AD1981B Analog Devices, AD1981B Datasheet - Page 15

• Manufacturer Part Number: AD1981B
• Description: AD1981B AC'97 SoundMAX® Codec
• Manufacturer: Analog Devices

Reg. 76h
MSPLT* D15 WRITE READBACK Function
0
0
0
0
1
1
1
*For AC ’97 compatibility, Bit D7 (RM) is available only by setting the MSPLT bit, Register 76h. The MSPLT bit enables separate mute bits for the left and right
x in the above table is a wild card and has no effect on the value.
All registers not shown and bits containing an X are assumed to be reserved. Used to select the record source independently for right and left. The default value is
0000h, which corresponds to MIC In. Refer to Table V for examples.
RS[2:0]
LS[2:0]
*For AC ’97 compatibility, Bit D7 (RM) is available only by setting the MSPLT bit, Register 76h. The MSPLT bit enables separate mute bits for the left and right
REV. A
Reg
No. Name
1Ah Record Select
Reg
No. Name
1Ch Record Gain
channels. If MSPLT is not set, RM bit has no effect.
channels. If MSPLT is not set, RM bit has no effect. All registers not shown and bits containing an X are assumed to be reserved. Refer to Table VI for examples.
0
0
0
1
0
1
1
LS [10:8]
000
001
010
011
100
101
110
111
Right Record Select
Left Record Select
0 0000
0 1000
1 1111
x xxxx
1 1111
x xxxx
x xxxx
D15
IM
D15
X
Left Channel Volume D[12:8]
D14
X
D14
X
Table IV. Volume Settings for Line-In, CD Volume, AUX, and PCM-Out
0 0000
0 1000
1 1111
x xxxx
1 1111
x xxxx
x xxxx
Left Record Source
MIC
CD_L
Muted
AUX_L
LINE_IN_L
Stereo Mix (L)
Mono Mix
PHONE_IN
D13
X
D13
X
D12
X
D12
X
Line-In (10h), CD (12h), AUX (16h), and PCM-Out (18h)
D11
LIM3
Table V. Settings for Record Select Control
Record Select Control Register (Index 1Ah)
12 dB Gain
0 dB Gain
34.5 dB Gain
– dB Gain, Muted
–34.5 dB Gain
– dB Gain,
Left Only Muted
– dB Gain, Left Muted 1
D11
X
Record Gain Register (Index 1Ch)
D10
LIM2
D10
LS2
D9
LIM1 LIM0
D9
LS1
–15–
RS [2:0]
000
001
010
011
100
101
110
111
D8
D8
LS0
Control Bits
D7* WRITE READBACK Function
x
x
x
x
1
0
D7
X
D7
RM* X
0 0000
0 1000
1 1111
x xxxx
x xxxx
1 1111
x xxxx
D6
X
D6
Right Channel Volume D[4:0]
D5
X
D5
X
0 0000
0 1000
1 1111
x xxxx
x xxxx
1 1111
x xxxx
D4
X
D4
X
Right Record Source
MIC
CD_R
Muted
AUX_R
LINE_IN_R
Stereo Mix (R)
Mono Mix
PHONE_IN
D3
RIM3 RIM2
D3
X
D2
D2
RS2
+12 dB Gain
0 dB Gain
–34.5 dB Gain
– dB Gain, Muted
– dB Gain,
Right Only Muted
–34.5 dB Gain
– dB Gain, Right Muted
D1
RS1
D1
RIM1
AD1981B
D0
RS0
D0
RIM0 8000h
Default
0000h
Default