During active call session when hanging up the active call though AT Command "ATH". We are getting the response "Ok" but after that, other AT Commands not get any responses. Like AT+CSQ, AT+CREG, AT+SMONI, or for simple "AT" COmm | Thales IoT Developer Community
August 10, 2020 - 8:59am, 2492 views
Hello All,
we are facing issue in the GSM Modem side during voice calls, below are our observations.
Issue: - During active call session when hanging up the active call though AT Command "ATH".
We are getting the response "Ok" but after that, other AT Commands not get any responses.
Like AT+CSQ, AT+CREG, AT+SMONI, or for simple "AT" COmmand also not receiving any responses.
A. Observation 1 :
1. GPRS session(Packet Transmission and reception) was not active after the GSM power-on.
2. Voice Call Session(Incoming call received /outgoing call dialed ) started and call status is " ACTIVE ".
3. And requested for the Call hang up the session through "ATH" Command.
4. "ATH" Command receive "OK" Response
5. All other AT Commands also execute properly with the expected response.
B. Observation 2:
Test Log files :
1. GPRS Session was active after the power-on (Able to see the packet transmission and reception ) .
2. Voice Call Session(Incoming call received /outgoing call dialed ) started and call status is " ACTIVE ".
3. And requested for the active call hang up the session through "ATH" Command
4. "ATH" Command receive "OK" Response
5. But after this, other AT Commands do not get any response.
GSM BGS5 Module Details :
- Manufacturer: Cinterion
- Device MOdule: BGS5
- Firmware Version: REVISION 01.100
- Application Revision Number: A-REVISION 00.001.36
Please help.
Thanks
Hello,
I've learnt that this isse was already reported to customer support SalesForce system and is processed. They discovered that such a situation may happen if hardware flow control is not used. In release 1 firmware hardware flow control is the only option - it is not possible to change to other settings (command returns OK). I also tried and probably was able to reproduce this. When this happened and I enabled HW flow cotrol in my terminal the communication started working again. Maybe you could try connecting the module's RTS with CTS if your hardware. I didn't test it but maybe it could help. There is also firmware revision 2 available for this module and it works on the same hardware (as it is already a new hardware). In this firmware it is possible to change HW flow control settings. I upgraded my module and wasn't able to reproduce this issue then. Maybe this could be a solution for you. I think that some tests would be necessary on your side to confirm this.
Anyway I think that this should be further processed via SalesForce.
Best regards,
Bartłomiej