The source code of my nanoFramework RFM9X/SX127X library is now available on GitHub. One test harness uses an STM32F429 Discovery and a dragino technology LoRa shield for Arduino with some jumper wires.

The other uses Sparkfun LoRa Gateway 1 Channel ESP32 for a LoRaWAN.

A sample application which shows how to send/receive address/un-addressed payloads.
//--------------------------------------------------------------------------------- // Copyright (c) April/May 2020, devMobile Software // // Licensed under the Apache License, Version 2.0 (the "License"); // you may not use this file except in compliance with the License. // You may obtain a copy of the License at // // http://www.apache.org/licenses/LICENSE-2.0 // // Unless required by applicable law or agreed to in writing, software // distributed under the License is distributed on an "AS IS" BASIS, // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. // See the License for the specific language governing permissions and // limitations under the License. // //--------------------------------------------------------------------------------- //#define ADDRESSED_MESSAGES_PAYLOAD #define ST_STM32F429I_DISCOVERY //nanoff --target ST_STM32F429I_DISCOVERY --update //#define ESP32_WROOM_32_LORA_1_CHANNEL //nanoff --target ESP32_WROOM_32 --serialport COM4 --update namespace devMobile.IoT.Rfm9x.LoRaDeviceClient { using System; using System.Text; using System.Threading; #if ESP32_WROOM_32_LORA_1_CHANNEL using nanoFramework.Hardware.Esp32; #endif using devMobile.IoT.Rfm9x; class Program { const double Frequency = 915000000.0; #if ST_STM32F429I_DISCOVERY private const string SpiBusId = "SPI5"; #endif #if ESP32_WROOM_32_LORA_1_CHANNEL private const string SpiBusId = "SPI1"; #endif static void Main() { byte MessageCount = System.Byte.MaxValue; #if ADDRESSED_MESSAGES_PAYLOAD const string HostName = "ESP32LoRa"; const string DeviceName = "LoRaIoT1"; #else const string DeviceName = "ESP32LoRa"; #endif #if ST_STM32F429I_DISCOVERY int chipSelectPinNumber = PinNumber('C', 2); int resetPinNumber = PinNumber('C', 3); int interruptPinNumber = PinNumber('A', 4); #endif #if ESP32_WROOM_32_LORA_1_CHANNEL int chipSelectPinNumber = Gpio.IO16; int interruptPinNumber = Gpio.IO26; Configuration.SetPinFunction(Gpio.IO12, DeviceFunction.SPI1_MISO); Configuration.SetPinFunction(Gpio.IO13, DeviceFunction.SPI1_MOSI); Configuration.SetPinFunction(Gpio.IO14, DeviceFunction.SPI1_CLOCK); Rfm9XDevice rfm9XDevice = new Rfm9XDevice(SpiBusId, chipSelectPinNumber, interruptPinNumber); #endif #if ST_STM32F429I_DISCOVERY Rfm9XDevice rfm9XDevice = new Rfm9XDevice(SpiBusId, chipSelectPinNumber, resetPinNumber, interruptPinNumber); #endif rfm9XDevice.Initialise(Frequency, paBoost: true, rxPayloadCrcOn: true); #if DEBUG rfm9XDevice.RegisterDump(); #endif rfm9XDevice.OnReceive += Rfm9XDevice_OnReceive; #if ADDRESSED_MESSAGES_PAYLOAD rfm9XDevice.Receive(UTF8Encoding.UTF8.GetBytes(DeviceName)); #else rfm9XDevice.Receive(); #endif rfm9XDevice.OnTransmit += Rfm9XDevice_OnTransmit; Thread.Sleep(10000); while (true) { string messageText = string.Format("Hello from {0} ! {1}", DeviceName, MessageCount); MessageCount -= 1; byte[] messageBytes = UTF8Encoding.UTF8.GetBytes(messageText); Console.WriteLine(string.Format("{0}-TX {1} byte message {2}", DateTime.UtcNow.ToString("HH:mm:ss"), messageBytes.Length, messageText)); #if ADDRESSED_MESSAGES_PAYLOAD rfm9XDevice.Send(UTF8Encoding.UTF8.GetBytes(HostName), messageBytes); #else rfm9XDevice.Send(messageBytes); #endif Thread.Sleep(10000); } } private static void Rfm9XDevice_OnReceive(object sender, Rfm9XDevice.OnDataReceivedEventArgs e) { try { // Remove unprintable characters from messages for (int index = 0; index < e.Data.Length; index++) { if ((e.Data[index] < 0x20) || (e.Data[index] > 0x7E)) { e.Data[index] = 0x20; } } string messageText = UTF8Encoding.UTF8.GetString(e.Data, 0, e.Data.Length); #if ADDRESSED_MESSAGES_PAYLOAD string addressText = UTF8Encoding.UTF8.GetString(e.Address, 0, e.Address.Length); Console.WriteLine(string.Format(@"{0}-RX From {1} PacketSnr {2} Packet RSSI {3}dBm RSSI {4}dBm ={5} ""{6}""", DateTime.UtcNow.ToString("HH:mm:ss"), addressText, e.PacketSnr, e.PacketRssi, e.Rssi, e.Data.Length, messageText)); #else Console.WriteLine(string.Format(@"{0}-RX PacketSnr {1} Packet RSSI {2}dBm RSSI {3}dBm ={4} ""{5}""", DateTime.UtcNow.ToString("HH:mm:ss"), e.PacketSnr, e.PacketRssi, e.Rssi, e.Data.Length, messageText)); #endif } catch (Exception ex) { Console.WriteLine(ex.Message); } } private static void Rfm9XDevice_OnTransmit(object sender, Rfm9XDevice.OnDataTransmitedEventArgs e) { Console.WriteLine( string.Format("{0}-TX Done", DateTime.UtcNow.ToString("HH:mm:ss"))); } #if ST_STM32F429I_DISCOVERY static int PinNumber(char port, byte pin) { if (port < 'A' || port > 'J') throw new ArgumentException(); return ((port - 'A') * 16) + pin; } #endif } }
The addressing support is pretty basic as my goal was a library that I could extend with optional functionality like tamper detection via signing and privacy via payload encryption, mesh network support etc.
The library works but should be treated as early beta.