TinyCLR OS V2 Seeed LoRa-E5 LoRaWAN library Part2

Nasty OTAA connect

After getting basic connectivity for my Seeedstudio LoRa-E5 Development Kit and Fezduino test rig working I wanted to see if I could get the device connected to The Things Industries(TTI) via the RAK7258 WisGate Edge Lite on the shelf in my office.

My Over the Air Activation (OTAA) implementation is very “nasty” as it is assumed that there are no timeouts or failures and it only sends one BCD message “48656c6c6f204c6f526157414e” which is “hello LoRaWAN”. The code just sequentially steps through the necessary commands (with a suitable delay after each is sent) to join the TTI network.

public class Program
{
#if TINYCLR_V2_FEZDUINO
   private static string SerialPortId = SC20100.UartPort.Uart5;
#endif
   private const string AppKey = "................................";

   //txByteCount = serialDevice.Write(UTF8Encoding.UTF8.GetBytes($"AT+ID=AppEui,{AppEui}\r\n"));
   //private const string AppEui = "................";

   //txByteCount = serialDevice.Write(UTF8Encoding.UTF8.GetBytes($"AT+ID=AppEui,\"{AppEui}\"\r\n"));
   private const string AppEui = ".. .. .. .. .. .. .. ..";

   private const byte messagePort = 1;

   //private const string payload = "48656c6c6f204c6f526157414e"; // Hello LoRaWAN
   private const string payload = "01020304"; // AQIDBA==
   //private const string payload = "04030201"; // BAMCAQ==

   public static void Main()
   {
      UartController serialDevice;
      int txByteCount;
      int rxByteCount;

      Debug.WriteLine("devMobile.IoT.SeeedE5.NetworkJoinOTAA starting");

      try
      {
         serialDevice = UartController.FromName(SerialPortId);

         serialDevice.SetActiveSettings(new UartSetting()
         {
            BaudRate = 9600,
            Parity = UartParity.None,
            StopBits = UartStopBitCount.One,
            Handshaking = UartHandshake.None,
            DataBits = 8
         });

         serialDevice.Enable();

         // Set the Region to AS923
         txByteCount = serialDevice.Write(UTF8Encoding.UTF8.GetBytes("AT+DR=AS923\r\n"));
         Debug.WriteLine($"TX: DR {txByteCount} bytes");
         Thread.Sleep(500);

         // Read the response
         rxByteCount = serialDevice.BytesToRead;
         if (rxByteCount > 0)
         {
            byte[] rxBuffer = new byte[rxByteCount];
            serialDevice.Read(rxBuffer);
            Debug.WriteLine($"RX :{UTF8Encoding.UTF8.GetString(rxBuffer)}");
         }

         // Set the Join mode
         txByteCount = serialDevice.Write(UTF8Encoding.UTF8.GetBytes("AT+MODE=LWOTAA\r\n"));
         Debug.WriteLine($"TX: MODE {txByteCount} bytes");
         Thread.Sleep(500);

         // Read the response
         rxByteCount = serialDevice.BytesToRead;
         if (rxByteCount > 0)
         {
            byte[] rxBuffer = new byte[rxByteCount];
            serialDevice.Read(rxBuffer);
            Debug.WriteLine($"RX :{UTF8Encoding.UTF8.GetString(rxBuffer)}");
         }

         // Set the appEUI
         txByteCount = serialDevice.Write(UTF8Encoding.UTF8.GetBytes($"AT+ID=AppEui,\"{AppEui}\"\r\n"));
         Debug.WriteLine($"TX: ID=AppEui {txByteCount} bytes");
         Thread.Sleep(500);

         // Read the response
         rxByteCount = serialDevice.BytesToRead;
         if (rxByteCount > 0)
         {
            byte[] rxBuffer = new byte[rxByteCount];
            serialDevice.Read(rxBuffer);
            Debug.WriteLine($"RX :{UTF8Encoding.UTF8.GetString(rxBuffer)}");
         }
            
         // Set the appKey
         txByteCount = serialDevice.Write(UTF8Encoding.UTF8.GetBytes($"AT+KEY=APPKEY,{AppKey}\r\n"));
         Debug.WriteLine($"TX: KEY=APPKEY {txByteCount} bytes");
         Thread.Sleep(500);

         // Read the response
         rxByteCount = serialDevice.BytesToRead;
         if (rxByteCount > 0)
         {
            byte[] rxBuffer = new byte[rxByteCount];
            serialDevice.Read(rxBuffer);
            Debug.WriteLine($"RX :{UTF8Encoding.UTF8.GetString(rxBuffer)}");
         }

         // Set the PORT
         txByteCount = serialDevice.Write(UTF8Encoding.UTF8.GetBytes($"AT+PORT={messagePort}\r\n"));
         Debug.WriteLine($"TX: PORT {txByteCount} bytes");
         Thread.Sleep(500);

         // Read the response
         rxByteCount = serialDevice.BytesToRead;
         if (rxByteCount > 0)
         {
            byte[] rxBuffer = new byte[rxByteCount];
            serialDevice.Read(rxBuffer);
            Debug.WriteLine($"RX :{UTF8Encoding.UTF8.GetString(rxBuffer)}");
         }

         // Join the network
         txByteCount = serialDevice.Write(UTF8Encoding.UTF8.GetBytes("AT+JOIN\r\n"));
         Debug.WriteLine($"TX: JOIN {txByteCount} bytes");
         Thread.Sleep(10000);

         // Read the response
         rxByteCount = serialDevice.BytesToRead;
         if (rxByteCount > 0)
         {
            byte[] rxBuffer = new byte[rxByteCount];
            serialDevice.Read(rxBuffer);
            Debug.WriteLine($"RX :{UTF8Encoding.UTF8.GetString(rxBuffer)}");
         }

         while (true)
         {
            // Unconfirmed message
            txByteCount = serialDevice.Write(UTF8Encoding.UTF8.GetBytes($"AT+MSGHEX=\"{payload}\"\r\n"));
            Debug.WriteLine($"TX: MSGHEX {txByteCount} bytes");

            // Confirmed message
            //txByteCount = serialDevice.Write(UTF8Encoding.UTF8.GetBytes($"AT+CMSGHEX=\"{payload}\"\r\n"));
            //Debug.WriteLine($"TX: CMSGHEX {txByteCount} bytes");

            Thread.Sleep(10000);

            // Read the response
            rxByteCount = serialDevice.BytesToRead;
            if (rxByteCount > 0)
            {
               byte[] rxBuffer = new byte[rxByteCount];
               serialDevice.Read(rxBuffer);
               Debug.WriteLine($"RX :{UTF8Encoding.UTF8.GetString(rxBuffer)}");
            }

            Thread.Sleep(30000);
         }
      }
      catch (Exception ex)
      {
         Debug.WriteLine(ex.Message);
      }
   }
}

The code is not suitable for production but it confirmed my software and hardware configuration worked.

The thread '<No Name>' (0x2) has exited with code 0 (0x0).
devMobile.IoT.SeeedE5.NetworkJoinOTAA starting
TX: DR 13 bytes
RX :+DR: AS923

TX: MODE 16 bytes
RX :+MODE: LWOTAA

TX: ID=AppEui 40 bytes
RX :+ID: AppEui, ..:..:.:.:.:.:.:.

TX: KEY=APPKEY 48 bytes
RX :+KEY: APPKEY ................................

TX: PORT 11 bytes
RX :+PORT: 1

TX: JOIN 9 bytes
RX :+JOIN: Start
+JOIN: NORMAL
+JOIN: Network joined
+JOIN: NetID 000013 DevAddr ..:..:..:..
+JOIN: Done

TX: MSGHEX 22 bytes
RX :+MSGHEX: Start
+MSGHEX: FPENDING
+MSGHEX: RXWIN1, RSSI -41, SNR 9.0
+MSGHEX: Done

TX: MSGHEX 22 bytes
RX :+MSGHEX: Start
+MSGHEX: Done

In the Visual Studio 2019 debug output I could see messages getting sent and then after a short delay they were visible in the TTI console.

