Baseband Processor For Mixed Mode Land Mobile Radio
CMX880
1.5.1.5
Configuration Options
The CMX880 is designed to be extremely versatile, with extensive control of the configuration of signal/data
paths is available to the host µC.
Following a reset command, the device is placed into power-save mode, with only the clock/xtal circuit and the
“C-BUS” interface active. The various functional blocks that can be individually placed into power save/standby
modes are shown in Figure 18. Valid receive and transmit signal/data path configurations that can be selected
are shown in Table 15. The options for configuring signal paths, block power-save and gains are shown in Table
16.
1
4
10
ADC
2
3
‘’C-BUS’’
and
Fast Serial
Bus
Signal
Processing
Block
8
9
5
6
7
DAC 1
DAC 2
Interface
1
2
3
4
5
Mic 1 input amp
Mic 2 input amp
FM discriminator input amp
Sigma Delta ADC
6
7
8
9
Mod 1 output amp
Mod 2 output amp
Sigma Delta DAC 1
Sigma Delta DAC 2
Signal Processing block
Audio output amp
10
Figure 18 Power-Save Blocks
Table 15 Receive and Transmit Path Configurations.
Receive Paths
From
To
From
To
FM_DISC ® “C-BUS”
FM_DISC ® FSB
FM_DISC ® Internal
OFF
“C-BUS” ® AUDIO
FSB ® AUDIO
Internal ® AUDIO
OFF
Transmit Paths
To From
From
To
MIC_1/2 ® “C-BUS”
MIC_1/2 ® FSB
MIC_1/2 ® Internal
OFF
“C-BUS” ® MOD_1/2
FSB ® MOD_1/2
Internal ® MOD_1/2
OFF
ã 2001 Consumer Microcircuits Limited
37
D/880/1
CMLMICRO [ CML MICROCIRCUITS ]
