Adafruit Feather M0 RFM95 LoRa Radio Payload Addressing Client

This is a demo AdaFruit Feather Mo0 Radio with LoRa Radio Module client (based on one of the examples from Arduino-LoRa) that uploads telemetry data to my Windows 10 IoT Core on Raspberry PI field gateway proof of concept(PoC).

The Adafruit learn site had sample code based on the RadioHead library which was useful. This device supports 868MHz & 915Mz, there is are other Arduino 32u4 and 433MHz devices available.

Bill of materials (Prices Sep 2018)

  • Adafruit Feather M0 RFM95 LoRa Radio (433 or 900 MHz) USD34.95
  • Seeedstudio Temperature and Humidity Sensor Pro USD11.50
  • Seeedstudio 4 pin Male Jumper to Grove 4 pin Conversion Cable USD2.90

The code is pretty basic, it reads a value from the Seeedstudio temperature and humidity sensor, then packs the payload and sets the necessary RFM9X/SX127X LoRa module configuration, has no power conservation, advanced wireless configuration etc. I had to add an extra include from the dstrtof function

AdaFruitM0Feather

/*
  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

  
RFM9X.IoTCore Payload Addressing
*/ #include #include #include #include const int csPin = 8; // LoRa radio chip select const int resetPin = 4; // LoRa radio reset const int irqPin = 3; // change for your board; must be a hardware interrupt pin // Field gateway configuration const char FieldGatewayAddress[] = "LoRaIoT1"; const float FieldGatewayFrequency = 915000000.0; const byte FieldGatewaySyncWord = 0x12 ; // Payload configuration const int PayloadSizeMaximum = 64 ; byte payload[PayloadSizeMaximum] = ""; const byte SensorReadingSeperator = ',' ; // Manual serial number configuration const char DeviceId[] = {"AdafruitM0"}; 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 messages 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 Arduino debug monitor the messages from the device looked like this

Loop done
Loop called
T:17.5C H:94%
RFM9X/SX127X Payload length:30 bytes
Loop done
Loop called
T:17.5C H:95%
RFM9X/SX127X Payload length:30 bytes
Loop done
Loop called
T:17.6C H:95%
RFM9X/SX127X Payload length:30 bytes
Loop done

In the debug output window the messages from the device looked like this

The thread 0xf9c has exited with code 0 (0x0).
The thread 0x8ac has exited with code 0 (0x0).
09:53:53-RX From AdafruitM0 PacketSnr 10.3 Packet RSSI -51dBm RSSI -103dBm = 11 byte message "t 17.8,h 93"
Sensor AdafruitM0t Value 17.8
Sensor AdafruitM0h Value 93
AzureIoTHubClient SendEventAsync start
AzureIoTHubClient SendEventAsync finish
The thread 0x704 has exited with code 0 (0x0).
The thread 0xad4 has exited with code 0 (0x0).
09:54:03-RX From AdafruitM0 PacketSnr 9.8 Packet RSSI -52dBm RSSI -101dBm = 11 byte message "t 17.8,h 93"
Sensor AdafruitM0t Value 17.8
Sensor AdafruitM0h Value 93
AzureIoTHubClient SendEventAsync start
AzureIoTHubClient SendEventAsync finish
The thread 0x1084 has exited with code 0 (0x0).
The thread 0xa2c has exited with code 0 (0x0).
09:54:14-RX From AdafruitM0 PacketSnr 9.8 Packet RSSI -54dBm RSSI -102dBm = 11 byte message "t 17.7,h 93"
Sensor AdafruitM0t Value 17.7
Sensor AdafruitM0h Value 93
AzureIoTHubClient SendEventAsync start
AzureIoTHubClient SendEventAsync finish
The thread 0x1720 has exited with code 0 (0x0).

