Baseband Processor For Mixed Mode Land Mobile Radio
CMX880
tone is detected and when a present Selcall tone turns off (i.e. at the start and at the finish of each Selcall tone).
It is up to the user/host mC to turn the audio path on and off at the appropriate times. Adjustable decoder
bandwidths and threshold levels permit certainty and signal to noise performance to be traded when congestion
or range limits the system performance.
The voice signal is derived from the received input signal by the band pass filtering shown in Figure 5.
Associated Control and Status
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Reset.
Enable Selcall Tone Detection.
Set decoder bandwidth.
Set tone detection threshold level.
Interrupt masks - Tone Detected, Lost Tone.
Interrupt flag - Tone Detected, Lost Tone.
Flags set on change of associated status and interrupt issued if appropriate mask bit is set.
Interrupt status - Tone detected, Lost Tone.
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ã 2001 Consumer Microcircuits Limited
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D/880/1
CMLMICRO [ CML MICROCIRCUITS ]
