The Minimalistic Node
For the implementation of the first minimalistic LoRa remote node we have employed the following components:
- Arduino Mini accessed by means of an FTDI serial interface
- HopeRF RF96 LoRa TX/RX module (see HopeRF website about LoRa transceiver
The node schematic is available in this repository under Devices/Arduino/LoraWAN/Arduino%20_connections
Here is the breadboard level implementation of the node:
The Arduino Software is derived from the open source project LMIC available on Github. LMIC has been developed to integrate Arduino to The Things Network infastructure, but can be used for any LoRa network with very few changes.
The Arduino code we used is available in this repository under the Devices/Arduino/LoraWAN/otaa-DHT22 folder and is a direct porting of the LMIC code (there are still references to TTN in the comments). In particulra it is necessary to configure two important identifier to ensure proper registration into the LoRa network: the DevEUI and the AppKey. See below for explanation about these two items.