Seeed E5 LoRaWAN dev Kit connecting in The Things Industries Device Live data tab

I had an issue with how the AppUI parameter was handled

   private const string AppKey = "................................";

   //txByteCount = serialDevice.Write(UTF8Encoding.UTF8.GetBytes($"AT+ID=AppEui,{AppEui}\r\n"));
   //private const string AppEui = "................";

   //txByteCount = serialDevice.Write(UTF8Encoding.UTF8.GetBytes($"AT+ID=AppEui,\"{AppEui}\"\r\n"));
   private const string AppEui = ".. .. .. .. .. .. .. ..";


It appears that If the appkey (or other string parameter) has spaces it has to be enclosed in quotations.

TinyCLR OS V2 Seeed LoRa-E5 LoRaWAN library Part1

Basic connectivity

Today I have been working on a GHI Electronics TinyCLR V2  C# library for the Seeedstudio LoRa-E5 module using my Seeedstudio LoRa-E5 Development Kit.

My initial test rig is based on an Fezduino board with a Grove Base Shield V2.0 connected to
LoRa-E5 Development Kit by a Grove – Universal 4 Pin 20cm Unbuckled Cable(TX/RX reversed)

Fezduino Seeed LoRaE5 test rig

The code has compile time options for synchronous and asynchronous operation.

public class Program
{
   private static UartController serialDevice;
   private const string ATCommand = "at+ver\r\n";
#if TINYCLR_V2_FEZDUINO
   private static readonly string SerialPortId = SC20100.UartPort.Uart5;
#endif
#if TINYCLR_V2_SC20100DEV_MIKROBUS_1
   private const string SerialPortId = SC20100.UartPort.Usart2;
#endif
#if TINYCLR_V2_SC20100DEV_MIKROBUS_2
   private const string SerialPortId = SC20100.UartPort.Uart3;
#endif

   public static void Main()
   {
      Debug.WriteLine("devMobile.IoT.SeeedE5.ShieldSerial starting");

      try
      {
         serialDevice = UartController.FromName(SerialPortId);

         serialDevice.SetActiveSettings(new UartSetting()
         {
            BaudRate = 9600,
            Parity = UartParity.None,
            StopBits = UartStopBitCount.One,
            Handshaking = UartHandshake.None,
            DataBits = 8
         });

         serialDevice.Enable();

#if SERIAL_ASYNC_READ
         serialDevice.DataReceived += SerialDevice_DataReceived;
#endif

         while (true)
         {
            byte[] txBuffer = UTF8Encoding.UTF8.GetBytes(ATCommand);

            int txByteCount = serialDevice.Write(txBuffer);
            Debug.WriteLine($"TX: {txByteCount} bytes");

#if SERIAL_SYNC_READ
            while( serialDevice.BytesToWrite>0)
            {
               Debug.WriteLine($" BytesToWrite {serialDevice.BytesToWrite}");
               Thread.Sleep(100);
            }

            int rxByteCount = serialDevice.BytesToRead;
            if (rxByteCount>0)
            {
               byte[] rxBuffer = new byte[rxByteCount];

               serialDevice.Read(rxBuffer);

               Debug.WriteLine($"RX sync:{rxByteCount} bytes read");
               String response = UTF8Encoding.UTF8.GetString(rxBuffer);
               Debug.WriteLine($"RX sync:{response}");
            }
#endif

            Thread.Sleep(20000);
         }
      }
      catch (Exception ex)
      {
         Debug.WriteLine(ex.Message);
      }
   }

#if SERIAL_ASYNC_READ
   private static void SerialDevice_DataReceived(UartController sender, DataReceivedEventArgs e)
   {
      byte[] rxBuffer = new byte[e.Count];

      sender.Read(rxBuffer, 0, e.Count);

      Debug.WriteLine($"RX Async:{e.Count} bytes read");
      String response = UTF8Encoding.UTF8.GetString(rxBuffer);
      Debug.WriteLine($"RX Async:{response}");
   }
#endif
}

When I first ran the code no data was received so I doubled checked the serial connections and figured out I had to modify the cable and reverse the TX and RX pins.

The thread '<No Name>' (0x2) has exited with code 0 (0x0).
devMobile.IoT.SeeedLoRaE5.ShieldSerial starting
TX: 8 bytes
RX Async:1 bytes read
RX Async:+
RX Async:8 bytes read
RX Async:VER: 4.0
RX Async:5 bytes read
RX Async:.11

TX: 8 bytes
RX Async:1 bytes read
RX Async:+
RX Async:9 bytes read
RX Async:VER: 4.0.
RX Async:4 bytes read
RX Async:11

RFM9X.TinyCLR V2 RC2 on Github

The source code of RC2 of my GHI Electronics TinyCLR-0SV2RC1 RFM9X/SX127X library is live on GitHub. The sample application now supports Fezduino(dragino_LoRa shield for Arduino + others), Fezportal and the SC2010 Dev board (with CascoLogix LoRa Click) . I will add FezFeather and Fezstick support soon.

//---------------------------------------------------------------------------------
// Copyright (c) March/April 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.
//
// Need one of TINYCLR_V2_SC20100DEV_MIKROBUS_1/TINYCLR_V2_SC20100DEV_MIKROBUS_2/TINYCLR_V2_FEZDUINO/TINYCLR_V2_FEZPORTAL defined
//---------------------------------------------------------------------------------
namespace devMobile.IoT.Rfm9x.LoRaDeviceClient
{
	using System;
	using System.Diagnostics;
	using System.Text;
	using System.Threading;

	using GHIElectronics.TinyCLR.Pins;

	using devMobile.IoT.Rfm9x;

	class Program
   {
      static void Main()
      {
#if TINYCLR_V2_SC20100DEV_MIKROBUS_1 || TINYCLR_V2_SC20100DEV_MIKROBUS_2
			const string DeviceName = "SC20100DEVLoRa";
#endif
#if TINYCLR_V2_FEZDUINO
			const string DeviceName = "FezduinoLoRa";
#endif
#if TINYCLR_V2_FEZPORTAL
			const string DeviceName = "FezportalLoRa";
#endif
#if ADDRESSED_MESSAGES_PAYLOAD
			const string HostName = "LoRaIoT1";
#endif
			const double Frequency = 915000000.0;
			byte MessageCount = System.Byte.MaxValue;
#if TINYCLR_V2_SC20100DEV_MIKROBUS_1
         Rfm9XDevice rfm9XDevice = new Rfm9XDevice(SC20100.SpiBus.Spi3, SC20100.GpioPin.PD3, SC20100.GpioPin.PD4, SC20100.GpioPin.PC5);
#endif
#if TINYCLR_V2_SC20100DEV_MIKROBUS_2
			Rfm9XDevice rfm9XDevice = new Rfm9XDevice(SC20100.SpiBus.Spi3, SC20100.GpioPin.PD14, SC20100.GpioPin.PD15, SC20100.GpioPin.PA8);
#endif
#if TINYCLR_V2_FEZDUINO
			Rfm9XDevice rfm9XDevice = new Rfm9XDevice(SC20100.SpiBus.Spi6, SC20100.GpioPin.PB1, SC20100.GpioPin.PA15, SC20100.GpioPin.PA1);
#endif
#if TINYCLR_V2_FEZPORTAL
         Rfm9XDevice rfm9XDevice = new Rfm9XDevice(SC20100.SpiBus.Spi3, SC20100.GpioPin.PC13, SC20100.GpioPin.PD4,SC20100.GpioPin.PC2);
#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);
				Debug.WriteLine($"{DateTime.Now:HH:mm:ss}-TX {messageBytes.Length} byte message {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
			{
				string messageText = UTF8Encoding.UTF8.GetString(e.Data);

