CS4239 Datasheet, PDF (43/98 Pages) Cirrus Logic – CrystalClear™ Portable ISA Audio System

CS4239
CrystalClear^TM Portable ISA Audio System
Compatibility ID (I25)
Default = 00000011
D7 D6 D5 D4 D3 D2 D1 D0
V2
V1 V0 CID4 CID3 CID2 CID1 CID0
CID4-CID0
Chip Identification. Distinguishes
between this chip and previous
codec chips that support this register
set. This register is fixed to indicate
code compatibility with the CS4236.
X25 or C1 should be used to further
differentiate between parts that are
compatible with the CS4236.
All Chips:
00011 - CS4236, CS423xB, CS4239
00010 - CS4232/CS4232A
00000 - CS4231/CS4231A
V2-V0
Version number. As enhancements
are made to the part, the version
number is changed so software can
distinguish between the different ver-
sions.
000 - Compatible with the CS4236
These bits are fixed for compatibility
with the CS4236. Register X25 or
C1 may be used to differentiate be-
tween the CS4236 and newer chips.
Mono Input Control (I26)
Default = exxxeeee
D7 D6 D5 D4
MIM rbc rbc res
D3 D2 D1 D0
MIA3 MIA2 MIA1 MIA0
MIA3-MIA0
Mono Input Attenuation. When MIM
is 0, these bits set the level of MIN
summed into the mixer. These bits
are initialized through the Hardware
Configuration data, Serial Port Con-
trol byte.
0000 = 0 dB.
0001-1111 = -9 dB
MIM
Mono Input Mute. In MODE 3, MIM
mutes the MIN analog input to the
left output mixer channel. MIMR in
X4 mutes MIN analog input to the
right output mixer channel. In
MODE 2, MIM mutes both left and
right channels. The mono input pro-
vides mix for the "beeper" function in
most personal computers. This bit is
initialized through the Hardware Con-
figuration data, Serial Port Control
byte.
0 - no mute
1 - muted
Left Master Output Volume (I27)
Default = 00100011
D7 D6 D5 D4 D3 D2 D1 D0
LOM LOS1 LOS0 LOG4 LOG3 LOG2 LOG1 LOG0
When Hardware Volume is enabled, VCEN in C8 or
X24 is set, this register will change based on external
buttons.
LOG4-LOG0
Left Output, LOUT, Master Gain.
LOG0 is the least significant bit and
represents -2 dB, with 00011 = 0 dB.
The span is nominally +6 dB to
-56 dB. See Table 9.
LOS1,0
Left Output Mixer Select. These bits
select and attenuation into the left
output Master Gain stage, LOG4-0.
00 - -16 dB
01 - 0 dB
10 - -8 dB
11 - -24 dB
LOM
Left Output Mute. When set to 1,
the left output, LOUT, is muted.
DS253PP2
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