolution 00 16 Bits per sample . (Default) 01 15 Bits per sample. 10 14 Bits per sample. 11 13 Bits per sample. 13-12 AdcDacLen[1:0] Sample resolution 00 600nSec per bit in a sample. 01 660nSec per bit in a sample.

C-MEDIA ELECTRONICS INC. Tel:886-2-87731100 Fax:886-2-87732211 URL : www.cmedia.com.tw Products and company names mentioned here are the trademarks of their respective owners. CMI-8738/PCI-SX AUDIO Specification Ver. 1.2 10 1.3uSec per bit in a sample. (Default) 11 2.8uSec per bit in a sample.

11 CH1 Ssmple Rate 176K

10 CH1 Sample Rate 88K

9 CH0 Sample Rate 176K

8 CH0 Sample Rate 88K

3-2 CH1FMT[1:0] Data format of channel 1 00 8 bit Mono mode 01 8 bit Stereo mode 10 16 bit Mono mode 11 16 bit Stereo mode 1-0 CH0FMT[1:0] Data format of channel0 00 8 bit Mono mode 01 8 bit Stereo mode 10 16bit Mono mode 11 16 bit Stereo mode Interrupt Hold/Clear Register Address 0CH Bit(s) R/W Name Description 3 1 - 1 9 R e s e r v e d

18 TDMA_INT_EN Interrupt hold/clear bits for updating TDMA position

0 Interruupt Clear

1 Interrupt Hold if exist. 17 CH1_INT_EN Interrupt hold/clear bits for the Channel 1.

0 Interrupt Clear

1 Interrupt Hold if exist. 16 CH0_INT_EN Interrupt hold/clear bits for the Channel 0.

0 I n t e r r u p t C l e a r

1 Interrupt Hold if exist. 1 5 - 0 R e s e r v e d Interrupt Register Address 10H Bit(s) R/W Name Description 31 R INTR Interrupt reflected from any sources.

0 No interrupt

C-MEDIA ELECTRONICS INC. Tel:886-2-87731100 Fax:886-2-87732211 URL : www.cmedia.com.tw Products and company names mentioned here are the trademarks of their respective owners. CMI-8738/PCI-SX AUDIO Specification Ver. 1.2

1 Interrupt pending

27 R VCO

26 R MCBint Abort conditions occur during PCI Bus Target/Master Access.

0 Interrupt pending

16 R UARTint This bit is the UART interrupt bit.

0 No UART interrupt

1 UART interrupt pending

15 R LTDMAINT Interrupt for updating Low Channel TDMA position. 14 R HTDMAINT Interrupt for updation High Channel TDMA position. 0 No interrupt. 1 Interrupt pending. 1 3 - 8 R e s e r v e d

7 R XDO46 Direct programming EEPROM interface , read data register

6 R LHBTOG High/Low status from DMA CTRL register. 5 R LegHDMA Legacy is in High DMA channel. 4 R LegStereo Legacy is in Stereo mode. 3 R Ch1Busy Channel B Busy. 2 R Ch0Busy Channel A Busy. 1 R Chint1 Channel B Interrupt. 0 R Chint0 Channel A Interrupt. Legacy Control/Status Register Address 14H Bit(s) R/W Name Description 3 1 R e s e r v e d 30-29 VMPU [1:0] Base address for MPU401 access

00 Base address : 330h

01 Base address : 320h

10 Base address : 310h

C-MEDIA ELECTRONICS INC. Tel:886-2-87731100 Fax:886-2-87732211 URL : www.cmedia.com.tw Products and company names mentioned here are the trademarks of their respective owners. CMI-8738/PCI-SX AUDIO Specification Ver. 1.2

11 Base address : 300h

28 Reserved

27-26 VSBSEL[1:0] The Base Address Select for SB16 access.

00 Base address: 220h

01 Base address: 240h

10 Base address: 260h

11 Base address: 280h

25-24 FMSEL[1:0] The Base Address Select for FM access.

