HL7692 voice call - Error 288

IoT Modules Legacy HL Series
1

I’m trying to make a voice call with the HL7692, but the module answer “NO CARRIER”.

  • CEER = “CC setup error”, 288, “MM noservice” but I do not understand those errors.

  • CREG = 0,1 and CPAS = 0

The same software works with the HL8518.

Anyone has a clue on how to make a voice call with this module?

2

@PAT

Have you restricted the unit to LTE? VoLTE is not supported on this module, it should fall back to 2G if it is enabled and present.

Regards

Matt

3

Thank you for your reply!

KSRAT is set to 9 (Search for LTE first then GSM)

I tested to set to “GSM only” (COPS = 2 -> KSRAT = 1 -> COPS = 0), but I wasn’t able to get connected.

Do I understand correctly that a voice call is only possible over 2G?

And I’m perhaps not covered with a 2G signal?

4

@PAT

For this module yes, voice is only possible over 2G, VoLTE was not really around when this module was developed (about 5 years ago) and its a major feature addition that the chipset never benefited from (the chipset vendor needs to implement it. It should in theory fall back to 2G for both an incoming and outgoing call call but if you cannot see 2G then obviously it cannot fallback to it.

You can check to see if KSRAT is 9 by sending at+cops=? which will ask the unit what networks it can see.

Regards

Matt

5

Effectively, the operator I was using only have an AcT = 7.

I try with another SIM card of an operator with AcT = 7 and = 0, and it works.