Netduino LoRa Radio 433/868/915 MHz Payload Addressing client

This is a demo Netduino client (based on one of the examples in my RFM9XLoRaNetMF library) that uploads telemetry data to my Windows 10 IoT Core on Raspberry PI field gateway proof of concept(PoC).

Bill of materials (Prices Sep 2018)

//---------------------------------------------------------------------------------
// Copyright (c) 2017, 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.
//---------------------------------------------------------------------------------
namespace devMobile.IoT.Netduino.FieldGateway
{
   using System;
   using System.Text;
   using System.Threading;
   using Microsoft.SPOT;
   using Microsoft.SPOT.Hardware;
   using SecretLabs.NETMF.Hardware.Netduino;
   using devMobile.IoT.NetMF.ISM;
   using devMobile.NetMF.Sensor;

   class NetduinoClient
   {
      Rfm9XDevice rfm9XDevice;
      private readonly TimeSpan dueTime = new TimeSpan(0, 0, 15);
      private readonly TimeSpan periodTime = new TimeSpan(0, 0, 300);
      private readonly SiliconLabsSI7005 sensor = new SiliconLabsSI7005();
      private readonly OutputPort _led = new OutputPort(Pins.ONBOARD_LED, false);
      private readonly byte[] fieldGatewayAddress = Encoding.UTF8.GetBytes("LoRaIoT1");
      private readonly byte[] deviceAddress = Encoding.UTF8.GetBytes("Netduino1");

      public NetduinoClient()
      {
         rfm9XDevice = new Rfm9XDevice(Pins.GPIO_PIN_D10, Pins.GPIO_PIN_D9, Pins.GPIO_PIN_D2);
      }

      public void Run()
      {
         //rfm9XDevice.Initialise(frequency: 915000000, paBoost: true, rxPayloadCrcOn: true);
         rfm9XDevice.Initialise(frequency: 433000000, paBoost: true, rxPayloadCrcOn: true);
         rfm9XDevice.Receive(deviceAddress);

         rfm9XDevice.OnDataReceived += rfm9XDevice_OnDataReceived;
         rfm9XDevice.OnTransmit += rfm9XDevice_OnTransmit;

         Timer humidityAndtemperatureUpdates = new Timer(HumidityAndTemperatureTimerProc, null, dueTime, periodTime);

         Thread.Sleep(Timeout.Infinite);
      }

      private void HumidityAndTemperatureTimerProc(object state)
      {
         _led.Write(true);

         double humidity = sensor.Humidity();
         double temperature = sensor.Temperature();

         Debug.Print(DateTime.UtcNow.ToString("hh:mm:ss") + " H:" + humidity.ToString("F1") + " T:" + temperature.ToString("F1"));

         rfm9XDevice.Send(fieldGatewayAddress, Encoding.UTF8.GetBytes( "t " + temperature.ToString("F1") + ",H " + humidity.ToString("F0")));

         _led.Write(true);
      }

      void rfm9XDevice_OnTransmit()
      {
         Debug.Print("Transmit-Done");
         _led.Write(false);
      }

      void rfm9XDevice_OnDataReceived(byte[] address, float packetSnr, int packetRssi, int rssi, byte[] data)
      {
         try
         {
            string messageText = new string(UTF8Encoding.UTF8.GetChars(data));
            string addressText = new string(UTF8Encoding.UTF8.GetChars(address));

            Debug.Print(DateTime.UtcNow.ToString("HH:MM:ss") + "-Rfm9X PacketSnr " + packetSnr.ToString("F1") + " Packet RSSI " + packetRssi + "dBm RSSI " + rssi + "dBm = " + data.Length + " byte message " + @"""" + messageText + @"""");
         }
         catch (Exception ex)
         {
            Debug.Print(ex.Message);
         }
      }
   }
}

The code is available on GitHub
FieldGatewayNetduinoLoRaElecrow915
Elecrow shield
FieldGatewayNetduinoLoRaDragino915
Dragino shield
FieldGatewayNetduinLoRaMakerFabs433
MakerFabs shield
Net Micro Framework debug output from device