00 Base address : 388h

01 Base address : 3C8h

10 Base address : 3E0h

11 Base address : 3E8h

20 SetRetry Mode of wait state . 0:legacy I/O wait (default) 1:legacy I/O BUS retry 19 C_EEACCESS Direct programmi ng EEPROM interface Registers.

18 C_EECS

17 C_EEDI46

16 C_EECK46

Micellaneous Control Register A d d r e s s 1 8 H Bit(s) R/W Name Description 3 1 P W D P o w e r D o w n M o d e e n a b l e d . . 30 RESET Reset Bus Master/DSP Engine. 29-28 SFIL[1:0] Four level of filter control at the front end DAC..

27 TX/VX Which motherboard to work with

0 VX chip sets. 1 TX chip sets.

26 N4SPK3D Hardware copy front channel to rear channel

23 ENDBDAC Default low, High will enable Double DAC structure.

22 XCHGDAC Default low,

0 CH0 > Front SPKR, CH1 > Back SPKR. 1 CH0 > Back SPKR, CH1 > Front SPKR. 21-20 Reserved 19 FM_EN Legacy FM enabled.

C-MEDIA ELECTRONICS INC. Tel:886-2-87731100 Fax:886-2-87732211 URL : www.cmedia.com.tw Products and company names mentioned here are the trademarks of their respective owners. CMI-8738/PCI-SX AUDIO Specification Ver. 1.2 1 8 - 1 7 R e s e r v e d 16 VIDWPDSB Sub ID write protect disabled. (default 0) 1 5 R e s e r v e d 14 MASK_EN Activate ch annel mask on Legacy DMA.

0 Disabled

1 Enabled

13 VIDWPDSB Write Protect of HSP Configuration Sub ID. 0 Protect. 1 No protect. 12 SFILENB Let software contrl filter stepping at the front end DAC. 1 1 - 5 R e s e r v e d 4 MIDSMP Enable 1/2 interpolation at the Front end DAC.. 3-2 UPDDMA[1:0] For every the number of samples to notify updating TDMA position.

00 Every 2048 samples

01 Every 1024 samples

10 Every 512 samples. 11 Every 256 samples. 1-0 TWAIT[1:0] For controling the length of legacy BUS cycle. 00 3 PCICLK. 01 18 PCICLK. 10 24 PCICLK 11 32 PCICLK * Notice REQ_SQ[2:0] States of BusRequest Engine. MM_DATA Bus Master is using Bus. M I D L E B u s M a s t e r i s n o t u s i n g B u s . REQA/REQB Channel 0/1 BusMaster Request. GNTA/GNTB Channel 0/1 BusMaster Grant. ADRQ/BDRQ Channel 0/1 DMA Request. ADACK/BDACK Channel 0/1 DMA Acknoledge. AIRQ/BIRQ Channel 0/1 Interrupt. CX/BX Channel 0/1 Busy. T - DMA Position Address 1CH Bit(s) R/W Name Description 31-16 R TDMACN T Current Byte/Word Count of DMA channel. 15-0 R TDMAADR Current Address of DMA channel.

C-MEDIA ELECTRONICS INC. Tel:886-2-87731100 Fax:886-2-87732211 URL : www.cmedia.com.tw Products and company names mentioned here are the trademarks of their respective owners. CMI-8738/PCI-SX AUDIO Specification Ver. 1.2 Mixer Control / Device Configure Register (can be accessed only by BYTE instruction) Address 20H Bit(s) R/W Name Description 7-0 W SBVR[7:0] Programmable SB16 version No. R DEV[7:0] Hardwire device version No. Address 21H Bit(s) R/W Name Description 7 - 3 R e s e r v e d 2 X_ADPCM SB16 ADPCM enable,default disabled. 1 PROINV SBPro Left/Right channel switching.

