AT Client¶
Overview¶
The AT Client sample demonstrates the asynchronous serial communication taking place over UART to the nRF9151 modem. It acts as a proxy for sending directives to the modem using AT commands. This facilitates the reading of responses or analyzing of events related to the modem.
For more information on the AT commands, see the nRF91x1 AT Commands Reference Guide.
Requirements¶
Before you start, check that you have the required hardware and software:
- 1x nRF9151 Connect Kit
- 1x nano-SIM card with LTE-M or NB-IoT support
- 1x U.FL cabled LTE-M/NB-IoT/NR+ Flexible Antenna (included in the box)
- 1x USB-C Cable
- A computer running macOS, Ubuntu, or Windows 10 or newer
Set up your board¶
- Insert the nano-SIM card into the nano-SIM card slot.
- Attach the U.FL cabled LTE-M/NB-IoT/NR+ Flexible Antenna.
- Connect the nRF9151 Connect Kit to the computer with a USB-C cable.
Building the sample¶
To build the sample, follow the instructions in Getting Started Guide to set up your preferred building environment.
Use the following steps to build the AT Client sample on the command line.
-
Open a terminal window.
-
Go to
NCS-Project/nrf9151-connectkit
repository cloned in the Getting Started Guide. -
Build the sample using the
west build
command, specifying the board (following the-b
option) asnrf9151_connectkit/nrf9151/ns
.The
-p
always option forces a pristine build, and is recommended for new users. Users may also use the-p auto
option, which will use heuristics to determine if a pristine build is required, such as when building another sample.Note
This sample has Cortex-M Security Extensions (CMSE) enabled and separates the firmware between Non-Secure Processing Environment (NSPE) and Secure Processing Environment (SPE). Because of this, it automatically includes the Trusted Firmware-M (TF-M).
-
After building the sample successfully, the firmware with the name
merged.hex
can be found in thebuild
directory.
Flashing the firmware¶
Set up your board before flashing the firmware. You can flash the sample using west flash
:
Tip
In case you wonder, the west flash
will execute the following command:
Testing¶
After programming the sample, test it by performing the following steps:
-
Open up a serial terminal, specifying the correct serial port that your computer uses to communicate with the nRF9151 SiP:
- Start PuTTY.
-
Configure the correct serial port and click Open:
-
Press the DFU/RST button to reset the nRF9151 SiP.
-
Once the sample starts running, you should see the following output:
-
Test the following commands from the terminal:
- This command retrieves the manufacturer identification.
- This command retrieves the System in Package (SiP) model identification.
- This command retrieves the modem firmware revision identification.
- This command retrieves the IMEI.
-
This command reads the current functional mode.
The read response parameter and its defined value are the following:
<fun>
- 0 – Minimum functionality mode. RF circuits are disabled by deactivating LTE and GNSS services.
- 1 – Normal mode. The active mode is either LTE or GNSS, or both. Full functional mode. Active modes depend on
%XSYSTEMMODE
setting. - 2 – Receive only mode in active system mode. Active modes depend on
%XSYSTEMMODE
setting. - 4 – Flight mode. RF circuits are disabled by deactivating LTE and GNSS services.
- 21 – LTE is activated.
- 31 – GNSS is activated.
- 41 – UICC is activated.
- This command sets the functional mode of the modem to normal.
- This command reads the IMSI from the SIM card.
Tip
You can refer to the nRF91x1 AT Commands Reference Guide to test more AT commands.