10:00:06-RX From AdafruitM0 PacketSnr 9.3 Packet RSSI -52dBm RSSI -100dBm = 12 byte message "t 184.0,h 91"
Sensor AdafruitM0t Value 184.0
Sensor AdafruitM0h Value 91
AzureIoTHubClient SendEventAsync start
AzureIoTHubClient SendEventAsync finish
The thread 0x15d4 has exited with code 0 (0x0).
The thread 0x15f4 has exited with code 0 (0x0).
10:00:19-RX From AdafruitM0 PacketSnr 10.0 Packet RSSI -48dBm RSSI -102dBm = 12 byte message "t 180.9,h 94"
Sensor AdafruitM0t Value 180.9
Sensor AdafruitM0h Value 94
AzureIoTHubClient SendEventAsync start
AzureIoTHubClient SendEventAsync finish
The thread 0xabc has exited with code 0 (0x0).
The thread 0x2e4 has exited with code 0 (0x0).
10:00:29-RX From AdafruitM0 PacketSnr 9.8 Packet RSSI -49dBm RSSI -102dBm = 12 byte message "t -50.0,h 94"
Sensor AdafruitM0t Value -50.0
Sensor AdafruitM0h Value 94
AzureIoTHubClient SendEventAsync start
AzureIoTHubClient SendEventAsync finish
The thread 0x950 has exited with code 0 (0x0).
The thread 0x145c has exited with code 0 (0x0).
The thread 0x176c has exited with code 0 (0x0).
10:00:39-RX From AdafruitM0 PacketSnr 9.5 Packet RSSI -50dBm RSSI -102dBm = 11 byte message "t 17.5,h 94"
Sensor AdafruitM0t Value 17.5
Sensor AdafruitM0h Value 94
AzureIoTHubClient SendEventAsync start
AzureIoTHubClient SendEventAsync finish
The thread 0x165c has exited with code 0 (0x0).
The thread 0x6e8 has exited with code 0 (0x0).
10:00:49-RX From AdafruitM0 PacketSnr 9.8 Packet RSSI -59dBm RSSI -100dBm = 11 byte message "t 17.5,h 95"
Sensor AdafruitM0t Value 17.5
Sensor AdafruitM0h Value 95
AzureIoTHubClient SendEventAsync start
AzureIoTHubClient SendEventAsync finish
The thread 0x1334 has exited with code 0 (0x0).
The thread 0x14d0 has exited with code 0 (0x0).
10:00:59-RX From AdafruitM0 PacketSnr 9.5 Packet RSSI -66dBm RSSI -102dBm = 11 byte message "t 17.6,h 95"
Sensor AdafruitM0t Value 17.6
Sensor AdafruitM0h Value 95
AzureIoTHubClient SendEventAsync start
AzureIoTHubClient SendEventAsync finish

Then at my Azure IoT hub the data stream looked like this
AdaFruitM0LoRaFeatherIoTHub

To reduce power consumption I would disconnect/remove the light emitting diode(LED)

IoT.Net LoRa Radio 915 MHz Payload Addressing client

This is a demo ingenuity micro IoT.Net 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. 

Thought the silk screen says RFM69 this is a prototype running an RFM95 module.

iotnetlora.jpg

Bill of materials (Prices Sep 2018)

  • IoT.Net device (Beta tester will add price when available)

The device has an onboard MCP9808 temperature sensor which kept the BoM really short. I have had to make some modifications to my RFM9XLoRaNetMF library as the IoT.Net device uses a different SPI port. The code for this devices and the changes will be uploaded to GitHub in the next couple of days.

//---------------------------------------------------------------------------------
// Copyright (c) Sept 2018, 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.
// git remote add origin https://github.com/KiwiBryn/FieldGateway.LoRa.IoTNetClient.git
// git push -u origin master
//---------------------------------------------------------------------------------
namespace devMobile.IoT.IoTNet.FieldGateway
{
	using System;
	using System.Text;
	using System.Threading;
	using Microsoft.SPOT;
	using Microsoft.SPOT.Hardware;
	using devMobile.IoT.NetMF.ISM;
	using IngenuityMicro.Sensors;

	class IoTNetClient
	{
		private readonly Rfm9XDevice rfm9XDevice;
		private readonly TimeSpan dueTime = new TimeSpan(0, 0, 10);
		private readonly TimeSpan periodTime = new TimeSpan(0, 0, 30);
		private readonly MCP9808 mcp9808 = new MCP9808();
		private readonly OutputPort _led = new OutputPort((Cpu.Pin)16 + 8, false);
		private readonly byte[] fieldGatewayAddress = Encoding.UTF8.GetBytes("LoRaIoT1");
		private readonly byte[] deviceAddress = Encoding.UTF8.GetBytes("IoTNet1");

		public IoTNetClient()
		{
			rfm9XDevice = new Rfm9XDevice( SPI.SPI_module.SPI3, (Cpu.Pin)16 + 9, (Cpu.Pin)5, (Cpu.Pin)4);
		}