0 X_SB16 Indicate device active as SB16 compatible, default SB16

Bit(s) R/W Name Description 7-0 IDXdata Mapping SB compatible mixer INDEX register data port(A2x5h) Address 23H Bit(s) R/W Name Description 7-0 IDXaddr Mapping SB compatible mixer INDEX register address port(A2x4h) Address 24H Bit(s) R/W Name Description

7 Fmmute Mute FM

6 Wsmute Mute Wave stream

5 SPK4 select four speaker mode(emulate Line in to Line out )

4 Rear2front exchange rear and front channels’s speaker out

3 Waveinl Digital Wave recording Left channel

2 Waveinr Digital Wave recording Right channel

Bit(s) R/W Name Description

7 RAUXREN Recording source select R-Aux

6 RAUXLEN Recording source select L_Aux

5 VAUXRM R-AUX mute control

4 VAUXLM L-AUX mute control

C-MEDIA ELECTRONICS INC. Tel:886-2-87731100 Fax:886-2-87732211 URL : www.cmedia.com.tw Products and company names mentioned here are the trademarks of their respective owners. CMI-8738/PCI-SX AUDIO Specification Ver. 1.2 3-1 VADMIC[2:0] Recording MIC volume control

0 MICGAINZ MIC gain control,default high disable

Bit(s) R/W Name Description 7-4 VAUXL[3:0] L- AUX volume control 3-0 VAUXR[3:0] R-AUX volume control Address 27H Bit(s) R/W Name Description 0 DMAUTO SB16 Low/High DMA Auto detect enabled ,When high.

1 R e s e r v e d

2 XGPBIO general purpose bi-direction pin, when high output tri-state

(default LOW)

3 Reserved

4 Reserved

5 XGPO1 general purpose output pin 1,this pin shared with XSPDIFO pin,

and enabled when index reg. F0_bit 0 programmed high. 6-7 Reserved Mup401 PCI Port Index address 40-4FH FM PCI Port Index address 50-5FH Extension Index Register (access from SB compatible mixer port) Index address F0H Bit(s) R/W Name Description 7-5 VPHONE[2:0] Phone volume control

4 VPHOM Phone mute control

3 VSPKM PC-Speaker mute control,default high unmute

2 RLOOPREN Recording R-channel enable

1 RLOOPLEN Recording L-channel enable

0 VADMIC3 Micphone record boost, default low disable, high enable. Index address F8-FFH These 8 registers is used to programming M/N conunter by clock generator

C-MEDIA ELECTRONICS INC. Tel:886-2-87731100 Fax:886-2-87732211 URL : www.cmedia.com.tw Products and company names mentioned here are the trademarks of their respective owners. CMI-8738/PCI-SX AUDIO Specification Ver. 1.2 Channel 0 Frame Register 1 Address 80H Bit(s) R/W Name Description 31-0 W BASADDR0 Base address of channel 0. R CURADDR0 Current address of channel 0. Channel 0 Frame Register 2 Address 84H Bit(s) R/W Name Description 31-16 W BASCNT0 Base count of samples at Codec. 15-0 W BASCNT0 Base count of samples at Bus Master. 31-16 R CURCNT0 Current count of samples at Codec. 15-0 R CURCNT0 Current count of samples at Bus Master. Channel 1 Frame Register 1 Address 88H Bit(s) R/W Name Description 31-0 W BASADDR1 Base address of channel 0. R CURADDR1 Current address of channel 0. Channel 1 Frame Register 2 Address 8CH Bit(s) R/W Name Description 31-16 W BASCNT1 Base count of samples at Codec. 15-0 W BASCNT1 Base count of samples at Bus Master. 31-16 R CURCNT1 Current count of samples at Codec. 15-0 R CURCNT1 Current count of samples at Bus Master.

