LoRa AT Commands Configuration
This document describes how to configure HARDWARIO TOWER LoRa devices with AT commands over a USB virtual serial port.
This document does not explain project-specific firmware commands and functions. They are explained in the project itself.
These commands apply to all firmware in the HARDWARIO Playground with the prefix twr-lora-.
LoRa Configuration
The LoRa module can be configured with AT commands sent to the Core Module over a USB virtual serial port.
The easiest way to configure the LoRa Module is with our HARDWARIO Console which is a part of the HARDWARIO Code.
You can also use a terminal emulator application such as Hterm, Putty, Picocom.
Parameters for the configuration are:
- Baud 115200
- 8 data bits, 1 stop bit, no parity (8N1)
CR+LFas the end-of-line sequence for both transmit and receive
About AT Commands
To list all possible commands use AT$HELP. The set of supported commands will depend on your firmware version.
AT$HELP Example Output
AT$HELP
AT$DEVEUI
AT$DEVADDR
AT$NWKSKEY
AT$APPSKEY
AT$APPKEY
AT$APPEUI
AT$BAND 0:AS923, 1:AU915, 5:EU868, 6:KR920, 7:IN865, 8:US915
AT$MODE 0:ABP, 1:OTAA
AT$NWK Network type 0:private, 1:public
AT$ADR Automatic data rate 0:disabled, 1:enabled
AT$DR Data rate 0-15
AT$REPU Repeat of unconfirmed transmissions 1-15
AT$REPC Repeat of confirmed transmissions 1-8
AT$JOIN Send OTAA Join packet
AT$FRMCNT Get frame counters
AT$LNCHECK MAC Link Check
AT$RFQ Get RSSI/SNR of last RX packet
AT$DEBUG Show debug UART communication
AT$REBOOT Firmware reboot
AT$FRESET LoRa Module factory reset
AT$SEND Immediately send packet
AT$STATUS Show status
AT$BLINK LED blink 3 times
AT$LED LED on/off
AT+CLAC List all available AT commands
AT$HELP This help
Read Value
To read the value of a variable, you just have to append the question mark ? to the end of the corresponding AT command
AT$APPSKEY?
The current value of the variable will be shown in the terminal
APPSKEY: BF22C15EB89237A65DAABB05B2C91EB4
Update Value
To update the value of the variable use the following syntax of a variable followed by = and the desired value
AT$APPSKEY=BF22C15EB89237A65DAABB05B2C91EB4
You can use online key generators for testing purposes.
OTAA - Over-the-Air Activation
OTAA means that the session keys (the ones with S in the name) are generated in the LoRa network during JOIN. The keys are then automatically transferred to your LoRa module.
If your LoRa network does not support the OTAA activation method, read the ABP section below. If you are not sure which activation type to use, start with OTAA.
For the OTAA activation method, the LoRa network needs to know the DevEUI of your LoRa module. You can read the value with the command AT$DEVEUI?, you should get back something like this
$DEVEUI: 009335FF931FEADC
OK
The LoRa network also needs to know the APPKEY and APPEUI values. You can either read the values from your LoRa module and transfer them into your LoRa network, or you can let the LoRa network generate new values for you to set in your module, for example:
AT$APPEUI=324502A5676BADD7
OK
AT$APPKEY=44D4A5DA7A9507F036C5A2750211F052
OK
Each time you get an OK, the value has been saved in the LoRa module’s internal flash memory.
Some LoRa networks also support generating DEVEUI but we do not recommend changing this value.
Finally, switch the modem into OTAA mode and send a JOIN command to exchange the session keys. Make sure your modem has a good signal because it needs bidirectional communication with the gateway to complete the JOIN.
AT$MODE=1 // Set OTAA(1)
OK
AT$NWK=1 // Public(1) or private(0) network config (TTN is public)
OK
AT$JOIN
OK
$JOIN_OK
Note that the OK response to JOIN command does not mean that the join was successful. Wait for a few seconds to get either $JOIN_OK (join was successful) or $JOIN_ERROR (join failed). If the join was successful, the LoRa module is ready to communicate.
ABP - Activation by Personalization
ABP means that you set up session keys manually. AT$MODE has to be set to 0 (ABP), which is the default setting after a LoRa module power reset.
If you use the ABP mode, you need to set the APPSKEY and NWKSKEY values manually via the corresponding AT commands.
AT$APPSKEY=5505CA3E4620843B324502A5676BADD7
OK
AT$NWKSKEY=44D4A5DA7A9507F036C5A2750211F050
OK
Each time you get an OK, the value has been saved in the LoRa module’s internal flash memory.
The LoRa network will need to know the DEVEUI and DEVADDR values from your LoRa module.
Use the commands AT$DEVEUI? and AT$DEVADDR? to read the values.
AT$DEVEUI?
$DEVEUI: 009335FF931FEADC
OK
AT$DEVADDR?
$DEVADDR: 26012C39
OK