82C931 Datasheet, PDF (52/64 Pages) List of Unclassifed Manufacturers – Plug and Play Integrated Audio Controller

82C931
Table 5-11 Expanded Mode CIR (cont.)
7
6
5
4
3
2
CIR22
Mute:
0 = Disable
1 = Enable
Reserved
00000 = 0
00001 = –3
00010 = –6
00011 = –9
00100 = –12
00101 = –15
00110 = –18
00111 = –21
OUTL Output Control Register
Gain select for OUTL (dB):
01000 = –24
01001 = –27
01010 = –30
01011 = –33
01100 = –36
01101 = –39
01110 = –42
01111 = –45
10000 = –48
10001 = –51
10010 = –54
10011 = –57
10100 = –60
10101 = –63
10110 = –66
10111 = –69
CIR23
Mute:
0 = Disable
1 = Enable
Reserved
OUTR Output Control Register
Gain select for OUTR (dB):
Refer to CIR22[5:1] for decode.
CIR24-CIR27
Reserved
1
11000 = –72
11001 = –75
11010 = –78
11011 = –81
11100 = –84
11101 = –87
11110 = –90
11111 = –93
0
Default = 80h
Reserved
Default = 80h
Reserved
Default = 00h
CIR28
Capture Data Format
Default = 00h
Audio data format - linear PCM or companded
for all input and output data
(used in conjunction with bit 5):⁽¹⁾
000 = Linear, 8-bit unsigned
001 = µ-law, 8-bit companded
010 = Linear, 16-bit two’s complement, Little Endian
011 = A-Law, 8-bit companded
100 = Reserved
101 = ADPCM, 4-bit, IMA compatible
110 = Linear, 16-bit two’s complement, Big Endian
111 = Reserved
Stereo/mono:⁽²⁾
0 = Mono
1 = Stereo
Reserved
Note: Bit 7 is not available in Mode 1 (forced to 0).
(1) SB/WSS mode switch: In Sound Blaster mode, the software driver should set CDF to 8 bit PCM mode (R8: FM1,FM-,C_L).
(2) Selecting stereo results with alternating samples representing left and right audio channels. Mono playback plays the same audio sample
on both channels. Mono capture only captures data from the left audio channel.
Note: The contents of this register can only be changed if the mode change bit (WSBase+04h[6]) is enabled (set to 1). Writes to this register
without the mode change bit enabled will have no affect.
CIR29
Reserved
Default = 00h
CIR30
Capture Upper Base Count
Default = 00h
Upper Base Count:
This byte is the upper byte of the base count register containing the eight most significant bits of the 16-bit base register.
Reads from this register return the same value which was written.
CIR31
Capture Lower Base Count
Default = 00h
Upper Base Count:
This byte is the lower byte of the base count register containing the eight most significant bits of the 16-bit base register.
Reads from this register return the same value which was written.
OPTi
®
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Revision: 2.1