C-MEDIA ELECTRONICS INC. Tel:886-2-87731100 Fax:886-2-87732211 URL : www.cmedia.com.tw Products and company names mentioned here are the trademarks of their respective owners. CMI-8738/PCI-SX AUDIO Specification Ver. 1.2 Legacy SB compatible mixer Index D7 D6 D5 D4 D3 D2 D1 D0 0x00 Reserved 0x04 Wave volume left channel Wave volume right channel 0x0A Mic volume 0x22 Master volume left channel Master volume right channel 0x26 FM volume left channel FM volume right channel 0x28 Analog-CD volume left channel Analog-CD volume right channel 0x2E Line-in volume left channel Line-in volume right channel 0x30 Reserved 0x31 Reserved 0x32 Reserved 0x33 Reserved 0x34 Reserved 0x35 Reserved 0x36 Reserved 0x37 Reserved 0x38 Reserved 0x39 Reserved 0x3A Reserved 0x3B PC spk volume Output muting controls 0x3C Line L Line R CD L CD R Mic Recording left channel controls 0x3D FM L FM R Line L Line R CD L CD R Mic Recording right channel controls 0x3E FM L FM R Line L Line R CD L CD R Mic 0x3F Reserved 0x40 Reserved 0x41 Reserved 0x42 Reserved 0x43 Reserved 0x44 Reserved 0x45 Reserved 0x46 Reserved 0x47 Reserved IRQ channel (read only) 0x80 IRQ10 IRQ7 IRQ5 IRQ2(9) 16 bit DMA channel (read only) 8 bit DMA channel (read only) 0x81 DMA 7 DMA 5 DMA 3 DMA 1 DMA 0 Interrupt status (read only) 0x82 MPU-40 16bit DMA 8bit DMA z Please do not write any values into reserved registers

C-MEDIA ELECTRONICS INC. Tel:886-2-87731100 Fax:886-2-87732211 URL : www.cmedia.com.tw Products and company names mentioned here are the trademarks of their respective owners. CMI-8738/PCI-SX AUDIO Specification Ver. 1.2 1. Stereo It is only one-dimensional, as sounds come from (left /right) the physical location of speakers. 2. Surround (Stereo Expander ) It filters the existing stereo signal to make the sounds fill in the area around the speakers, and in front of the listener. Sound sources appear to come from outside the physical locations of the speakers. 3. Multi-Speaker Surround (Dolby Pro Logic or Digital AC-3) It uses five speakers instead of two to surround the listener; hence, sound sources come from five directions and create engaging audio experience. This surround sound effect, however, has to be pre-recorded, and it dose not support interactive environment. Audio Processing Technology

C-MEDIA ELECTRONICS INC. Tel:886-2-87731100 Fax:886-2-87732211 URL : www.cmedia.com.tw Products and company names mentioned here are the trademarks of their respective owners. CMI-8738/PCI-SX AUDIO Specification Ver. 1.2 4. HRTF 3D Positional 3D (C-Media 3D) Only this sound processing technology can be called real 3D manifestation, as 3D usually refers to the three dimensions of X, Y and Z. This technology allows people to pin-point the location of sound in the real world (up/down, left/right, front/back)using only two speakers or a pair of headphones. This te chnology also supports interactive 3D applications to get a real-time placement of sounds via API (application programming interface) such as Microsoft DirectSound3D TM. We can also use this technology to simulate Multi-speaker Surround with two physical speakers to deliver five “virtual" speakers in the air, surrounding the listener and creating home theater sound environment. This is the most economical and the easiest solution to people who would like to get high performance surround sound but don’t want to spend money in adding extra speakers. A virtual speaker A physical speaker Audio Processing Technology

C-MEDIA ELECTRONICS INC. Tel:886-2-87731100 Fax:886-2-87732211 URL : www.cmedia.com.tw Products and company names mentioned here are the trademarks of their respective owners. CMI-8738/PCI-SX AUDIO Specification Ver. 1.2 5. HRTF 3D Extension Positional (C-Media 3DX) 3D illusion exists because traditional 3D positional audio system assumes the user's position as the sweet spot to design crosstalk-cancellation circuit; therefore, if the user wants to have 3D positional audio effects, he can’t move his head or position out of sweet spot. Another 3D illusion fails because half the population are compulsive "head-turners" who will never get 3D audio from two speakers . To remedy this, C-Media utilizes HRTF 3D extension technology (C3DX) to enhance traditional HRTF 3D positional audio by substituting two-speaker system by four-speaker one. Therefore, at least one or two speakers should be placed behind the listener's head to complement the rear-side effect, thus creating compelling realistic sound. This technology greatly improves HRTF 3D positional audio quality, and successfully eliminates the sweet spot limitation. Users can enjoy the real 3D audio gaming effects, and don't have to worry about the environmental confinement any more. A virtual speaker A physical speaker Audio Processing Technology

