Hello All,
the board I’m using has SIMPRESS line not connected to the SIM holder but always high.
If I remove SIM after network registration (GSM LED blinking, registration event received in embedded app)
in about 20 sec. GSM LED turns constant on, but AT+CREG? still reports:
+CREG: 0,1
i.e I’m still connected to the home network.
Constant GSM LED tells that the firmware knows the SIM was removed, but +CREG wont tell me about that.
Any idea how to get the info about the SIM status from the firmware?
Any SIM-related AT command would give a suitable error?
For now I’m using AT+CIMI to check if the SIM is there, but this is kind of not strait 
.
If you want it “straight”, then you really need to use the SIM presence signal - that’s what it’s there for!
Anything else is just a bodge!