CMX602B Consumer Microcircuits Limited, CMX602B Datasheet - Page 18

• Manufacturer Part Number: CMX602B
• Description: Calling Line Identifier Plus Call Waiting Type ii
• Manufacturer: Consumer Microcircuits Limited

Calling Line Identifier
2.
3.
 2003 CML Microsystems Plc
The IRQN output going low when in Tone Alert Detect mode indicates that a CAS has been
detected. The local handset and keypad should then be muted as required by the Bellcore
specification and the CMX602B switched to FSK Receive mode to be ready to receive the FSK
data, doing this will also clear the IRQN output.
The CMX602B’s DET output should be monitored for a period of 50ms after changing to FSK
Receive mode, before sending the ACK signal, and the transaction abandoned if the DET output
goes high during this time, which would be the case if a false CAS detect had been caused by far
end speech.
Figure 9b : Flow Chart for Off-hook Operation of CMX602B
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CMX602B
D/602B/2