in GSM MODULE, How can i calculate the call duration ?

[eng_ahmed22]

3gpp call duration

Salam All
I have a GSM Module.
I connect it to the serila port of a PC
i can make a Call using ATDxxxxxxxxxxx;
and hang up by ATH

the question is: How can i calculate the call duration????
i want to know the call timer during the call progress
how can i do this?????????????????????????????
best regards
Ahmed

 

[yager]

In fact, it is depended on the ability of your GSM module.
Here are 3 methods to try to solve your question, FYR.
1. to monitor the responses/result codes from the GSM module
also depends on E,Q,V,X commands
2. to monitor the RLSD/CD (Received Line Signal Detector/Carrier Detect)
also depends on '&C','&D' CD/DTR behavior commands
3. to request the call meter via GSM AT commands
+CAOC/+CACM for current/accumulated call meter
For more details, to read valued documents (07.07) from ETSI or 3GPP.