Commands are not recorded on the SIM7080G GSM modem

I'm trying to figure out the SIM7080G module. An error occurs with some queries. To see the error code, send the command AT+CMEE = 1.

The problem is that I send this command and I get the answer OK. Next, I check if the value was written and see that it remains the same, equal to “0”.

Some commands have the same behavior. For example, with the command AT + CNMP = 13 I want to select the operating mode “GSM”, but the value remains equal to 38 - “LTE”.

But for example, with the command AT + IPR = 115200 I change the baudrate and it is correctly set.

Please tell me what could be the reason.

Thanks in advance.

A reboot probably occurred between the set command and the subsequent read command.

Commands parameters can be designed with three different behaviors:

1. Never saved after reboot
2. Always saved after reboot
3. Saved in a specific profile section (this is usually the case for ETSI standard commands)

Apparently SIM7080G module don't support profile sections. Anyway, for every command, "Parameter Saving Mode" is specified in the AT command guide.

The options are:

NO_SAVE: never saved through reboot.

AUTO_SAVE: The parameter of the current AT command is saved in NVRAM automatically, it takes effect immediately, and it won't be lost if module is rebooted.

AUTO_SAVE_REBOOT: The parameter of the current AT command is saved in NVRAM automatically, it takes effect after reboot, and it won't be lost if module is rebooted.

-: "-" this AT command doesn’t care the parameter saving mode