LoRaWAN Weather station created for VarnaLab in Micropython

За български език ТУК

This project uses the following libs:

1. LoRaWAN for micropython: here
2. SDS011 micropython driver: here
3. BME280 micropython driver: here

Components

1. SDS011 dust sensor

2. BME280 temperature, pressure and humidity sensor

3. Microcontroller LILYGO TTGO LORA32

You should download the specific micropython firmware from here

Pinout

Connections

bmе280 works over I2C bus. Connect to the following MCU pins sda = 21, scl= 22

Dust sensor works over UART. Connect to the following MCU pins rx = 16, tx = 17

Configurations settings

Wifi and The Things Network settings are located in the file config.py You have to create a device in TTN. It works only with ABP authentication since micropython driver doesn't support OTAA. The file ttn_payload_formatter_function.js contains а javascript function which formats the payload for TTN processing. Don't forget to change above_sea_level variable in that function to match your location's altitude in meters. This function has to be put in the following place in TTN:

Applications > [your application] > End devices > eui-[your device id] > Payload formatters > Uplink

This function is made to work with the struct, located in the MCU code.

File upload

It is important to upload the files on the MCU with the following file structure:

Extras (Bluetooth)

There is a class (esp32ble.py) in Extras folder, which class allows using the esp32 bluetooth. I still haven't implemented it in the main.py file, but it can be used for UART debug, while the weather station is working. There is sample code in the same folder.

Extras (MQTT)

Lilygo micropython formware doesn't have umqtt module preinstalled, so you have to upload the umqtt directory from the repo to your board.