#if ADDRESSED_MESSAGES_PAYLOAD
				string addressText = UTF8Encoding.UTF8.GetString(e.Address);

				Debug.WriteLine($@"{DateTime.Now:HH:mm:ss}-RX From {addressText} PacketSnr {e.PacketSnr} Packet RSSI {e.PacketRssi}dBm RSSI {e.Rssi}dBm = {e.Data.Length} byte message ""{messageText}""");
#else
				Debug.WriteLine($@"{DateTime.Now:HH:mm:ss}-RX PacketSnr {e.PacketSnr} Packet RSSI {e.PacketRssi}dBm RSSI {e.Rssi}dBm = {e.Data.Length} byte message ""{messageText}""");
#endif
			}
			catch (Exception ex)
			{
				Debug.WriteLine(ex.Message);
			}
		}

		private static void Rfm9XDevice_OnTransmit(object sender, Rfm9XDevice.OnDataTransmitedEventArgs e)
		{
			Debug.WriteLine($"{DateTime.Now:HH:mm:ss}-TX Done");
		}
	}
}

The library works but should be treated as late beta.

TinyCLR OS V2 RC1 LoRa library Part4

Interrupts Revisited

In my last post I had two approaches for fixing the issue with transmit interrupts. As I was sorting out the configuration for my Fezportal device and SS20100 Dev board(both sockets) with a Cascologix MikroBus LoRa click I had similar issues with both receive and transmit.

SC20100 Dev Rev A with Cascologix Click in socket1
Fezportal with Cascologix click

I noticed the extra RegIrqFlags 0X58, Receive-Message in the debugging output.

The thread '<No Name>' (0x2) has exited with code 0 (0x0).
Sending 13 bytes message Hello LoRa 1!
RegIrqFlags 0X08
Transmit-Done
Sending 13 bytes message Hello LoRa 2!
RegIrqFlags 0X08
Transmit-Done
RegIrqFlags 0X58
Receive-Message
Received 23 byte message  �LoRaIoT1N3WT 20.5,H 86
Transmit-Done
Sending 13 bytes message Hello LoRa 3!
RegIrqFlags 0X08
Transmit-Done

This was with the modified device write methods so I tried changing the Serial Peripheral Interface(SPI) configuration.

public RegisterManager(string spiPortName,  int chipSelectPin, int clockFrequency = 500000)
{
	GpioPin chipSelectGpio = GpioController.GetDefault().OpenPin(chipSelectPin);

	var settings = new SpiConnectionSettings()
	{
		ChipSelectType = SpiChipSelectType.Gpio,
		ChipSelectLine = chipSelectGpio,
		Mode = SpiMode.Mode0,
		ClockFrequency = clockFrequency,
		ChipSelectActiveState = false,
		ChipSelectHoldTime = new TimeSpan(1),
	};

	SpiController spiController = SpiController.FromName(spiPortName);

	rfm9XLoraModem = spiController.GetDevice(settings);
}

When I added the ChipSelectHoldTime (even the smallest possible one) the code worked as expected.

The thread '' (0x2) has exited with code 0 (0x0).
Sending 13 bytes message Hello LoRa 1!
RegIrqFlags 0X08
Transmit-Done
Sending 13 bytes message Hello LoRa 2!
RegIrqFlags 0X08
Transmit-Done
RegIrqFlags 0X50
Receive-Message
Received 23 byte message �LoRaIoT1N3WT 20.5,H 87
Sending 13 bytes message Hello LoRa 3!
RegIrqFlags 0X08
Transmit-Done
Sending 13 bytes message Hello LoRa 4!
RegIrqFlags 0X08
Transmit-Done

At this point I have run out of ideas so I will release the code this fix.

RAK811LoRaWAN.TinyCLR on Github

The source code of my TinyCLR V2 RAK811 Module library is now available on GitHub. My demonstration application uses a FezDuino and a modified RAK811 LPWAN Evaluation Board(EVB).

FezDuino with EVB plugged into Arduino headers

A sample application which shows how to connect using Over the Air Activation(OTAA) or Activation By Personalisation(ABP) then send and receive byte array/Binary Coded Decimal(BCD) messages .

//---------------------------------------------------------------------------------
// Copyright (c) July 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.
//
// must have one of 
//    TINYCLR_V2_FEZDUINO or
//    PAYLOAD_BCD or PAYLOAD_BYTES defined
//    OTAA or ABP
//
// For confirmed messages define CONFIRMED
//---------------------------------------------------------------------------------
namespace devMobile.IoT.Rak811LoRaWanDeviceClient
{
   using System;
   using System.Threading;
   using System.Diagnostics;

   using GHIElectronics.TinyCLR.Pins;
   using GHIElectronics.TinyCLR.Devices.Uart;

   using devMobile.IoT.LoRaWan;

   public class Program
   {
#if TINYCLR_V2_FEZDUINO
      private const string SerialPortId = SC20100.UartPort.Uart5;
#endif
#if OTAA
      private const string DevEui = "...";
      private const string AppEui = "...";
      private const string AppKey = "...";
#endif
#if ABP
      private const string DevAddress = "...";
      private const string NwksKey = "...";
      private const string AppsKey = "...";
#endif
      private const string Region = "AS923";
      private static readonly TimeSpan JoinTimeOut = new TimeSpan(0, 0, 10);
      private static readonly TimeSpan SendTimeout = new TimeSpan(0, 0, 10);
      private const byte MessagePort = 1;
#if PAYLOAD_BCD
      private const string PayloadBcd = "48656c6c6f204c6f526157414e"; // Hello LoRaWAN in BCD
#endif
#if PAYLOAD_BYTES
      private static readonly byte[] PayloadBytes = { 0x48, 0x65, 0x6c, 0x6c, 0x6f, 0x20, 0x4c, 0x6f, 0x52, 0x61, 0x57, 0x41, 0x4e}; // Hello LoRaWAN in bytes
#endif

      public static void Main()
      {
         Result result;

         Debug.WriteLine("devMobile.IoT.Rak811LoRaWanDeviceClient starting");

         try
         {
            using (Rak811LoRaWanDevice device = new Rak811LoRaWanDevice())
            {
               result = device.Initialise(SerialPortId, 9600, UartParity.None, 8, UartStopBitCount.One);
               if (result != Result.Success)
               {
                  Debug.WriteLine($"Initialise failed {result}");
                  return;
               }

#if CONFIRMED
               device.OnMessageConfirmation += OnMessageConfirmationHandler;
#endif
               device.OnReceiveMessage += OnReceiveMessageHandler;

               Debug.WriteLine($"{DateTime.UtcNow:hh:mm:ss} Region {Region}");
               result = device.Region(Region);
               if (result != Result.Success)
               {
                  Debug.WriteLine($"Region failed {result}");
                  return;
               }

               Debug.WriteLine($"{DateTime.UtcNow:hh:mm:ss} ADR On");
               result = device.AdrOn();
               if (result != Result.Success)
               {
                  Debug.WriteLine($"ADR on failed {result}");
                  return;
               }

#if CONFIRMED
               Debug.WriteLine($"{DateTime.UtcNow:hh:mm:ss} Confirmed");
               result = device.Confirm(LoRaConfirmType.Confirmed);
               if (result != Result.Success)
               {
                  Debug.WriteLine($"Confirm on failed {result}");
                  return;
               }
#else
               Debug.WriteLine($"{DateTime.UtcNow:hh:mm:ss} Unconfirmed");
               result = device.Confirm(LoRaConfirmType.Unconfirmed);
               if (result != Result.Success)
               {
                  Debug.WriteLine($"Confirm off failed {result}");
                  return;
               }
#endif

