CS4237B Datasheet, PDF (62/114 Pages) Cirrus Logic – CrystalClear Advanced Audio System with 3D Sound

E²PROM Interface
CTRLbase+1, Default = 10000000
D7 D6 D5 D4 D3 D2 D1 D0
ICH ISH ADC1 ADC0 IMH DIN/ DOUT CLK
EEN
CLK
This bit is used to generate the clock
for the Plug and Play E²PROM.
EEN must be set to 1 to make this
bit operational.
DOUT
This bit is used to output serial data
to the Plug and Play E²PROM. EEN
must be set to 1 to make this bit op-
erational.
DIN/EEN
When read (DIN), this bit reflects
the XD0 pin, which should be serial
data output from the Plug and Play
E²PROM. EEN and DOUT must be
1 for this bit to function.
When written (EEN), enables the
E²PROM interface: CLK and DOUT
onto the peripheral port pins. Writing:
0 - E²PROM interface disabled
1 - E²PROM interface enabled
IMH*
Interrupt polarity - Modem. When set,
the MINT pin is an active high sig-
nal. When low, MINT is an active
low signal.
ADC1,0
These two bits are used to control
an additional A/D mux and enable
for an analog loopback path. These
two mixing paths provide Karaoke
support. These bits are provided for
backwards compatibility. New soft-
ware should use the MIC volume
control in MODE 3 registers X2/X3
to support MIC mix to the output
mixer. See Figure 6.
00 - Normal. A/D input from the input
mux.
01 - Codec Input mux is mixed into
output mixer. A/D input is from
the input mux. This facilitates the
Mic mixed to output, but only Mic
recorded.
CS4237B
10 - Codec Input mux is mixed into
output mixer. A/D input is from
line outputs. This facilitates the Mic
mixed to output, and the output
recorded by the ADCs.
11 - reserved.
Figure 6. MODE 2 Mixer Addition
ISH*
Interrupt polarity - External Synthe-
sizer. When set, the SINT pin is an
active high signal. When low, SINT
is an active low signal.
ICH*
Interrupt polarity - CDROM. When set,
the CDINT pin is an active high sig-
nal. When low, CDINT is an active
low signal.
* Note: These bits can be initialized through the
Hardware Configuration data.
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