Make a copy of secretsExample.h and rename it to secrets.h. It must go inside the root directory of the project. Replace the values for the DEVEUI, APPEUI, and APPKEY with values as follows:
- DEVEUI: which can be found by scanning the QR code on the LoRaWan chip.
- APPEUI: currently we use the same APPEUI as the one for BraveButtons
- APPKEY: APPEUI = hex(str(hex(DEVEUI)) + str(hex(APPEUI))), where '+' is string concatenation An example one can be found in our private living doc.
Follow this guide on how to setup. The LoraBraveSensor directory can subsitute the Arduino Serial demo, as a guide on how to compile and upload our custom firmware. After going throught the entire process, I recommend using vscode's Arduino extension for easier file management.
I recommend using VSCode's Arduino extension for easier file management, after going through the setup process with the Arduino IDE at least once. After opening the project with VSCode, if you notice red squiggly error messages for missing includes, follow this guide on how to fix them. On Windows 10, the board firmware files can be found at C:/Users/{user}/AppData/Local/Arduino15/packages/rak_rui/hardware/stm32/3.4.2/cores/STM32WLE/component/rui_v3_api, and can be added under includePath of the .vscode/c_cpp_properties.json file.
Can be done with any serial monitor (e.g. Arduino, Arduino's VSCode Extension, PlatformIO, etc.) with BAUD rate of 115200. Remember to compile the file with DEBUG_LOG set to true, or DEBUG_LOG_MORE set to true in main.h to be able to see serial logs. Setting the two values to false for compiliation of production code can potentially reduce power consumption, by skipping unusable serial signals.
- Arduino for general firmware
- RAKwireless unified Interface V3 (RUI3) for hardware interfacing
- ArduinoJson for LoRaWAN data
Based on the state machine diagram from the original Particle BraveSensor
SPI_MOSI (PA7) is the inverted door pin (low is door open, high is door closed).
SPI_MISO (PA6) is the inverted motion pin (low is motion, high is no motion).
SPI_CLK (PA5) is the analog battery measurement pin (untested so far, usually returns 8### as the measurement).
SPI_CS (PA4) is the eeprom reset pin.
Assumes the usage of a binary door sensor, with a low being door open, and a high being door closed. The SP1_MOSI is the pin being used.
Assumes the usage of a binary motion sensor (such as the PIR), with a low meaning there is motion, and a high meaning there is no motion. The SP1_MISO is the pin being used.
The heartbeat system is ran on a timer provided by RAK's RUI3, and will send a message to AWS in HEARTBEAT_INTERVALms intervals.
OTAA is used to connect to the LoRaWan gateway, following this guide. Changes have been made, such as using a sub-band 2 (8 channels). Upon device start/restart, it will attempt to connect to a gateway thrice, over 30 seconds, and will go to sleep should that fail. LoRa send requests are also done up to three times, at two sends per request.
Downlink payload data use a base64 encoded json, e.g. , that is converted, and sent via AWS IoT for LoRaWan -> Devices -> Device ID -> Device Traffic -> Queue downlink message -> Payload field (any FPort will do).
For example: {"type":"heartbeat","battery":8192,"countdownTimer":10,"durationTimer":30,"stillnessTimer":30,"heartbeatInterval":60} encoded to eyJ0eXBlIjoiaGVhcnRiZWF0IiwiYmF0dGVyeSI6ODE5MiwiY291bnRkb3duVGltZXIiOjEwLCJkdXJhdGlvblRpbWVyIjozMCwic3RpbGxuZXNzVGltZXIiOjMwLCJoZWFydGJlYXRJbnRlcnZhbCI6NjB9
Uplinks can be viewed at AWS IoT for LoRaWan -> Test -> MQTT test client, and subscribing to rak3272/pub, with the payload being a base64 encoded json.
For example: eyJ0eXBlIjoiaGVhcnRiZWF0IiwiYmF0dGVyeSI6ODE5MiwiY291bnRkb3duVGltZXIiOjEwLCJkdXJhdGlvblRpbWVyIjozMCwic3RpbGxuZXNzVGltZXIiOjMwLCJoZWFydGJlYXRJbnRlcnZhbCI6NjB9
decodes to {"type":"heartbeat","battery":8192,"countdownTimer":10,"durationTimer":30,"stillnessTimer":30,"heartbeatInterval":60}).
The system is designed to go to sleep, unless there are changes to the digital input pins, or a timer interrupt. Limitation's of RUI3, results in a specific implementation -- more info can be found here. RAK_TIMER_#, are one of five hardware timers provided by RUI3.
Saving timers (e.g. countdown/duration/stillness) is done using the RUI3 flash library. The eeprom can be reset to the default values by rising the eeprom reset pin SPI_CS (PA4).