#if OTAA
               Debug.WriteLine($"{DateTime.UtcNow:hh:mm:ss} OTAA");
               result = device.OtaaInitialise(DevEui, AppEui, AppKey);
               if (result != Result.Success)
               {
                  Debug.WriteLine($"OTAA Initialise failed {result}");
                  return;
               }
#endif

#if ABP
               Debug.WriteLine($"{DateTime.UtcNow:hh:mm:ss} ABP");
               result = device.AbpInitialise(DevAddress, NwksKey, AppsKey);
               if (result != Result.Success)
               {
                  Debug.WriteLine($"ABP Initialise failed {result}");
                  return;
               }
#endif

               //Debug.WriteLine($"{DateTime.UtcNow:hh:mm:ss} Join start Timeout:{JoinTimeOut:hh:mm:ss}");
               result = device.Join(JoinTimeOut);
               if (result != Result.Success)
               {
                  Debug.WriteLine($"Join failed {result}");
                  return;
               }
               Debug.WriteLine($"{DateTime.UtcNow:hh:mm:ss} Join finish");

               while (true)
               {
#if PAYLOAD_BCD
                  Debug.WriteLine($"{DateTime.UtcNow:hh:mm:ss} port:{MessagePort} payload BCD:{PayloadBcd}");
                  result = device.Send(MessagePort, PayloadBcd, SendTimeout);
#endif
#if PAYLOAD_BYTES
                  Debug.WriteLine($"{DateTime.UtcNow:hh:mm:ss} Send Timeout:{SendTimeout:hh:mm:ss} port:{MessagePort} payload Bytes:{BitConverter.ToString(PayloadBytes)}");
                  result = device.Send(MessagePort, PayloadBytes, SendTimeout);
#endif
                  if (result != Result.Success)
                  {
                     Debug.WriteLine($"Send failed {result}");
                  }

                  // if we sleep module too soon response is missed
                  Thread.Sleep(5000);

                  Debug.WriteLine($"{DateTime.UtcNow:hh:mm:ss} Sleep");
                  result = device.Sleep();
                  if (result != Result.Success)
                  {
                     Debug.WriteLine($"Sleep failed {result}");
                     return;
                  }

                  Thread.Sleep(30000);

                  Debug.WriteLine($"{DateTime.UtcNow:hh:mm:ss} Wakeup");
                  result = device.Wakeup();
                  if (result != Result.Success)
                  {
                     Debug.WriteLine($"Wakeup failed {result}");
                     return;
                  }
               }
            }
         }
         catch (Exception ex)
         {
            Debug.WriteLine(ex.Message);
         }
      }

      static void OnMessageConfirmationHandler(int rssi, int snr)
      {
         Debug.WriteLine($"{DateTime.UtcNow:hh:mm:ss} Send Confirm RSSI:{rssi} SNR:{snr}");
      }

      static void OnReceiveMessageHandler(int port, int rssi, int snr, string payloadBcd)
      {
         byte[] payloadBytes = Rak811LoRaWanDevice.BcdToByes(payloadBcd);

         Debug.WriteLine($"{DateTime.UtcNow:hh:mm:ss} Receive Message RSSI:{rssi} SNR:{snr} Port:{port} Payload:{payloadBcd} PayLoadBytes:{BitConverter.ToString(payloadBytes)}");
      }
   }
}

I noticed (mid July 2020) that when changing from from ABP to OTAA and vice versa I needed to reset the the device “frame counters” in the Things Network console.

TinyCLR OS V2 RC1 RAK811 LoRaWAN library Part2

Nasty OTAA connect

After getting basic connectivity for my RAK811 LPWAN Evaluation Board(EVB) and Fezduino test rig working. I wanted to see if I could get the device connected to The Things Network(TTN) via the RAK7246G LPWAN Developer Gateway on my desk. I had got the EVB configuration sorted with a nanoFramework device so I was confident it should work.

EVB plugged into Fezduino

My Over the Air Activation (OTAA) implementation is very “nasty” I assumed that there would be no timeouts or failures and I only send one BCD message “48656c6c6f204c6f526157414e” which is “hello LoRaWAN”

I configured the RAK811 module for LoRaWAN

// Set the Working mode to LoRaWAN
txByteCount = serialDevice.Write(UTF8Encoding.UTF8.GetBytes("at+set_config=lora:work_mode:0\r\n"));
Debug.WriteLine($"TX: work mode {txByteCount} bytes");
Thread.Sleep(500);

// Read the response
rxByteCount = serialDevice.BytesToRead;
if (rxByteCount > 0)
{
   byte[] rxBuffer = new byte[rxByteCount];
   serialDevice.Read(rxBuffer);
   Debug.WriteLine($"RX :{UTF8Encoding.UTF8.GetString(rxBuffer)}");
}
...

Then just sequentially step through the necessary configuration to join the TTN network with a suitable delay after each command is sent.

// Set the Region to AS923
txByteCount = serialDevice.Write(UTF8Encoding.UTF8.GetBytes("at+set_config=lora:region:AS923\r\n"));
Debug.WriteLine($"TX: region {txByteCount} bytes");
Thread.Sleep(500);

// Read the response
rxByteCount = serialDevice.BytesToRead;
if (rxByteCount > 0)
{
   byte[] rxBuffer = new byte[rxByteCount];
   serialDevice.Read(rxBuffer);
   Debug.WriteLine($"RX :{UTF8Encoding.UTF8.GetString(rxBuffer)}");
}

// Set the JoinMode
txByteCount = serialDevice.Write(UTF8Encoding.UTF8.GetBytes("at+set_config=lora:join_mode:0\r\n"));
Debug.WriteLine($"TX: join_mode {txByteCount} bytes");
Thread.Sleep(500);

// Read the response
rxByteCount = serialDevice.BytesToRead;
if (rxByteCount > 0)
{
   byte[] rxBuffer = new byte[rxByteCount];
   serialDevice.Read(rxBuffer);
   Debug.WriteLine($"RX :{UTF8Encoding.UTF8.GetString(rxBuffer)}");
}

// OTAA set the devEUI
txByteCount = serialDevice.Write(UTF8Encoding.UTF8.GetBytes($"at+set_config=lora:dev_eui:{DevEui}\r\n"));
Debug.WriteLine($"TX: dev_eui: {txByteCount} bytes");
Thread.Sleep(500);

// Read the response
rxByteCount = serialDevice.BytesToRead;
if (rxByteCount > 0)
{
   byte[] rxBuffer = new byte[rxByteCount];
   serialDevice.Read(rxBuffer);
   Debug.WriteLine($"RX :{UTF8Encoding.UTF8.GetString(rxBuffer)}");
}
...

The code is not suitable for production but it confirmed my software and hardware configuration worked.

The thread '<No Name>' (0x2) has exited with code 0 (0x0).
devMobile.IoT.Rak811.NetworkJoinOTAA starting
TX: work mode 32 bytes
RX :UART1 work mode: RUI_UART_NORAMAL
Current work_mode:LoRaWAN, join_mode:OTAA, Class: A
Initialization OK 

TX: region 33 bytes
RX :OK 

TX: join_mode 32 bytes
RX :OK 

TX: dev_eui: 45 bytes
RX :OK 

TX: app_eui 45 bytes
RX :OK 

TX: app_key 61 bytes
RX :OK 

TX: confirm 30 bytes
RX :OK 

TX: join 9 bytes
RX :OK Join Success

TX: send 43 bytes
RX :OK 

TX: send 43 bytes
RX :OK 

In the Visual Studio 2019 debug output I could see messages getting sent and then after a short delay they were visible in the TTN console.