The thread '' (0x2) has exited with code 0 (0x0).
12:00:18 H:96.9 T:19.6
Transmit-Done
12:05:17 H:95.1 T:20.1
Transmit-Done

.Net Framework debug output Field Gateway

The thread 0x1550 has exited with code 0 (0x0).
21:21:49-RX From Netduino1 PacketSnr 9.5 Packet RSSI -40dBm RSSI -107dBm = 11 byte message "t 19.6,H 97"
 Sensor Netduino1t Value 19.6
 Sensor Netduino1H Value 97
 AzureIoTHubClient SendEventAsync start
 AzureIoTHubClient SendEventAsync finish
...
21:26:49-RX From Netduino1 PacketSnr 9.5 Packet RSSI -33dBm RSSI -103dBm = 11 byte message "t 20.1,H 95"
 Sensor Netduino1t Value 20.1
 Sensor Netduino1H Value 95
 AzureIoTHubClient SendEventAsync start
 AzureIoTHubClient SendEventAsync finish
The thread 0xfbc has exited with code 0 (0x0).

Then in my Azure IoT Hub

AzureIOTHubExplorerScreenGrab20180917

Maduino LoRa Radio 868MHz Payload Addressing client

This is a demo MakerFabs Maduino LoRa Radio 868MHz client (based on one of the examples from Arduino-LoRa) that uploads telemetry data to my Windows 10 IoT Core on Raspberry PI AdaFruit.IO and Azure IoT Hub field gateways.

The code is available on Github

MaduinoLoRa86820180914

/*
  Adapted from LoRa Duplex communication with Sync Word

  Sends temperature & humidity data from Seeedstudio 

  https://www.seeedstudio.com/Grove-Temperature-Humidity-Sensor-High-Accuracy-Min-p-1921.html

  To my Windows 10 IoT Core RFM 9X library

  https://blog.devmobile.co.nz/2018/09/03/rfm9x-iotcore-payload-addressing/

*/
#include               // include libraries
#include
#include
const int csPin = 10;          // LoRa radio chip select
const int resetPin = 9;       // LoRa radio reset
const int irqPin = 2;         // change for your board; must be a hardware interrupt pin

// Field gateway configuration
const char FieldGatewayAddress[] = "LoRaIoT1";
const float FieldGatewayFrequency =  915000000.0;
//const float FieldGatewayFrequency =  433000000.0;
const byte FieldGatewaySyncWord = 0x12 ;

// Payload configuration
const int PayloadSizeMaximum = 64 ;
byte payload[PayloadSizeMaximum] = "";
const byte SensorReadingSeperator = ',' ;

// Manual serial number configuration
const char DeviceId[] = {"Maduino1"};

const int LoopSleepDelaySeconds = 10 ;

void setup() {
  Serial.begin(9600);
  while (!Serial);

  Serial.println("LoRa Setup");

  // override the default CS, reset, and IRQ pins (optional)
  LoRa.setPins(csPin, resetPin, irqPin);// set CS, reset, IRQ pin

  if (!LoRa.begin(FieldGatewayFrequency))
  {
    Serial.println("LoRa init failed. Check your connections.");
    while (true);
  }

  // Need to do this so field gateways pays attention to messsages from this device
  LoRa.enableCrc();
  LoRa.setSyncWord(FieldGatewaySyncWord);  

  //LoRa.dumpRegisters(Serial);
  Serial.println("LoRa Setup done.");

  // Configure the Seeedstudio TH02 temperature & humidity sensor
  Serial.println("TH02 setup");
  TH02.begin();
  delay(100);
  Serial.println("TH02 Setup done");  

  Serial.println("Setup done");
}

void loop()
{
  int payloadLength = 0 ;
  float temperature ;
  float humidity ;

  Serial.println("Loop called");
  memset(payload, 0, sizeof(payload));

  // prepare the payload header with "To" Address length (top nibble) and "From" address length (bottom nibble)
  payload[0] = (strlen(FieldGatewayAddress) << 4) | strlen( DeviceId ) ;
  payloadLength += 1;

