cs4237b Cirrus Logic, Inc., cs4237b Datasheet - Page 39

• Manufacturer Part Number: cs4237b
• Description: Crystalclear Advanced Audio System With 3d Sound
• Manufacturer: Cirrus Logic, Inc.

C/L, FMT1, and FMT0 bits set the audio data format
† FMT1 is not available in MODE 1 (forced to 0).
Interface Configuration (I9)
Default = 00x01000
PEN
DS213PP4
FMT1
CPIO
D7
D7
0
0
0
0
1
1
1
1
†
PPIO
D6
FMT0
D6
0
0
1
1
0
0
1
1
D5
res
0 - Mono
1 - Stereo
as shown below. In MODE 1, FMT1,
which is forced low, FMT0, and C/L
are used for both playback and cap-
ture. In MODEs 2 and 3, these bits
are only used for playback, and 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.
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
1 - Playback Enabled
C/L
D5
0
1
0
1
0
1
0
1
and PIO inactive)
CAL1
D4
Linear, 8-bit unsigned
Linear, 16-bit two’s
complement, Little Endian
A-Law, 8-bit companded
RESERVED
ADPCM, 4-bit, IMA compatible
Linear, 16-bit two’s
complement, Big Endian
RESERVED
-Law, 8-bit companded
Audio Data Format
CAL0
D3
SDC
D2
CEN
D1
PEN
D0
CEN
SDC
CAL1,0
PPIO
CPIO
Capture Enabled. This bit enables the
capture of data. The WSS Codec
will generate a DRQ and respond to
DACK signal when CEN is enabled
and CPIO=0. If CPIO=1, CEN en-
ables PIO capture mode. CEN may
be set and reset without setting the
MCE bit.
0 - Capture Disabled (capture DRQ
1 - Capture Enabled
Single DMA Channel: This bit will force
BOTH capture and playback DMA re-
quests to occur on the Playback
DMA channel. This bit forces the
WSS Codec to use one DMA chan-
nel. Should both capture and
playback be enabled in this mode,
only the playback will occur. See the
DMA Interface section for further ex-
planation.
0 - Dual DMA channel mode
1 - Single DMA channel mode
Calibration: These bits determine
which type of calibration the WSS
Codec performs whenever the Mode
Change Enable (MCE) bit, R0,
changes from 1 to 0. The number of
sample periods required for calibra-
tion is listed in parenthesis.
0 - No calibration (0)
1 - Converter calibration (321)
2 - DAC calibration (120)
3 - Full calibration (450)
Playback PIO Enable: This bit deter-
mines whether the playback data is
transferred via DMA or PIO.
0 - DMA transfers
1 - PIO transfers
Capture PIO Enable: This bit deter-
mines whether the capture data is
transferred via DMA or PIO.
0 - DMA transfers
1 - PIO transfers
and PIO inactive)
CS4237B
39