Successful OTAA Connect TTN logging

I had some issues with TimeSpan.ToString(…) throwing a CLR_E_UNSUPPORTED_INSTRUCTION exception which has been mentioned on the GHI Forums.

I had to modify my code to fix this issue

Debug.WriteLine($"{DateTime.UtcNow:hh:mm:ss} Join start Timeout:{JoinTimeOut:hh:mm:ss}");

// Became

Debug.WriteLine($" {DateTime.UtcNow:hh:mm:ss} Join Start Timeout {timeout.TotalSeconds} seconds");

I won’t bother with confirming any other functionality as I’m reasonably confident the nanoFramework library (which this code is based on) is working as expected.

TinyCLR OS V2 RC1 RAK811 LoRaWAN library Part1

Basic connectivity

Over the weekend I have been working on a GHI Electronics TinyCLR V2  C# library for my modified RAK811 LPWAN Evaluation Board(EVB) from RAK Wireless. My initial test rig is based on an Fezduino board which has Arduino Uno R3 format socket for the EVB.

Fezduino with RAK Wisnode shield

The code has compile time options for synchronous and asynchronous operation.

   public class Program
   {
      private static UartController serialDevice;
      private const string ATCommand = "at+version\r\n";
#if TINYCLR_V2_FEZDUINO
      private static string SerialPortId = SC20100.UartPort.Uart5;
#endif

      public static void Main()
      {
         Debug.WriteLine("devMobile.IoT.Rak811.ShieldSerial starting");

         try
         {
            serialDevice = UartController.FromName(SerialPortId);

            serialDevice.SetActiveSettings(new UartSetting()
            {
               BaudRate = 9600,
               Parity = UartParity.None,
               StopBits = UartStopBitCount.One,
               Handshaking = UartHandshake.None,
               DataBits = 8
            });

            serialDevice.Enable();

#if SERIAL_ASYNC_READ
            serialDevice.DataReceived += SerialDevice_DataReceived;
#endif

            while (true)
            {
               byte[] txBuffer = UTF8Encoding.UTF8.GetBytes(ATCommand);

               int txByteCount = serialDevice.Write(txBuffer);
               Debug.WriteLine($"TX: {txByteCount} bytes");

#if SERIAL_SYNC_READ
               while( serialDevice.BytesToWrite>0)
               {
                  Debug.WriteLine($" BytesToWrite {serialDevice.BytesToWrite}");
                  Thread.Sleep(100);
               }

               int rxByteCount = serialDevice.BytesToRead;
               if (rxByteCount>0)
               {
                  byte[] rxBuffer = new byte[rxByteCount];

                  serialDevice.Read(rxBuffer);

                  Debug.WriteLine($"RX sync:{rxByteCount} bytes read");
                  String response = UTF8Encoding.UTF8.GetString(rxBuffer);
                  Debug.WriteLine($"RX sync:{response}");
               }
#endif

               Thread.Sleep(20000);
            }
         }
         catch (Exception ex)
         {
            Debug.WriteLine(ex.Message);
         }
      }


#if SERIAL_ASYNC_READ
      private static void SerialDevice_DataReceived(UartController sender, DataReceivedEventArgs e)
      {
         byte[] rxBuffer = new byte[e.Count];

         serialDevice.Read(rxBuffer, 0, e.Count);

         Debug.WriteLine($"RX Async:{e.Count} bytes read");
         String response = UTF8Encoding.UTF8.GetString(rxBuffer);
         Debug.WriteLine($"RX Async:{response}");
      }
#endif
   }

When I first ran the code I noticed the serialDevice.Read timed out before any characters were received.

The thread '<No Name>' (0x2) has exited with code 0 (0x0).
devMobile.IoT.Rak811.ShieldSerial starting
TX: 12 bytes
TX: 12 bytes
RX sync:19 bytes read
RX sync:OK V3.0.0.13.H.T3

TX: 12 bytes
RX sync:19 bytes read
RX sync:OK V3.0.0.13.H.T3

TX: 12 bytes
RX sync:19 bytes read
RX sync:OK V3.0.0.13.H.T3

I then added code to check the message had been sent and the code worked as expected. I now think, that rather than checking that the characters had been sent the short 100mSec delay was more important.

The thread '<No Name>' (0x2) has exited with code 0 (0x0).
devMobile.IoT.Rak811.ShieldSerial starting
TX: 12 bytes
 BytesToWrite 10
RX sync:19 bytes read
RX sync:OK V3.0.0.13.H.T3

TX: 12 bytes
 BytesToWrite 10
RX sync:19 bytes read
RX sync:OK V3.0.0.13.H.T3

TX: 12 bytes
 BytesToWrite 10
RX sync:19 bytes read
RX sync:OK V3.0.0.13.H.T3

I then added code to receive data asynchronously and the response to the version request was received as expected.

The thread '<No Name>' (0x2) has exited with code 0 (0x0).
devMobile.IoT.Rak811.ShieldSerial starting
TX: 12 bytes
RX Async:1 bytes read
RX Async:O
RX Async:8 bytes read
RX Async:K V3.0.0
RX Async:10 bytes read
RX Async:.13.H.T3

TX: 12 bytes
RX Async:1 bytes read
RX Async:O
RX Async:5 bytes read
RX Async:K V3.
RX Async:9 bytes read
RX Async:0.0.13.H.
RX Async:4 bytes read
RX Async:T3

RFM9X.TinyCLR V2 RC1 on Github

The source code of my GHI Electronics TinyCLR-0SV2RC1 RFM9X/SX127X library is live on GitHub. The test harness uses a Fezduino and a dragino technology LoRa shield for Arduino. I will add FezPortal, FezFeather and Fezstick support soon.

Fezduino with Dragino shield

A sample application which shows how to send/receive address/un-addresses payloads

//---------------------------------------------------------------------------------
// Copyright (c) March/April 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.
//
// Need one of TINYCLR_V2_SC20100DEV/TINYCLR_V2_FEZDUINO defined
//---------------------------------------------------------------------------------
namespace devMobile.IoT.Rfm9x.LoRaDeviceClient
{
	using System;
	using System.Diagnostics;
	using System.Text;
	using System.Threading;

	using GHIElectronics.TinyCLR.Pins;

	using devMobile.IoT.Rfm9x;

	class Program
   {
      static void Main()
      {
#if TINYCLR_V2_SC20100DEV
			const string DeviceName = "SC20100DEVLoRa";
#endif
#if TINYCLR_V2_FEZDUINO
			const string DeviceName = "FezduinoLoRa";
#endif
#if ADDRESSED_MESSAGES_PAYLOAD
			const string HostName = "LoRaIoT1";
#endif
			const double Frequency = 915000000.0;
			byte MessageCount = System.Byte.MaxValue;
#if TINYCLR_V2_SC20100DEV
         Rfm9XDevice rfm9XDevice = new Rfm9XDevice(SC20100.SpiBus.Spi3, SC20100.GpioPin.PA13, SC20100.GpioPin.PA14, SC20100.GpioPin.PE4);
#endif
#if TINYCLR_V2_FEZDUINO
         Rfm9XDevice rfm9XDevice = new Rfm9XDevice(SC20100.SpiBus.Spi6, SC20100.GpioPin.PB1, SC20100.GpioPin.PA15, SC20100.GpioPin.PA1);
#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);
				Debug.WriteLine($"{DateTime.Now:HH:mm:ss}-TX {messageBytes.Length} byte message {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
			{
				string messageText = UTF8Encoding.UTF8.GetString(e.Data);

#if ADDRESSED_MESSAGES_PAYLOAD
				string addressText = UTF8Encoding.UTF8.GetString(e.Address);

				Debug.WriteLine($@"{DateTime.Now:HH:mm:ss}-RX From {addressText} PacketSnr {e.PacketSnr} Packet RSSI {e.PacketRssi}dBm RSSI {e.Rssi}dBm = {e.Data.Length} byte message ""{messageText}""");
#else
				Debug.WriteLine($@"{DateTime.Now:HH:mm:ss}-RX PacketSnr {e.PacketSnr} Packet RSSI {e.PacketRssi}dBm RSSI {e.Rssi}dBm = {e.Data.Length} byte message ""{messageText}""");
#endif
			}
			catch (Exception ex)
			{
				Debug.WriteLine(ex.Message);
			}
		}

		private static void Rfm9XDevice_OnTransmit(object sender, Rfm9XDevice.OnDataTransmitedEventArgs e)
		{
			Debug.WriteLine($"{DateTime.Now:HH:mm:ss}-TX Done");
		}
	}
}

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 late beta.

