nRF9160: AT monitor¶
The sample supports the following development kit:
The sample is configured to compile and run as a non-secure application on nRF91’s Cortex-M33. Therefore, it automatically includes the Secure Partition Manager that prepares the required peripherals to be available for the application.
You can also configure it to use TF-M instead of Secure Partition Manager.
The sample defines two AT monitors, one for network status notifications (
+CEREG) and one for received signal quality parameters notifications (
+CESQ) through the
The sample then subscribes to both notifications and switches the modem to function mode one to register to the network.
While the device is registering to the network, the sample uses one of the AT monitors to determine if the registration is complete and monitors the signal quality using the other monitor.
Once the device registers with the network, the sample reads the modem PSM mode status, enables it, and reads the PSM mode status again.
This sample can be found under
samples/nrf9160/at_monitor in the nRF Connect SDK folder structure.
The sample is built as a non-secure firmware image for the nrf9160dk_nrf9160ns build target. Because of this, it automatically includes the Secure Partition Manager. You can also configure it to use TF-M instead of SPM.
See Building and programming an application for information about how to build and program the application.
After programming the sample to your development kit, test it by performing the following steps:
Connect the kit to the computer using a USB cable. The kit is assigned a COM port (Windows) or ttyACM device (Linux), which is visible in the Device Manager.
Connect to the kit with a terminal emulator (for example, PuTTY). See How to connect with PuTTY for the required settings.
Power on or reset your nRF9160 DK.
Observe that the sample starts and connects to the LTE network, while displaying both the network registration status and signal quality during the process.
Observe that the sample displays the PSM status twice on the terminal, once when it is disabled, and once when it is enabled.
Observe that the sample completes with a message on the terminal.
The sample shows the following output:
AT Monitor sample started Subscribing to notifications Connecting to network Resuming link quality monitor for AT notifications Waiting for network Link quality: -61 dBm Network registration status: searching Link quality: -59 dBm Network registration status: home Network connection ready Pausing link quality monitor for AT notifications Reading PSM info... PSM: disabled Enabling PSM Reading PSM info... PSM: enabled Periodic TAU string: 00000110 Active time string: 00100001 Modem response: +CEREG: 1,1 OK Shutting down modem Network registration status: no network Bye