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WM8581
w
PP Rev 1.0 March 2006
31
DAC OUTPUT CONTROL
The DAC output control word determines how the left and right inputs to the audio interface are
applied to the left and right DACs:
REGISTER ADDRESS
BIT
LABEL
DEFAULT
DESCRIPTION
PL[3:0]
Left O/P
Right O/P
0000 Mute Mute
0001 Left Mute
0010 Right Mute
0011 (L+R)/2 Mute
0100 Mute Left
0101 Left Left
0110 Right Left
0111 (L+R)/2 Left
1000 Mute Right
1001 Left Right
1010 Right Right
1011 (L+R)/2 Right
1100 Mute (L+R)/2
1101 Left (L+R)/2
1110 Right (L+R)/2
R16
DAC CONTROL 2
10h
3:0 PL[3:0]
1001
1111 (L+R)/2 (L+R)/2
Table 18 DAC Attenuation Register (PL)
ZERO FLAG OUTPUT
Each DAC channel has a “zero detect circuit” which detects when 1024 consecutive zero samples
have been input. Should both channels of a DAC indicate a zero-detect (or if either DACPD or
DMUTE is set for that DAC), then the Zero Flag for that DAC is asserted. The DZFM register bits
determine which Zero Flag is visible on the MUTE and GPO pins.
REGISTER ADDRESS
BIT
LABEL
DEFAULT
DESCRIPTION
R16
DAC CONTROL 2
10h
6:4
DZFM[2:0] 000 Selects the source for ZFLAG
000 - All DACs Zero Flag
001 - DAC1 Zero Flag
010 - DAC2 Zero Flag
011 - DAC3 Zero Flag
100 - DAC4 Zero Flag
101 - ZFLAG = 0
110 - ZFLAG = 0
111 - ZFLAG = 0
Table 19 DZFM Register