TinyCLR OS V2 RC1 LoRa library Part3

Why are Transmit Interrupts broken?

The receive using interrupts appeared to be working but transmit with interrupts I could only send a couple of messages before confirmations stopped.

I had read about restrictions for interrupts pins e.g. PA1 & PB1 can’t be used at the same time, but PA1 and PB2 can, which got me thinking…

In my dragino shield based setup Arduino D2(PA1) is the interrupt(IRQ) line and Arduino D10(PB1) is chip select (CS) so I changed the pins with jumper wires just incase.

Fezduino connected to Dragino LoRa shield with jumpers

I tried several different configurations of CS and IRQ pins and none worked.

On other embedded .net platforms I have written Serial Peripheral Interface(SPI) based drivers for (e.g. Wilderness Labs Meadow and the nanoFramework) there had been issues with the use of device.Write vs. device. TransferFullDuplex (or its equivalent).

The RegisterWriteByte method in the event handler appeared to be the problem so I tried modifying it.

public void RegisterWriteByte(byte address, byte value)
{
   byte[] writeBuffer = new byte[] { address |= RegisterAddressWriteMask, value };
   Debug.Assert(rfm9XLoraModem != null);

   rfm9XLoraModem.Write(writeBuffer);
}

Became

public void RegisterWriteByte(byte address, byte value)
{
   byte[] writeBuffer = new byte[] { address |= RegisterAddressWriteMask, value };
   byte[] readBuffer = new byte[2];
   Debug.Assert(rfm9XLoraModem != null);

   rfm9XLoraModem.TransferFullDuplex(writeBuffer, readBuffer);
}

In the diagnostic output I could see confirmations arriving

The thread '<No Name>' (0x2) has exited with code 0 (0x0).
Sending 13 bytes message Hello LoRa 1!
RegIrqFlags 0X08
Transmit-Done
Sending 13 bytes message Hello LoRa 2!
RegIrqFlags 0X08
Transmit-Done
Sending 13 bytes message Hello LoRa 3!
RegIrqFlags 0X08
Transmit-Done
Sending 13 bytes message Hello LoRa 4!
RegIrqFlags 0X08
Transmit-Done
Sending 13 bytes message Hello LoRa 5!
RegIrqFlags 0X08
Transmit-Done
Sending 13 bytes message Hello LoRa 6!
RegIrqFlags 0X08
Transmit-Done

This was clue it might be a timing problem, so I took a closer look at how the SPI port was configured. After some experimentation I found that by adding a small ChipSelectHoldTime the .Write statements worked.

When I went back and checked there had also been some timing “tweaks” required to get my .Net Microframework LoRa library to work reliably.

public Rfm9XDevice(string spiPortName, int chipSelectPin, int resetPin, int interruptPin)
{
   GpioController gpioController = GpioController.GetDefault();

   GpioPin chipSelectGpio = gpioController.OpenPin(chipSelectPin);

   var settings = new SpiConnectionSettings()
   {
      ChipSelectType = SpiChipSelectType.Gpio,
      ChipSelectLine = chipSelectGpio,
      Mode = SpiMode.Mode0,
      ClockFrequency = 500000,
      ChipSelectActiveState = false,
      //ChipSelectHoldTime = new TimeSpan(50),
      //ChipSelectHoldTime = new TimeSpan(25),
      //ChipSelectHoldTime = new TimeSpan(10),
      ChipSelectHoldTime = new TimeSpan(5),
      //ChipSelectHoldTime = new TimeSpan(1),
   };

   SpiController spiController = SpiController.FromName(spiPortName);

   rfm9XLoraModem = spiController.GetDevice(settings);

   // Factory reset pin configuration
   GpioPin resetGpioPin = gpioController.OpenPin(resetPin);
   resetGpioPin.SetDriveMode(GpioPinDriveMode.Output);
   resetGpioPin.Write(GpioPinValue.Low);
   Thread.Sleep(10);
   resetGpioPin.Write(GpioPinValue.High);
   Thread.Sleep(10);

   // Interrupt pin for RX message & TX done notification 
   InterruptGpioPin = gpioController.OpenPin(interruptPin);
   InterruptGpioPin.SetDriveMode(GpioPinDriveMode.Input);

   InterruptGpioPin.ValueChanged += InterruptGpioPin_ValueChanged;
}

In the diagnostic output I could see confirmations arriving

...
Sending 16 bytes message Hello LoRa 1115!
RegIrqFlags 0X08
Transmit-Done
Sending 16 bytes message Hello LoRa 1116!
RegIrqFlags 0X08
Transmit-Done
Sending 16 bytes message Hello LoRa 1117!
RegIrqFlags 0X08
Transmit-Done
Sending 16 bytes message Hello LoRa 1118!
RegIrqFlags 0X08
Transmit-Done
Sending 16 bytes message Hello LoRa 1119!
RegIrqFlags 0X08
Transmit-Done
Sending 16 bytes message Hello LoRa 1120!
RegIrqFlags 0X08
Transmit-Done
Sending 16 bytes message Hello LoRa 1121!
RegIrqFlags 0X08
Transmit-Done
Sending 16 bytes message Hello LoRa 1122!
RegIrqFlags 0X08
The program '[13] TinyCLR application: Managed' has exited with code 0 (0x0).

After some soak testing it looks like the ChipSelectHoldTime modification works pretty reliably but I will need watch for issues.

EDIT: After a long walk I have updated the code to use TransferFullDuplex rather than add a ChipSelectHoldTime.

TinyCLR OS V2 RC1 LoRa library Part2

Receive and Transmit

The first step was to confirm the transmission of messages with polled completion confirmation was working as expected.

   class Program
   {
      static void Main()
      {
#if TINYCLR_V2_SC20100DEV
         Rfm9XDevice rfm9XDevice = new Rfm9XDevice(SC20100.SpiBus.Spi3, SC20100.GpioPin.PA13, SC20100.GpioPin.PA14);
#endif
#if TINYCLR_V2_FEZDUINO
         Rfm9XDevice rfm9XDevice = new Rfm9XDevice(SC20100.SpiBus.Spi6, SC20100.GpioPin.PB1, SC20100.GpioPin.PA15);
#endif
         int SendCount = 0;

         // Put device into LoRa + Sleep mode
         rfm9XDevice.RegisterWriteByte(0x01, 0b10000000); // RegOpMode 

         // Set the frequency to 915MHz
         byte[] frequencyWriteBytes = { 0xE4, 0xC0, 0x00 }; // RegFrMsb, RegFrMid, RegFrLsb
         rfm9XDevice.RegisterWrite(0x06, frequencyWriteBytes);

