Heltec Esp32 LoRaWan library

This is a Platformio library for Heltec ESP32 boards with integrated LoRa transceivers. The code is directly ported from the original Heltec Arduino library: https://github.com/Heltec-Aaron-Lee/WiFi_Kit_series

As the specific LoRaWan Platformio library seems no more being maintained, and it is not compatible with espressif32 platform versions higher than 3.5.0, I decided to create this new library.

Supported boards

• Heltec WiFi LoRa 32 (V1, V2 and V3)
• Heltec Wireless Stick
• Heltec Wireless Stick Lite, including V3

Configuration

You need to define some constants in the build_flags option inside platformio.ini file.

[env:esp32]
platform = espressif32
framework = arduino
build_flags =
    -D LoRaWAN_DEBUG_LEVEL=3
    -D LORAWAN_PREAMBLE_LENGTH=8
    -D REGION_EU433
    -lheltec

When using ESP32-S3 devices, such as WiFi LoRa 32 V3 or Heltec Wireless Stick Lite V3, you need to replace flag -lheltec with --lheltec_s3.

To show debug information about LoRa activity on the embedded Oled screen, you can optionally add the LORA_DISPLAY constant:

build_flags =
    -D LoRaWAN_DEBUG_LEVEL=3
    -D LORAWAN_PREAMBLE_LENGTH=8
    -D REGION_EU433
    -lheltec
    -D LORA_DISPLAY

In this case, you need to add also the Oled library Heltec_Esp32_Display to the project dependencies.