CS4205 Datasheet, PDF (17/80 Pages) Cirrus Logic – CrystalClear Audio Codec 97 with Portable Computing

CS4205
3.2 Digital Centric Mode
Digital centric mode is detailed in Figure 11. In this
mode, the analog sources are first mixed in the an-
alog mixer and sent to the ADCs. The ADC outputs
are then mixed with the digital sources in the digital
mixer. This allows effects processing on all sources
and supports a “what you hear is what you record”
model. The processed digital signal is sent to the
DACs, bypassing the analog mixer using DAC di-
rect mode. The ADC mux must be set to stereo mix
to support this model. Consequently, only the mix
can be captured by the host, rather than the individ-
ual sources.
3.3 Host Processing Mode
Host processing mode is detailed in Figure 12. This
mode is similar to digital centric mode, except the
output of the digital mixer is captured by the host.
Any mixing with host sources and effects process-
ing is done on the host. The processed signal is sent
to the DACs, bypassing the analog mixer using
DAC direct mode. In host processing mode, the
playback and capture paths are completely separate
inside the CS4205.
3.4 Multi-Channel Mode
Multi-channel mode is detailed in Figure 13. This
mode is an extension of any of the other three
modes, with the distinguishing feature that one or
two additional slot pairs are routed to the serial data
output ports. This allows for a complete
multi-channel solution with a single AC ’97 audio
codec and external DACs.
AC Mode
Control Bits
DACS
CAPS[1:0]
MICS
DDM
SDOS[1:0]
SPDS[1:0]
Analog Centric
Mode
1
00
0 or 1
0
10 or 11
00, 01, 10 or 11
Digital Centric
Mode
1
10
0 or 1
1
11
00, 01, 10 or 11
Host Processing
Mode
0
10
0 or 1
1
-
00 or 01
Multi-Channel
Mode
0 or 1
00,10 or 11
0 or 1
0 or 1
00
N/A
Table 1. AC Mode Control Configurations
DS489PP2
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