CS4235 Datasheet, PDF (36/94 Pages) Cirrus Logic – CrystalClear Low Cost ISA Audio System

CS4235
CrystalClear ^TM Low Cost ISA Audio System
Right DAC1 Volume (I7)
Default = 10000111
D7 D6 D5 D4 D3 D2 D1 D0
RD1OM res RD1A5 RD1A4 RD1A3 RD1A2 RD1A1 RD1A0
RD1A5-RD1A0 Right DAC1 Attenuation. The least
significant bit represents -1.5 dB,
with 000000 = 0 dB. The total range
is 0 to -94.5 dB. See Table 6.
RD1OM
Right DAC1 Mute. When set, the
right DAC1 to the output mixer is
muted.
Fs and Playback Data Format (I8)
Default = 00000000
D7 D6 D5 D4
rbc 16B rbc S/M
D3 D2 D1 D0
CFS2 CFS1 CFS0 C2SL
C2SL
Clock 2 Source Select: This bit selects
the clock base used for the audio
sample rates for both capture and
playback. Note that this bit can be
disabled by setting SRE in I22 or by
setting IFSE in X11.
CAUTION: C2SL can only be
changed while MCE (R0) is set.
CFS2-CFS0
Clock Frequency Divide Select: These
bits select the audio sample fre-
quency for both capture and
playback. The actual audio sample
frequency depends on which clock
base (C2SL) is selected. Note that
these bits can be disabled by setting
SRE in I22 or IFSE in X11.
CAUTION: CFS2-CFS0 can only be
changed while MCE (R0) is set.
DIVIDE
0 - 3072
1 - 1536
2 - 896
3 - 768
4 - 448
5 - 384
6 - 512
7 - 2560
C2SL = 0
8.0 kHz
16.0 kHz
27.42 kHz
32.0 kHz
N/A
N/A
48.0 kHz
9.6 kHz
C2SL = 1
5.51 kHz
11.025 kHz
18.9 kHz
22.05 kHz
37.8 kHz
44.1 kHz
33.075 kHz
6.62 kHz
S/M
Stereo/Mono Select: This bit deter-
mines how the audio data streams
are formatted. Selecting stereo will
result in alternating samples repre-
senting left and right audio channels.
Mono playback plays the same
audio sample on both channels.
Mono capture only captures data
from the left channel. In MODE 1,
this bit is used for both playback and
capture. In MODEs 2 and 3, this bit
is only used for playback, and the
capture format is independently se-
lected via I28. MCE (R0) or PMCE
(I16) must be set to modify S/M.
See Changing Audio Data Formats
section for more details.
0 - Mono
1 - Stereo
16B
selects between 8-bit unsigned and
16-bit signed data for playback. The
capture format is independently se-
lected via register I28. MCE (R0) or
PMCE (I16) must be set to modify
the upper four bits of this register.
See Changing Audio Data Formats
section for more details.
0 - 8-bit unsigned data
1 - 16-bit signed data
Interface Configuration (I9)
Default = 00x00100
D7 D6 D5 D4 D3 D2 D1 D0
CPIO PPIO res CAL1 CAL0 SDC CEN PEN
PEN
Playback Enable. This bit enables
playback. The WSS Codec will
generate a DRQ and respond to
DACK signal when this bit is en-
abled and PPIO=0. If PPIO=1, PEN
enables PIO playback mode. PEN
may be set and reset without setting
the MCE bit.
0 - Playback Disabled (playback DRQ
and PIO inactive)
1 - Playback Enabled
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DS252PP2