WM8721

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WOLFSON MICROELECTRONICS LTD

PP Rev 1.3 November 2000

27

REGISTER MAP

The complete register map is shown in Table 19. The detailed description can be found in the

relevant text of the device description. There are 8 registers with 9 bits per register. These can be

controlled using either the 2 wire or 3 wire MPU interface.

REGISTER

ADDRESS

BIT

LABEL

DEFAULT

DESCRIPTION

6:0

LHPVOL

[6:0]

1111001

( 0dB )

Left Channel Headphone Output

Volume Control

1111111 = +6dB

. . 1dB steps down to

0110000 = -73dB

0000000 to 0101111 = MUTE

7

LZCEN

1

Left Channel Zero Cross detect

Enable

1 = Enable

0 = Disable

0000010

Left Headphone

Out

8

LRHPBOTH

0

Left to Right Channel Headphone

Volume, Mute and Zero Cross Data

Load Control

1 = Enable Simultaneous Load of

LHPVOL[7:0] and LZCEN to

RHPVOL[7:0] and RZCEN

0 = Disable Simultaneous Load

6:0

RHPVOL

[7:0]

1111001

( 0dB )

Right Channel Headphone Output

Volume Control

1111111 = +6dB

. . 1dB steps down to

0110000 = -73dB

0000000 to 0101111 = MUTE

7

RZCEN

1

Right Channel Zero Cross detect

Enable

1 = Enable

0 = Disable

0000011

Right

Headphone Out

8

RLHPBOTH

0

Right to Left Channel Headphone

Volume, Mute and Zero Cross Data

Load Control

1 = Enable Simultaneous Load of

RHPVOL[7:0] and RZCEN to

LHPVOL[7:0] and LZCEN

0 = Disable Simultaneous Load

0000100

Audio Path

Control

4

DACSEL

0

DAC Select (Analogue)

1 = Select DAC

0 = Don’t select DAC

2:1

DEEMP[1:0]

00

De-emphasis Control (Digital)

11 = 48KHz

10 = 44.1KHz

01 = 32KHz

00 = Disable

0000101

Digital Audio

Path Control

3

DACMU

1

DAC Soft Mute Control (Digital)

1 = Enable soft mute

0 = Disable soft mute