nRF9160 running Serial Lte Modem with External MCU - how to control sleep and active modes

[SilasV]

Hi 

I have my custom board with nRF9160 module running Serial Lte Modem application, and an external MCU talks to nRF9160 over UART and access using AT commands. The custom board works fine as expected using the AT commands when using over PC serial port. .

Now when running with external MCU, I would like to put nRF9160 to sleep when not using, and wake up as per requirement.  What is the best approach using AT commands? Can someone help? may be provide sample commands. 

Thanks 

[Heidi]

Hi! Sorry about the late reply, I've been on vacation. 

1. If you can't wake it up when in Idle mode by sending commands, that goes against what is documented. I'll look into that.

2. The application and the modem runs asynchronously, so even if the application is in Idle mode, the modem can still handle an LTE connection and will not detach from the network.

3. PSM mode is a great way of decreasing the application's current consumption. You can use the AT command +CPSMS to enable and disable PSM.

[SilasV]

hi 

Thanks for the information!

I think instead of waiting on how to wake up nRF9160 just from sending serial commands, I would go for a dedicated pin from external MCU to nRF9160. I would go for the next version of my custom board which will take care of this. 

Thanks