C-MEDIA ELECTRONICS INC. Tel:886-2-87731100 Fax:886-2-87732211 URL : www.cmedia.com.tw Products and company names mentioned here are the trademarks of their respective owners. CMI-8738/PCI-SX AUDIO Specification Ver. 1.2 C3D HRTF Positional Audio Technology C3D technology uses an audio filter called Head Related Transfer Functions (HRTFs), which is licensed from CRL®(Central Research Lab). The basic concept of C3D is: since we can hear sound three dimensionally in the real world using our two ears, it must be possible to regenerate the same sound effect from two loud speakers. What is HRTF ? HRTF (Head Related Transfer Functions) is a set of audio filters which can vary locations of sound effects (spatial hearing cues) in three-dimension measured from the listener's eardrum. People can use this technology and special digital signal processing to re-create spatial hearing cues, so as to makes the ears hear a realistic and three-dimensional sounds coming from a pairs of loud speakers or headphones. There are several listening cues which allow people to hear sounds three-dimensionally : (I). Spatial Hearing : Primary 3D-cues 1. IAD The head shadowing effect creates differences in the amplitudes of the sound signals arriving at each ear from the source. The effects of diffraction are most noticeable in the range between about 700 Hz to 8 KHz, where the A and S functions periodically converge and diverge gently. This Inter-aural Amplitude difference (IAD) is one of the primary 3D sound cues. HRTF 3D Positional Audio Technology White-Paper

C-MEDIA ELECTRONICS INC. Tel:886-2-87731100 Fax:886-2-87732211 URL : www.cmedia.com.tw Products and company names mentioned here are the trademarks of their respective owners. CMI-8738/PCI-SX AUDIO Specification Ver. 1.2 2. ITD In addition to IAD, there is also a time-of-arrival difference between the left and right ears(unless the sound source is in one of the pole positions, such as directly in front, behind, above and below): this is known as the Inter-aural Time Delay (ITD). HRTF 3D Positional Audio Technology White-Paper

C-MEDIA ELECTRONICS INC. Tel:886-2-87731100 Fax:886-2-87732211 URL : www.cmedia.com.tw Products and company names mentioned here are the trademarks of their respective owners. CMI-8738/PCI-SX AUDIO Specification Ver. 1.2 3. Pinna Effects It has been presumed by several researchers that the convolutions of the pinna create the spectral features which constitute the 'height' cues. In practical experiments by Gardner, in which different parts of the pinna were occluded, and then the ability of a number of subjects to identify sound source positions at different heights was tested, it was shown that the different features all contributed by different amounts. For example, if the fossa is excluded, then height localization capability is impaired, but not totally extinguished. It would be reasonable to conclude that it is the combined effect of the pinna convolutions which create the various localization cues, and it is not valid - or logical - to attempt to assign particular spatial capabilities with individual physical features. (II). Spatial Hearing : Secondary 3D -cues (shoulder & local reflections) In addition to the 'primary' 3D sound cues (IAD, ITD and pinna effects), there are several additional cues which do contribute to the localization capability; these will be referred to here as 'secondary' cues, and include shoulder/torso reflections, local room reflections, and psychological cues. 1. Shoulder / Torso reflections The presence of a torso attached to an artificial head has the effect of increasing the pressure in the vicinity of the ear up to frequencies of around 2 kHz. The effect is greater for frontal sources than lateral ones. In experience, the presence of the torso does not appear to contribute much to spatial accuracy. However, shoulders are located very close to the ears, and their effect is greater, this time, in respect of HRTF 3D Positional Audio Technology White-Paper

