Advanced Information

WM9708

WOLFSON MICROELECTRONICS LTD

AI Rev 2.0 April 2001

21

SR2 TO SR0

RIGHT RECORD SOURCE

SL2 TO SL0

LEFT RECORD SOURCE

0

Mic

0

Mic

1

CD in (R)

1

CD in (L)

2

Not supported

2

Not supported

3

Not supported

3

Not supported

4

Line in (R)

4

Line in (L)

5

Stereo mix (R)

5

Stereo mix (L)

6

Mono mix

6

Mono mix

7

Phone

7

Phone

Table 7 Record Select Register Function

RECORD GAIN REGISTERS (INDEX 1Ch)

1Ch is for the stereo input. Each step corresponds to 1.5dB. 22.5dB corresponds to 0F0Fh. The MSB

of the register is the mute bit. When this bit is set to 1, the level for that channel(s) is set at -

The default value is 8000h, which corresponds to 0dB gain with mute on.

MUTE

GX3...GX0

FUNCTION

0

1111

+22.5dB gain

0

0000

0dB gain

1

xxxxx

-

Table 8 Record Gain Register Function

GENERAL PURPOSE REGISTER (INDEX 20h)

This register is used to control several miscellaneous functions of the WM9708.

Below is a summary of each bit and its function. Only the MIX, MS and LPBK bits are supported by

the WM9708. The MS bit controls the Mic selector. The LPBK bit enables loopback of the ADC

output to the DAC input without involving the AC-link, allowing for full system performance

measurements. The function default value is 8000h which is all off.

BIT

FUNCTION

WM9708

SUPPORT

POP

PCM out path and mute

Yes

ST

Simulated stereo enhancement, on/off 1 = on

No

3D

3D stereo enhancement on/off, 1 = on

No

LD

Loudness (bass boost) on/off, 1 = on

No

LLBK

Local loop back - for modem, line codec

No

RLBK

Remote loop back - for modem, line codec

No

MIX

Mono output select 0 = Mix, 1 = Mic

Yes

MS

Mic select 0 = Mic1, 1 = Mic2

Yes

LPBK

ADC/DAC loopback mode

Yes

Table 9 General Purpose Register Function