Hi everybody,
I’m developing over RAK13101 (MC20) together with the RAK4631 (NRF52).
Using the sketch of “Unvarnished_Transmission.ino” the MC20 answers correctly to different commands like ATI, AT+QGNSSC=1, AT+COPS=?, etc.
But the problem is that when i try the AT+COPS=1,0,“Network name” the MC20 turns off unexpectedly and stops responding.
I’m currently giving power through the Solar panel connector of the RAK19001 base board with the RAK19004 Green Power Module and the USB cable.
I change the connection of the RAK19004 to the no rechargeable battery connector and it stop turning off but it still can´t connect to the detected network, found by the AT+COPS=? command.
It returns an unknown error
If your power source is stable now and the module returns unknown error but continue to operate, maybe it is good to validate the SIM and network. You can try to use the sim card to your phone and see if signal is good and works ok.
It can also be related to GSM/GPRS network coverage related since some areas have shutdown the operation of 2G based cellular network.
You can also try to set AT+CMEE=1 or AT+CMEE=2 to get more error details from the module.
I check the GSM/GPRS network coverage and it should be still working where I am so i think my problem will be either the SIM or the power source since in the datasheet of the RAK19004 Green Power Module, it said that it can give up to 1 Amp and the MC20 consumption can get up to 1.6 Amp.
I also just realize that i am using an LTE 4G SIM card, does somebody know if the module is compatible with the SIM?
I know that where i am testing the module, we still have 2G network and that the LTE SIM supports 2G network fallback.
I am using 4G and 5G advertised SIM for my RAK13101 and it works ok. We still have large 2G network here in PH but recently mandated transition to full 4G and 5G due to vulnerability issues. Is your power source well stablished now? Are there any specific error when you enabled CMEE?
No specific error, still giving unknown even with CMEE enable.
Even with a 5 V 3 Amp source, when using the AT+COPS to try to connect to an operator, manually or automatically, it can never seem to finish the connection and returns the unknown error after a couple of minutes.
I check the signal strength in the module, it was okay but the cellular network provider warn me that it may be incompatible with older modem, i guess that must be the problem.
Just in case you may get another idea i can try, i did the following commands:
AT+CREG? and AT+CGREG? → Answer: (0,2) or (0,0)
Even it i try AT+COPS=1,1,“Short name” or AT+COPS=1,2,“Identification number” with either of the detected operators the result will be the same answer