Audio Codec '97
AC ‘97 Component Specification Revision 2.3 Rev 1.0
4
4.3.9 Slot 8: PCM R Surround DAC (or PCM R n+1) ................................................................................32
4.3.10 Slot 9: PCM LFE DAC .......................................................................................................................32
4.3.11 Slot 10: Modem Line 2 Output Channel (or PCM L n+1, or S/PDIF output) ....................................32
4.3.12 Slot 11: Modem Handset Output Channel (or PCM R n+1, or S/PDIF output).................................32
4.3.13 Slot 12: Modem GPIO Control Channel (or PCM C n+1).................................................................32
4.3.14 Double Rate Audio in Slots 7, 8 or 10-12 ............................................................................................32
4.4 AC-LINK INPUT FRAME (SDATA_IN)........................................................................................................32
4.4.1 Slot 0: TAG ..........................................................................................................................................34
4.4.2 Slot 1: Status Address Port / SLOTREQ signaling bits.......................................................................34
4.4.2.1 Status Address Port .......................................................................................................................................... 34
4.4.2.2 SLOTREQ signaling bits ................................................................................................................................. 35
4.4.3 Slot 2: Status Data Port ......................................................................................................................35
4.4.4 Slot 3: PCM Record Left Channel ......................................................................................................35
4.4.5 Slot 4: PCM Record Right Channel....................................................................................................35
4.4.6 Slot 5: Modem Line 1 ADC..................................................................................................................36
4.4.7 Slot 6: Dedicated Microphone Record Data........................................................................................36
4.4.8 Slots 7-9: Vendor Reserved.................................................................................................................36
4.4.9 Slot 10: Modem Line 2 ADC................................................................................................................36
4.4.10 Slot 11: Modem Handset ADC.............................................................................................................36
4.4.11 Slot 12: Modem GPIO Status...............................................................................................................36
4.5 AC-LINK INTEROPERABILITY REQUIREMENTS AND RECOMMENDATIONS ....................................................36
4.5.1 “Atomic slot” Treatment of Slot 1 Address and Slot 2 Data ...............................................................36
4.5.2 Codec Register Status Reads ...............................................................................................................37
4.5.3 Codec Register Status Read Completion Latency................................................................................37
4.5.4 The Codec-Ready Bit and Audio or Modem DAC/ADC Status Bits.....................................................38
5. Audio Features...................................................................................................................................................38
5.1 OVERVIEW....................................................................................................................................................38
5.2 LINE_OUT AND AUX_OUT.......................................................................................................................39
5.2.1 AUX_OUT Options..............................................................................................................................39
5.3 AUDIO SAMPLING RATE SUPPORT (FIXED, VARIABLE, AND DOUBLE) .........................................................39
5.4 MULTICHANNEL AUDIO................................................................................................................................40
5.4.1 Primary Codec Multichannel Audio ....................................................................................................40
5.4.2 Secondary Codec Multichannel Audio.................................................................................................40
5.4.2.1 Default Slot to DAC Mappings for Secondary Audio Codecs .........................................................................41
5.4.2.2 DAC Management across Multiple Audio Codecs .......................................................................................... 41
5.4.2.3 Volume Control across Multiple Audio Codecs............................................................................................... 42
5.4.2.4 Playback Synchronization across Multiple Audio Codecs ............................................................................... 42
5.5 AC ‘97 ANALOG MIXER ...............................................................................................................................42
5.5.1 Analog Mixer Output ...........................................................................................................................43
5.5.2 Analog Mixer Input..............................................................................................................................44
5.5.3 Analog Mixer Feature Detection .........................................................................................................44
5.5.3.1 Minimum Analog Mixer Feature Set ............................................................................................................... 44
5.5.3.2 Analog Mixer Cost-Reduction ......................................................................................................................... 44
5.5.3.3 Original Analog Mixer Options ....................................................................................................................... 44
5.6 SLOT ASSIGNMENTS FOR AUDIO...................................................................................................................45
5.7 BASELINE AUDIO REGISTER SET ..................................................................................................................46
5.7.1 Reset Register (Index 00h)...................................................................................................................48
5.7.2 Play Master Volume Registers (Index 02h, 04h and 06h)....................................................................49
5.7.3 Master Tone Control Registers (Index 08h) ........................................................................................50
5.7.4 PC Beep Register (Index 0Ah) .............................................................................................................51
5.7.5 Analog Mixer Input Gain Registers (Index 0Ch - 18h)........................................................................51
5.7.6 Record Select Control Register (Index 1Ah)........................................................................................52
5.7.7 Record Gain Registers (Index 1Ch and 1Eh).......................................................................................53
5.7.8 General Purpose Register (Index 20h) ................................................................................................53
5.7.9 3D Control Register (Index 22h) .........................................................................................................54
5.7.10 Audio Interrupt and Paging Mechanism (Index 24h) ..........................................................................54
5.7.11 Powerdown Control/Status Register (Index 26h) ................................................................................56