  // Copy the "To" address into payload
  memcpy(&payload[payloadLength], FieldGatewayAddress, strlen(FieldGatewayAddress));
  payloadLength += strlen(FieldGatewayAddress) ;

  // Copy the "From" into payload
  memcpy(&payload[payloadLength], DeviceId, strlen(DeviceId));
  payloadLength += strlen(DeviceId) ;

  // Read the temperature and humidity values then display nicely
  temperature = TH02.ReadTemperature();
  humidity = TH02.ReadHumidity();

  Serial.print("T:");
  Serial.print( temperature, 1 ) ;
  Serial.print( "C" ) ;

  Serial.print(" H:");
  Serial.print( humidity, 0 ) ;
  Serial.println( "%" ) ;

  // Copy the temperature into the payload
  payload[ payloadLength] = 't';
  payloadLength += 1 ;
  payload[ payloadLength] = ' ';
  payloadLength += 1 ;
  payloadLength += strlen( dtostrf(temperature, -1, 1, (char*)&payload[payloadLength]));
  payload[ payloadLength] = SensorReadingSeperator;
  payloadLength += sizeof(SensorReadingSeperator) ;

  // Copy the humidity into the payload
  payload[ payloadLength] = 'h';
  payloadLength += 1 ;
  payload[ payloadLength] = ' ';
  payloadLength += 1 ;
  payloadLength += strlen( dtostrf(humidity, -1, 0, (char *)&payload[payloadLength]));  

  // display info about payload then send it (No ACK) with LoRa unlike nRF24L01
  Serial.print( "RFM9X/SX127X Payload length:");
  Serial.print( payloadLength );
  Serial.println( " bytes" );

  LoRa.beginPacket();
  LoRa.write( payload, payloadLength );
  LoRa.endPacket();      

  Serial.println("Loop done");

  delay(LoopSleepDelaySeconds * 1000l);
}

In the debugging output the data looked like this

13:40:28-RX From Maduino1 PacketSnr 9.8 Packet RSSI -65dBm RSSI -110dBm = 11 byte message "t 33.7,h 51"
 Sensor Maduino1t Value 33.7
 Sensor Maduino1h Value 51
 AzureIoTHubClient SendEventAsync start
 AzureIoTHubClient SendEventAsync finish
The thread 0x268 has exited with code 0 (0x0).
The thread 0xb28 has exited with code 0 (0x0).
13:40:38-RX From Maduino1 PacketSnr 9.5 Packet RSSI -66dBm RSSI -112dBm = 11 byte message "t 33.9,h 51"
 Sensor Maduino1t Value 33.9
 Sensor Maduino1h Value 51
 AzureIoTHubClient SendEventAsync start
 AzureIoTHubClient SendEventAsync finish
13:40:49-RX From Maduino1 PacketSnr 9.5 Packet RSSI -66dBm RSSI -110dBm = 11 byte message "t 34.0,h 51"
 Sensor Maduino1t Value 34.0
 Sensor Maduino1h Value 51
 AzureIoTHubClient SendEventAsync start
 AzureIoTHubClient SendEventAsync finish

Bill of materials (Prices Sep 2018)

  • Maduino LoRa Radion (868MHz) USD14.10
  • Seeedstudio Temperature&Humidity Sensor USD11.50
  • 4 pin Female Jumper to Grove 4 pin Conversion Cable USD2.90
  • 1 Watt solar panel with wires USD3.80
  • 3000 mAh LI-Ion battery

There is also a 433MHz version available at the same price

The code is pretty basic, it shows how to pack the payload and set the necessary RFM9X/SX127X LoRa module configuration, has no power conservation, advanced wireless configuration etc.

The onboard sockets for battery and charging make the device easier to package and power in the field.

The Grove 4 pin Female Jumper to Grove 4 pin Conversion Cable was a quick & convenient way to get the I2C Grove temperature and humidity sensor connected up.

Then in my Azure IoT Hub monitoring software

MaduinoLoRaAzureIoT20180914