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.
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//---------------------------------------------------------------------------------
//#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.
devMobile's blog 