CS4231A Datasheet, PDF (59/76 Pages) List of Unclassifed Manufacturers – PARALLEL INTERFACE MULTIMEDIA AUDIO CODEC

CDB4231/4248
STEREO ANALOG OUTPUTS
The CDB4231/4248 contains one stereo analog
output labeled Ln/Hp O, Line/Headphone Out,
(Figure 5) with a maximum full-scale output of
2 V_RMS. This output provides a high-quality line
out for use with external power amps or other
equipment containing line-level inputs. It is also
designed to drive headphones directly with ex-
ceptional quality.
MONO INPUT AND OUTPUT
The CS4231 contains a MIN (mono in) pin and
a MOUT (mono out) pin that are typically
placed in between the internal PC speaker and
the beeper chip. The CDB4231 comes with a ca-
ble that should be connected between the PC
beeper chip and the SPEAKER IN header (Fig-
ure 1) on the CDB4231 board. The cable wire,
pin 1, should be placed on pin 1 of the
SPEAKER IN header and pin 1 of the beeper
header. If the PC beeps do not mix into the
codec, try reversing the beeper header connector.
This connects the beeper to the MIN pin on the
CS4231 and allows traditional PC beeps to be
mixed into the audio path.
The SPEAKER OUT header (Figure 3) should be
connected to the PC speaker. The MOUT pin on
the CS4231 is a mix of both left and right chan-
nels and has an independent software mute. The
quality of this circuit is limited to the quality of
the speaker used. Much higher fidelity can be
achieved by using a higher quality speaker.
Since the CS4248 does not have MIN and
MOUT pins, the CDB4248 board does not pro-
vide a cable, and the SPEAKER IN and SPEAKER
OUT headers are non-functional.
SERIAL AUDIO DATA PORT
The CS4231A contains a serial audio data port
that can pass audio data from the ADCs and to
the DACs across the serial port. All control data
must still be transferred via the ISA bus. The
CDB4231 supports the CS4231A by providing a
header, labeled J34, that is connected to the se-
rial audio data port on the CS4231A. The even
pins are connected to ground and the rest of the
header pins are defined as follows:
1 - not used
3 - SDOUT
5 - SDIN
7 - SCLK
9 - FSYNC
Twisted pair ribbon cable should be used when
connecting to this header. Since the CS4231 and
CS4248 do not support the serial audio data port,
these pins are non-functional on the CDB4248
and when using a CS4231.
BASE ADDRESS
The base address is set using header J18 (Fig-
ure 6) and must match the software selected base
address. The CDB4231/4248 evaluation board
uses 8 I/O addresses. The first four are used to
read the board ID of 04. Writes to the first four
addresses are ignored. The board ID is output
from the ID31 PLD and indicates that the board
is Windows Sound System, WSS, compatible
(see limitations listed in the SOFTWARE COM-
PATIBILITY section).
DS111DB7
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