C-MEDIA ELECTRONICS INC. Tel:886-2-87731100 Fax:886-2-87732211 URL : www.cmedia.com.tw Products and company names mentioned here are the trademarks of their respective owners. CMI-8738/PCI-SX AUDIO Specification Ver. 1.2 lateral sounds. If one listens to an artificial head first without - and then with - shoulder fitments, then it is clear that the shoulders do contribute to spatial effects in certain positions. The shoulders provide a strong reflection from lateral sources, with a short path-length of around 10 cm between direct sound and reflection. The effects are most important for side-positioned sources, especially for "height" effects, where the shoulders tend to mask sources which move below about 30 degree depression. 2. Local, Room Reflections In simulations, it is clear that the incorporation of first-order simulated room reflections can help in the creation of sound images which have a "solid" nature. However, the effects - if accurately simulated - are relatively slight. Experience has shown that it is primarily the quality of the HRTFs themselves which determine the quality and solidity of the sound image. The further addition of second-order reflections does not help significantly, because in reality, there is a great number of reflections in the average room. A method which does help to recreate the acoustic experience of a room, however, is to use approximate simulations of lateral reverb, using either 2 or 4 laterally placed "virtual" sources at, say, +-70 degrees and 80 degrees azimuth.

• The quality of the sound image relates to the HRTFs used.
• The quality of the room image relates to addition of reflections and reverb. 3. Psychological Cues There are clearly psychological cues present in everyday life which work together with the audio cues to tell us about the world around us. For example, if you hear the sound of a helicopter flying, you expect it to be up in the air, and not downwards. If a dog is barking nearby, you would expect it to be downwards. HRTF 3D Positional Audio Technology White-Paper

C-MEDIA ELECTRONICS INC. Tel:886-2-87731100 Fax:886-2-87732211 URL : www.cmedia.com.tw Products and company names mentioned here are the trademarks of their respective owners. CMI-8738/PCI-SX AUDIO Specification Ver. 1.2 How to listen to C3D sound correctly and properly? 1. Use Headphones to Have Much Better Effect When you use headphones in listening, there will be less interference such as outside voices or room reflections comparing to using speakers. 2. Choose Correct Output Devices Choose the correct output devices in the options of demo program in accordance with what listening devices you want to listen to. Listening through speakers must be proceeded by crosstalk-cancellation, so if you choose the wrong output devices, there won’t be any 3D positional audio effect. HRTF 3D Positional Audio Technology White-Paper

C-MEDIA ELECTRONICS INC. Tel:886-2-87731100 Fax:886-2-87732211 URL : www.cmedia.com.tw Products and company names mentioned here are the trademarks of their respective owners. CMI-8738/PCI-SX AUDIO Specification Ver. 1.2 3. Position of Speakers If you listen from speakers, please do not reverse the left and right speakers, which should be put in equal distance from the listener. That is, the listener, the left, and the right speaker must be in the topmost of a right triangle. The position of the listener is called the “sweet spot”. In addition, the height of the listener’s ears must be equal to that of the speakers. 4. Turn Surround Sound Functions off When the surround sound effect is enabled, it will cause confusion with C3D sound, and make positional sound effect invalid. HRTF 3D Positional Audio Technology White-Paper

C-MEDIA ELECTRONICS INC. Tel:886-2-87731100 Fax:886-2-87732211 URL : www.cmedia.com.tw Products and company names mentioned here are the trademarks of their respective owners. CMI-8738/PCI-SX AUDIO Specification Ver. 1.2 Audio Rack Panel Audio Rack Panel Two Speakers System : Four Speakers System :

4 Speakers

C-MEDIA ELECTRONICS INC. Tel:886-2-87731100 Fax:886-2-87732211 URL : www.cmedia.com.tw Products and company names mentioned here are the trademarks of their respective owners. CMI-8738/PCI-SX AUDIO Specification Ver. 1.2 CMI8738 PCI Audio Adapter Layout Notes 1. The wires of analog circuits(chip pin64-80) must be wider than 12mil. 2. The whole PCB grounding should be well-organized(The ground must be placed as much as possible. Also, the gr ound of both the component and the solder sides should be drilled as much as possible.). 3. The grounding under CMI8738 should be well-organized as mentioned above. 4. The regulator(78L05) must be placed near the chip as much as possible. 5. The chip and the circuits need independent power supply regulators to prevent insufficient currents.