1.8 KiB
ttn-esp32
The Things Network device library for ESP-IDF (ESP32) supporting devices with Semtech SX127x chips
This ESP32 component provides LoRaWAN communication with The Things Network. It supports OTAA (over-the-air activation), uplink and downlink messages and saving the EUIs and key in non-volatile memory.
The library is based on the LMIC library from IBM and provides a high-level API specifically targeted at The Things Network.
Get Started
Follow the detailed Get Started Guide in the Wiki.
Supported Boards
All boards with Semtech SX127x chips, RFM9x and compatibles are supported. It includes boards from ttgo, Heltec and HopeRF.
Resources
SPI bus and pins
Before the TTN device is configured, the SPI bus / host (SPI_HOST, HSPI_HOST or VSPI_HOST) must be configured by calling spi_bus_initialize(). In the SPI configuration, the pin number for SCK, MISO and MOSI are specified.
The pin number of NSS (the radio chip's SPI chip select) is specified by calling TheThingsNetwork::configurePins().
The SPI bus frequency can be changed by running make menuconfig.
SX127x pins
Except for the SPI pins, the pins connected to the SX127x radio chip are configured by calling TheThingsNetwork::configurePins(). The pins RXTX and RTS are optional. The chip can be used without connecting them.
Timer
To implement the LoRaWAN protocol, a timer is needed. The ESP32 has four timers. By default,
timer 1 of timer group 0 is used. It can be changed by running make menuconfig.
Background thread
Most of the LoRaWAN code is run in a background process with high priority (as the timing is crucial). The default priority is 10. It can be changed by running make menuconfig.