REV. 0

AD1981A

–21–

REGM0

Master Codec Register Mask

REGM1

Slave 1 Codec Register Mask

REGM2

Slave 2 Codec Register Mask

SLOT16

Enable 16-Bit Slot Mode.

SLOT16 makes all AC link slots 16 bits in length, formatted into 16 slots.

This is a preferred mode for DSP serial port interfacing.

Miscellaneous Control Bits (Index 76h)

Reg Num Name

D15

D14

D13

D12 D11 D10

D9

D8 D7

D6

D5

D4

D3

D2

D1

D0

Default

76h

Misc Control Bits DACZ

X MSPLT

X DAM

X FMXE X

X MADPD X MADST VREFH VREFD MBG1 MBG0 0000h

MBG[1:0]

MIC Boost Gain Change Register:

These two bits allow changing the MIC preamp gain from the nominal 20 dB gain.

Note: This gain setting only takes effect while Bit D6 (M20) on the MIC Volume Register (0Eh) is set to 1. Otherwise

the MIC boost block has a gain of 0 dB.

00 = 20 dB Gain (Reset Default)

01 = 10 dB Gain

10 = 30 dB Gain

11 = Reserved

VREFD

Note that this bit overrides the VREFH bit selection (see below).

VREFH

MADST

Mixer ADC Status Bit: Indicates status of mixer digitizing ADC (L/R channels)

0 = Mixer ADC Not Ready

1 = Mixer ADC Is Ready

MADPD

Mixer ADC Power-Down: Controls power-down for mixer digitizing ADC.

0 = Mixer ADC Is Powered-On (Default)

1 = Mixer ADC Is Powered-Down

FMXE

Front DAC into Mixer Enable: Controls the Front (main) DAC to Mixer mute switches.

0 = Front DAC Outputs Are Allowed to Sum into the Mixer (Reset Default)

1 = Front DAC Outputs Are Muted into the Mixer (Blocked)

DAM

Digital Audio Mode: PCM DAC outputs bypass the analog mixer and are sent directly to the Codec output.

MSPLT

Mute Split: Allows separate mute control bits for master, Headphone, LINE_IN, CD, AUX, and PCM volume control

Registers as well as Record Gain Register and mixer ADC volume.

0 = Both Left and Right Channel Mutes Are Controlled by Bit 15 in the Respective Registers (Reset Default)

1 = Bit 15 Affects Only the Left Channel Mute and Bit 7 Affects Only the Right Channel Mute

DACZ

DAC Zero-Fill: (versus repeat) if DAC is starved for data.

0 = When DAC Is Filled with Repeat Data

1 = When DAC Is Filled with Zeros (Reset Default)

Vendor ID Registers (Index 7Ch)

Reg Num Name

D15 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 Default

7Ch

Vendor ID1

F 7

F 6

F 5

F 4

F 3

F 2

F 1 F 0 S7

S6

S5

S4

S3

S2

S1

S0

4144h

S[7:0] This register is ASCII encoded to ‘A’

F[7:0] This register is ASCII encoded to ‘D’