         // More power PA Boost
         rfm9XDevice.RegisterWriteByte(0x09, 0b10000000); // RegPaConfig

         rfm9XDevice.RegisterDump();

         while (true)
         {
            rfm9XDevice.RegisterWriteByte(0x0E, 0x0); // RegFifoTxBaseAddress 

            // Set the Register Fifo address pointer
            rfm9XDevice.RegisterWriteByte(0x0D, 0x0); // RegFifoAddrPtr 

            string messageText = $"Hello LoRa {SendCount += 1}!";
               
            // load the message into the fifo
            byte[] messageBytes = UTF8Encoding.UTF8.GetBytes(messageText);
            rfm9XDevice.RegisterWrite(0x0, messageBytes); // RegFifo

            // Set the length of the message in the fifo
            rfm9XDevice.RegisterWriteByte(0x22, (byte)messageBytes.Length); // RegPayloadLength

            Debug.WriteLine($"Sending {messageBytes.Length} bytes message {messageText}");
            /// Set the mode to LoRa + Transmit
            rfm9XDevice.RegisterWriteByte(0x01, 0b10000011); // RegOpMode 

            // Wait until send done, no timeouts in PoC
            Debug.WriteLine("Send-wait");
            byte IrqFlags = rfm9XDevice.RegisterReadByte(0x12); // RegIrqFlags
            while ((IrqFlags & 0b00001000) == 0)  // wait until TxDone cleared
            {
               Thread.Sleep(10);
               IrqFlags = rfm9XDevice.RegisterReadByte(0x12); // RegIrqFlags
               Debug.WriteLine(".");
            }
            rfm9XDevice.RegisterWriteByte(0x12, 0b00001000); // clear TxDone bit
            Debug.WriteLine("Send-Done");

            Thread.Sleep(30000);
         }
      }
   }

The diagnostic output shows messages being sent and on another device I could see the messages arriving. I do wonder why the first message often takes so long to send?

Register dump
Register 0x00 - Value 0Xc3
Register 0x01 - Value 0X80
Register 0x02 - Value 0X1a
Register 0x03 - Value 0X0b
Register 0x04 - Value 0X00
Register 0x05 - Value 0X52
Register 0x06 - Value 0Xe4
Register 0x07 - Value 0Xc0
Register 0x08 - Value 0X00
Register 0x09 - Value 0X80
Register 0x0a - Value 0X09
Register 0x0b - Value 0X2b
Register 0x0c - Value 0X20
Register 0x0d - Value 0X01
Register 0x0e - Value 0X80
Register 0x0f - Value 0X00
Register 0x10 - Value 0X00
Register 0x11 - Value 0X00
Register 0x12 - Value 0X00
Register 0x13 - Value 0X00
Register 0x14 - Value 0X00
Register 0x15 - Value 0X00
Register 0x16 - Value 0X00
Register 0x17 - Value 0X00
Register 0x18 - Value 0X10
Register 0x19 - Value 0X00
Register 0x1a - Value 0X00
Register 0x1b - Value 0X00
Register 0x1c - Value 0X00
Register 0x1d - Value 0X72
Register 0x1e - Value 0X70
Register 0x1f - Value 0X64
Register 0x20 - Value 0X00
Register 0x21 - Value 0X08
Register 0x22 - Value 0X01
Register 0x23 - Value 0Xff
Register 0x24 - Value 0X00
Register 0x25 - Value 0X00
Register 0x26 - Value 0X04
Register 0x27 - Value 0X00
Register 0x28 - Value 0X00
Register 0x29 - Value 0X00
Register 0x2a - Value 0X00
Register 0x2b - Value 0X00
Register 0x2c - Value 0X00
Register 0x2d - Value 0X50
Register 0x2e - Value 0X14
Register 0x2f - Value 0X45
Register 0x30 - Value 0X55
Register 0x31 - Value 0Xc3
Register 0x32 - Value 0X05
Register 0x33 - Value 0X27
Register 0x34 - Value 0X1c
Register 0x35 - Value 0X0a
Register 0x36 - Value 0X03
Register 0x37 - Value 0X0a
Register 0x38 - Value 0X42
Register 0x39 - Value 0X12
Register 0x3a - Value 0X49
Register 0x3b - Value 0X1d
Register 0x3c - Value 0X00
Register 0x3d - Value 0Xaf
Register 0x3e - Value 0X00
Register 0x3f - Value 0X00
Register 0x40 - Value 0X00
Register 0x41 - Value 0X00
Register 0x42 - Value 0X12
Sending 13 bytes message Hello LoRa 1!
Send-wait
.
.
.
.
.
Send-Done
Sending 13 bytes message Hello LoRa 2!
Send-wait
Send-Done
Sending 13 bytes message Hello LoRa 3!
Send-wait
Send-Done
Sending 13 bytes message Hello LoRa 4!
Send-wait
Send-Done
Sending 13 bytes message Hello LoRa 5!
Send-wait
Send-Done
Sending 13 bytes message Hello LoRa 6!
Send-wait
Send-Done

The second step was to confirm the polled reception of messages was working as expected.

   class Program
   {
      static void Main()
      {
#if TINYCLR_V2_SC20100DEV
         Rfm9XDevice rfm9XDevice = new Rfm9XDevice(SC20100.SpiBus.Spi3, SC20100.GpioPin.PA13, SC20100.GpioPin.PA14);
#endif
#if TINYCLR_V2_FEZDUINO
         Rfm9XDevice rfm9XDevice = new Rfm9XDevice(SC20100.SpiBus.Spi6, SC20100.GpioPin.PB1, SC20100.GpioPin.PA15);
#endif


         // Put device into LoRa + Sleep mode
         rfm9XDevice.RegisterWriteByte(0x01, 0b10000000); // RegOpMode 

         // Set the frequency to 915MHz
         byte[] frequencyWriteBytes = { 0xE4, 0xC0, 0x00 }; // RegFrMsb, RegFrMid, RegFrLsb
         rfm9XDevice.RegisterWrite(0x06, frequencyWriteBytes);

         rfm9XDevice.RegisterWriteByte(0x0F, 0x0); // RegFifoRxBaseAddress 

         rfm9XDevice.RegisterWriteByte(0x01, 0b10000101); // RegOpMode set LoRa & RxContinuous

         while (true)
         {
            // Wait until a packet is received, no timeouts in PoC
            Debug.WriteLine("Receive-Wait");
            byte irqFlags = rfm9XDevice.RegisterReadByte(0x12); // RegIrqFlags
            while ((irqFlags & 0b01000000) == 0)  // wait until RxDone cleared
            {
               Thread.Sleep(100);
               irqFlags = rfm9XDevice.RegisterReadByte(0x12); // RegIrqFlags
               //Debug.Write(".");
            }
            Debug.WriteLine("");
            Debug.WriteLine($"RegIrqFlags 0X{irqFlags:X2}");
            Debug.WriteLine("Receive-Message");
            byte currentFifoAddress = rfm9XDevice.RegisterReadByte(0x10); // RegFifiRxCurrent
            rfm9XDevice.RegisterWriteByte(0x0d, currentFifoAddress); // RegFifoAddrPtr

            byte numberOfBytes = rfm9XDevice.RegisterReadByte(0x13); // RegRxNbBytes

            byte[] messageBytes = rfm9XDevice.RegisterRead(0x00, numberOfBytes); // RegFifo

            rfm9XDevice.RegisterWriteByte(0x0d, 0);
            rfm9XDevice.RegisterWriteByte(0x12, 0b11111111); // RegIrqFlags clear all the bits

            string messageText = UTF8Encoding.UTF8.GetString(messageBytes);
            Debug.WriteLine($"Received {messageBytes.Length} byte message {messageText}");

            Debug.WriteLine("Receive-Done");
         }
      }
   }

The diagnostic output shows messages being received from one of my other devices.

