CS4237B Datasheet, PDF (38/114 Pages) Cirrus Logic – CrystalClear Advanced Audio System with 3D Sound

CS4237B
Right DAC (PC Wave) Volume (I7)
Default = 10000000
D7 D6 D5 D4
RDOM RDG6 RDG5 RDG4
RPM res RPA5 RPA4
D3
RDG3
RPA3
D2
RDG2
RPA2
D1
RDG1
RPA1
D0
RDG0
RPA0
If both IFM (X4 or Global Config. byte) and WTEN
(C8 or Global Config. byte) are cleared, this register
is the master digital audio volume for the right chan-
nel with the following bit definitions:
See Table below.
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.
RDG6-RDG0
Right DAC Master Volume. The least
significant bit represents 1.5 dB, with
0000000 = 0 dB. The total range is
+12 to -94.5 dB. See Table 12.
RDOM
Right DAC Master Mute. When set,
the right DAC to the output mixer is
muted.
If IFM or WTEN is set, this register controls the right
channel volume for data coming from the ISA bus
only (and X15 is the right channel digital audio mas-
ter volume) with the following bit descriptions.
RPA5-RPA0
Right PC Wave 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.
res
Reserved. Must write 0. Could read
as 0 or 1.
RPM
Right PC Wave Mute. When set, the
right PCM input to the digital mixer
summer will be muted.
Fs and Playback Data Format (I8)
Default = 00000000
D7 D6 D5 D4
FMT1 FMT0 C/L S/M
D3 D2 D1 D0
CFS2 CFS1 CFS0 C2SL
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.
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.
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