Cs4205, 29 special feature address register (index 6ch), 30 special feature data register (index 6eh) – Cirrus Logic CS4205 User Manual
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CS4205
DS489PP4
47
5.29
Special Feature Address Register (Index 6Ch)
A[3:0]
Special Feature Address. This register functions as an index register to select the desired func-
tionality of the Special Feature Data Register (Index 6Eh). Before using any of these indexed
registers, the correct index value must be written to bits A[3:0].
Default
0000h
5.30
Special Feature Data Register (Index 6Eh)
D[15:0]
Special Feature Data. This register is an indexed data port for the special feature registers (In-
dex 6E, Address 00h - 0Fh) which control advanced subsystems of the CS4205, such as digital
mixer settings, effects engine parameters, ZV Port control, and internal error condition signaling.
Before using any of these functions, the correct index value must be written to the Special Fea-
ture Address Register (Index 6Ch).
Default
8000h
5.31
Digital Mixer Input Volume Registers (Index 6Eh, Address 00h - 05h)
Mute
Digital Mixer Mute. Setting this bit mutes the respective input signal, both left and right inputs.
GL[5:0]
Left Volume Control. The GL[5:0] bits are used to control the digital mixer left channel input vol-
ume. Each step corresponds to 1 dB gain adjustment. The total range is 0 dB to -63 dB gain.
GR[5:0]
Right Volume Control. The GR[4:0] bits are used to control the digital mixer right channel input
volume. Each step corresponds to 1 dB gain adjustment. The total range is 0 dB to -63 dB gain.
Default
8000h. This value corresponds to 0 dB gain and Mute ‘set’.
If the digital mixer signals an overflow condition by setting the MLOF or MROF bit in the IEC Status Register (Index 6Eh,
Address 0Bh), the controller should correct the error by reducing the digital mixer input volumes in these registers. The
Digital Mixer Input Volume Registers are listed in Table 17.
D15
D14
D13
D12
D11
D10
D9
D8
D7
D6
D5
D4
D3
D2
D1
D0
0
0
0
0
0
0
0
0
0
0
0
0
A3
A2
A1
A0
D15
D14
D13
D12
D11
D10
D9
D8
D7
D6
D5
D4
D3
D2
D1
D0
D15
D14
D13
D12
D11
D10
D9
D8
D7
D6
D5
D4
D3
D2
D1
D0
D15
D14
D13
D12
D11
D10
D9
D8
D7
D6
D5
D4
D3
D2
D1
D0
Mute
0
GL5
GL4
GL3
GL2
GL1
GL0
0
0
GR5
GR4
GR3
GR2
GR1
GR0
Register Address
Function
00h
PCM Input Volume
01h
ADC Input Volume
02h
SDI1 Volume
03h
SDI2 Volume
04h
SDI3 Volume
05h
ZV Volume
Table 17. Digital Mixer Input Volume Register Index