What does the AT+CFUN command actually do?

Hey, I have an EM160R-GL, the manual says CFUN modes mean:
0 Minimum functionality
1 Full functionality
4 Disable both transmitting and receiving RF signals

0 Do not reset the UE before setting it to power level
1 Reset the UE before setting it to power level.

My questions are:

  1. I understand that mode fun = 4 means flights mode, but what does fun = 0 actually do?
  2. If I choose to reset the module via rst = 1, is that different from just doing AT+QPOWD, or is that completely the same?


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Cfun0 disables the RF component and transceiver unit,while CFUN1 does the opposite
AT+QPOWD is similar to cfun0

I suppose AT+QPOWD is a more proper way to shut down the module. It will detach the module from existing connections (deactivate PDP, de-register from network, etc) before powering down.

yes,you are right;Or you can just power off

Oh yes. Using the powerkey pin to power off is equivalent to AT+QPOWD.

yes,you are right again

@hobby_a @herbert.pan-Q Thank you for the reply, so if I change the device IMEI with AT command, is it enough to use AT+CFUN=0 and then AT+CFUN=1 for it to take effect? or do I need a full reboot?

yes,you can execute AT+CFUN=0/1 to take effect

@herbert.pan-Q That is great to hear, will AT+CFUN=4 and AT+CFUN=1 also make it take effect?

I suggest you try debugging

On other modules from Quectel there’s the command AT+CFUN=1,1 (not sure about this one)
That “saves” and reboots the module.

The big difference between the AT+CFUN=0 state and AT+QPOWD state is that in the QPOWD one the module is completely off, including the AT interface.
In AT+CFUN=0 you still can communicate with the module.