The thread ” (0x2) has exited with code 0 (0x0).
Receive-Wait

RegIrqFlags 0X50
Receive-Message
Received 23 byte message �LoRaIoT1N3WT 18.8,H 78
Receive-Done
Receive-Wait

RegIrqFlags 0X50
Receive-Message
Received 23 byte message �LoRaIoT1N3WT 18.8,H 78
Receive-Done
Receive-Wait

The next step was to confirm the interrupt driven reception of messages was working as expected.

   class Program
   {
      static void Main()
      {
#if TINYCLR_V2_SC20100DEV
         Rfm9XDevice rfm9XDevice = new Rfm9XDevice(SC20100.SpiBus.Spi3, SC20100.GpioPin.PA13, SC20100.GpioPin.PA14, SC20100.GpioPin.PE4);
#endif
#if TINYCLR_V2_FEZDUINO
         Rfm9XDevice rfm9XDevice = new Rfm9XDevice(SC20100.SpiBus.Spi6, SC20100.GpioPin.PB1, SC20100.GpioPin.PA15, SC20100.GpioPin.PA1);
#endif

         // Put device into LoRa + Sleep mode
         rfm9XDevice.RegisterWriteByte(0x01, 0b10000000); // RegOpMode 

         // Set the frequency to 915MHz
         byte[] frequencyWriteBytes = { 0xE4, 0xC0, 0x00 }; // RegFrMsb, RegFrMid, RegFrLsb
         rfm9XDevice.RegisterWrite(0x06, frequencyWriteBytes);

         rfm9XDevice.RegisterWriteByte(0x0F, 0x0); // RegFifoRxBaseAddress 

         rfm9XDevice.RegisterWriteByte(0x40, 0b00000000); // RegDioMapping1 0b00000000 DI0 RxReady & TxReady

         rfm9XDevice.RegisterWriteByte(0x01, 0b10000101); // RegOpMode set LoRa & RxContinuous

         rfm9XDevice.RegisterDump();

         Debug.WriteLine("Receive-Wait");
         Thread.Sleep(Timeout.Infinite);
      }
   }

      private void InterruptGpioPin_ValueChanged(GpioPin sender, GpioPinValueChangedEventArgs e)
      {
         if (e.Edge != GpioPinEdge.RisingEdge)
         {
            return;
         }

         byte irqFlags = this.RegisterReadByte(0x12); // RegIrqFlags
         Debug.WriteLine($"RegIrqFlags 0X{irqFlags:x2}");
         if ((irqFlags & 0b01000000) == 0b01000000)  // RxDone 
         {
            Debug.WriteLine("Receive-Message");
            byte currentFifoAddress = this.RegisterReadByte(0x10); // RegFifiRxCurrent
            this.RegisterWriteByte(0x0d, currentFifoAddress); // RegFifoAddrPtr

            byte numberOfBytes = this.RegisterReadByte(0x13); // RegRxNbBytes

            // Get number of bytes in the message
            byte[] messageBytes = this.RegisterRead(0x00, numberOfBytes);

            string messageText = UTF8Encoding.UTF8.GetString(messageBytes);
            Debug.WriteLine($"Received {messageBytes.Length} byte message {messageText}");
         }

         this.RegisterWriteByte(0x12, 0xff);// RegIrqFlags
      }

The diagnostic output shows messages being received from one of my other devices.

The thread '<No Name>' (0x2) has exited with code 0 (0x0).
Receive-Wait
RegIrqFlags 0X50
Receive-Message
Received 23 byte message  �LoRaIoT1N3WT 18.8,H 78
RegIrqFlags 0X50
Receive-Message
Received 23 byte message  �LoRaIoT1N3WT 18.7,H 79

The final step was to confirm the interrupt driven transmission of messages was working as expected.

   class Program
   {
      static void Main()
      {
#if TINYCLR_V2_SC20100DEV
         Rfm9XDevice rfm9XDevice = new Rfm9XDevice(SC20100.SpiBus.Spi3, SC20100.GpioPin.PA13, SC20100.GpioPin.PA14, SC20100.GpioPin.PE4);
#endif
#if TINYCLR_V2_FEZDUINO
         Rfm9XDevice rfm9XDevice = new Rfm9XDevice(SC20100.SpiBus.Spi6, SC20100.GpioPin.PB1, SC20100.GpioPin.PA15, SC20100.GpioPin.PA1); // Doesn't work
#endif
         int SendCount = 0;

         // Put device into LoRa + Sleep mode
         rfm9XDevice.RegisterWriteByte(0x01, 0b10000000); // RegOpMode 

         // Set the frequency to 915MHz
         byte[] frequencyWriteBytes = { 0xE4, 0xC0, 0x00 }; // RegFrMsb, RegFrMid, RegFrLsb
         rfm9XDevice.RegisterWrite(0x06, frequencyWriteBytes);

         // More power PA Boost
         rfm9XDevice.RegisterWriteByte(0x09, 0b10000000); // RegPaConfig

         // Interrupt on TxDone
         rfm9XDevice.RegisterWriteByte(0x40, 0b01000000); // RegDioMapping1 0b00000000 DI0 TxDone

         while (true)
         {
            // Set the Register Fifo address pointer
            rfm9XDevice.RegisterWriteByte(0x0E, 0x00); // RegFifoTxBaseAddress 

            // Set the Register Fifo address pointer
            rfm9XDevice.RegisterWriteByte(0x0D, 0x0); // RegFifoAddrPtr 

            string messageText = $"Hello LoRa {SendCount += 1}!";

            // load the message into the fifo
            byte[] messageBytes = UTF8Encoding.UTF8.GetBytes(messageText);
            rfm9XDevice.RegisterWrite(0x0, messageBytes); // RegFifo 

            // Set the length of the message in the fifo
            rfm9XDevice.RegisterWriteByte(0x22, (byte)messageBytes.Length); // RegPayloadLength
            Debug.WriteLine($"Sending {messageBytes.Length} bytes message {messageText}");
            rfm9XDevice.RegisterWriteByte(0x01, 0b10000011); // RegOpMode 

            Thread.Sleep(10000);
         }
      }
   }


private void InterruptGpioPin_ValueChanged(GpioPin sender, GpioPinValueChangedEventArgs e)
      {
         if (e.Edge != GpioPinEdge.RisingEdge)
         {
            return;
         }

         byte irqFlags = this.RegisterReadByte(0x12); // RegIrqFlags
         Debug.WriteLine($"RegIrqFlags 0X{irqFlags:x2}");

         if ((irqFlags & 0b00001000) == 0b00001000)  // TxDone
         {
            Debug.WriteLine("Transmit-Done");
         }

         this.RegisterWriteByte(0x12, 0xff);// RegIrqFlags
      }

The diagnostic output shows messages being sent but after the first message (sometimes the second or third) there are no confirmations.

The thread ” (0x2) has exited with code 0 (0x0).
Sending 13 bytes message Hello LoRa 1!
RegIrqFlags 0X08
Transmit-Done
Sending 13 bytes message Hello LoRa 2!
Sending 13 bytes message Hello LoRa 3!
Sending 13 bytes message Hello LoRa 4!
Sending 13 bytes message Hello LoRa 5!
Sending 13 bytes message Hello LoRa 6!
Sending 13 bytes message Hello LoRa 7!
Sending 13 bytes message Hello LoRa 8!
Sending 13 bytes message Hello LoRa 9!
Sending 14 bytes message Hello LoRa 10!
Sending 14 bytes message Hello LoRa 11!
Sending 14 bytes message Hello LoRa 12!
Sending 14 bytes message Hello LoRa 13!
Sending 14 bytes message Hello LoRa 14!

It looks like something has been broken (possibly by RC1) in my implementation of interrupt driven transmission of messages.