Production Data
WM8770
REGISTER ADDRESS
10111
BIT
LABEL
DEFAULT
DESCRIPTION
8
MS
0
Audio Interface Master/Slave
Mode select:
Interface Control
0 : Slave Mode
1: Master Mode
MASTER MODE ADCLRC/DACLRC FREQUENCY SELECT
In Master mode the WM8770 generates ADCLRC, DACLRC and BCLK. These clocks are derived
from master clock and the ratio of MCLK to ADCLRC and DACLRC are set by ADCRATE and
DACRATE.
REGISTER ADDRESS
BIT
LABEL
DEFAULT
DESCRIPTION
10111
ADCLRC and DACLRC
Frequency Select
2:0 ADCRATE[2:0]
010
Master Mode MCLK:ADCLRC
ratio select:
010: 256fs
011: 384fs
100: 512fs
101: 768fs
6:4 DACRATE[2:0]
010
Master Mode MCLK:DACLRC
ratio select:
000: 128fs
001: 192fs
010: 256fs
011: 384fs
100: 512fs
101: 768fs
ADC OVERSAMPLING RATE SELECT
For ADC operation at 96kHz it is recommended that the user set the ADCOSR bit. This changes the
ADC signal processing oversample rate to 64fs.
REGISTER ADDRESS
BIT
LABEL
DEFAULT
DESCRIPTION
ADC oversampling rate select
0: 128x oversampling
10111
3
ADCOSR
0
ADC Oversampling
Rate
1: 64x oversampling
MUTE MODES
The WM8770 has individual mutes for each of the four DAC channels. Setting MUTE for a channel
will apply a ‘soft’ mute to the input of the digital filters of the channel muted. DMUTE[0] mutes DAC
channel 1, DMUTE[1] mutes DAC channel 2, DMUTE[2] mutes DAC channel 3 & DMUTE[3] mutes
DAC channel 4.
REGISTER ADDRESS
10100
BIT
LABEL
DEFAULT
DESCRIPTION
DAC Soft Mute select
0 : Normal Operation
1: Soft mute enabled
3:0
DMUTE[3:0]
0
Mute Control
Setting the MUTEALL register bit will apply a 'soft' mute to the input of all the DAC digital filters:
REGISTER ADDRESS
10100
BIT
LABEL
DEFAULT
DESCRIPTION
Soft Mute select
4
MUTEALL
0
Mute Control
0 : Normal Operation
1: Soft mute all channels
PD Rev 4.1 June 2005
27
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WOLFSON [ WOLFSON MICROELECTRONICS PLC ]
