AD1980 Analog Devices, AD1980 Datasheet - Page 14

• Manufacturer Part Number: AD1980
• Description: AD1980 AC'97 SoundMAX® Codec W/spdif W/eq
• Manufacturer: Analog Devices

AD1980
*For AC ’97 compatibility, Bit D7 is available only by setting the MSPLT bit, Register 76h. The MSPLT bit enables separate mute bits for the left and right channels.
Note that depending on the state of the AC97NC bit in Register 76h, this register has the following additional functionality:
ROV[4:0]
RM
LOV[4:0]
OM
Reg. 76h
MSPLT* D15 WRITE READBACK Function
0
0
0
0
1
1
1
*For AC ’97 compatibility, Bit D7 is only available by setting the MSPLT bit, Register 76h. The MSPLT bit enables separate mute bits for the left and right channels.
x in the above table is “don’t care.”
All registers not shown and bits containing an X are assumed to be reserved.
Refer to Table V for examples. Used to select the record source, independently for the right and left channels. For single MIC recording, see MS bit (Register 20h) for
MIC1 and MIC2 input selection.
For dual MIC recording, see 2CMIC bit (Register 76h) to enable simultaneous recording into the left and the right channels.
The default value is 0000h, which corresponds to MIC input for both channels.
RS [2:0]
LS [2:0]
Reg
No. Name
18h PCM Out Volume OM X
If MSPLT is not set, Bit D7 has no effect. All registers not shown and bits containing an X are assumed to be reserved. Refer to Table IV for examples.
For AC87NC = 0, the register also controls the Surround, Center, and LFE DAC Gain/Attenuators.
For AC97NC = 1, the register controls the PCM Out Volume only.
Reg
No. Name
1Ah Record Select
If MSPLT is not set, RM Bit has no effect.
0
0
0
1
0
1
1
Right PCM Out Volume. Allows setting the PCM right channel attenuator in 32 volume levels. The LSB represents
1.5 dB, and the gain range is +12 dB to –34.5 dB. The default value is 0 dB, mute enabled.
Right Channel Mute. Once enabled by the MSPLT bit in Register 76h, this bit mutes the right channel separately
from the AVM bit. Otherwise, this bit will always read “0” and will have no affect when set to “1.”
Left PCM Out Volume. Allows setting the PCM left channel attenuator in 32 volume levels. The LSB represents
1.5 dB, and the range is +12 dB to –34.5 dB. The default value is 0 dB, mute enabled.
PCM Out Volume Mute. When this bit is set to “1,” both the left and the right channels are muted, unless the
MSPLT bit in Register 76h is set to “1,” in which case this mute bit will affect only the left channel.
Right Record Select
Left Record Select
0 0000
0 1000
1 1111
x xxxx
1 1111
x xxxx
x xxxx
D15
X
D15 D14 D13 D12
Left Channel Volume D[12:8]
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
X
D13
X
LOV4 LOV3 LOV2 LOV1 LOV0 OMRM* X
D12
X
Line-In (10h), CD (12h), AUX (16h) and PCM-Out (18h)
Record Select Control Register (Index 1Ah)
D11
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
PCM-Out Volume Register (Index 18h)
D11
X
D10
D10
LS2
D9
D9
LS1
–14–
D8
D8
LS0
Control Bits
D7* WRITE
x
x
x
x
1
0
D7
D7
X
0 0000
0 1000
1 1111
x xxxx
x xxxx
1 1111
x xxxx
D6
X
D6 D5 D4
Right Channel Volume D[4:0]
D5
X
X
READBACK Function
0 0000
0 1000
1 1111
x xxxx
x xxxx
1 1111
x xxxx
ROV4
D4
X
D3
ROV3
D3
X
D2
RS2
D2
ROV2 ROV1 ROV0 8808h
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
D0
RS0
D0
REV. 0
Default
Default
0000h