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

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

			Timer temperatureUpdates = new Timer(TemperatureTimerProc, null, dueTime, periodTime);

			Thread.Sleep(Timeout.Infinite);
		}

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

			double temperature = mcp9808.ReadTempInC();

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

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

			_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);
			}
		}
	}
}
}

.Net Framework debug output Field Gateway

22:55:39-RX From IoTNet1 PacketSnr 9.5 Packet RSSI -50dBm RSSI -110dBm = 6 byte message "t 23.6"
 Sensor IoTNet1t Value 23.6
 AzureIoTHubClient SendEventAsync start
 AzureIoTHubClient SendEventAsync finish
The thread 0xbec has exited with code 0 (0x0).
The thread 0xbb4 has exited with code 0 (0x0).
The thread 0xa0c has exited with code 0 (0x0).
The thread 0x13c has exited with code 0 (0x0).
22:56:09-RX From IoTNet1 PacketSnr 9.3 Packet RSSI -44dBm RSSI -102dBm = 6 byte message "t 23.8"
 Sensor IoTNet1t Value 23.8
 AzureIoTHubClient SendEventAsync start
 AzureIoTHubClient SendEventAsync finish

A small footprint, battery powered .NetMF 4.4 LoRa device designed and made in New Zealand with Visual Studio 2017 support is great.

Elecrow 32u4 with Lora RFM95 IOT Board Payload Addressing Client

This is a demo Elecrow 32u4 with Lora RFM95 IOT Board-868MHz/915MHz client (based on one of the examples from Arduino-LoRa) that uploads telemetry data to my Windows 10 IoT Core on Raspberry PI field gateway proof of concept(PoC).

The elecrow wiki had sample code based on the RadioHead library which was useful.

Bill of materials (Prices Sep 2018)

  • 32u4 with Lora RFM95 IOT Board-868MHz/915MHz USD22.50
  • Seeedstudio LightLevel Sensor USD2.90
  • Elecrow Crowtail to Grove 4 pin Conversion Cable USD1.00

The code is pretty basic, it reads a value from the light sensor, scales it, then packs the payload and sets the necessary RFM9X/SX127X LoRa module configuration, has no power conservation, advanced wireless configuration etc.

Elecrow32u4LoRa

/*
  Adapted from LoRa Duplex communication with Sync Word

  Sends Light data from Seeedstudio 

   https://www.seeedstudio.com/Grove-Light-Sensor-v1-2-p-2727.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
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 byte FieldGatewaySyncWord = 0x12 ;

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

// Manual serial number configuration
const char DeviceId[] = {"Elecrow32u4"};

const int analogInPin = A0;
const int LoopSleepDelaySeconds = 60 ;

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

  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 messages from this device
  LoRa.enableCrc();
  LoRa.setSyncWord(FieldGatewaySyncWord);  

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

  Serial.println("Setup done");
}

void loop()
{
  int payloadLength = 0 ;
  int sensorValue = 0;
  int outputValue = 0; 

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

  // Scale the sensor value to a %
  sensorValue = analogRead(analogInPin);
  outputValue = map(sensorValue, 0, 1023, 0, 100);  

  // 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) ;

  Serial.println("Loop called 5");

  Serial.print("L:");
  Serial.print( outputValue ) ;
  Serial.println( "%" ) ;

  // Copy the temperature into the payload
  payload[ payloadLength] = 'l';
  payloadLength += 1 ;
  payload[ payloadLength] = ' ';
  payloadLength += 1 ;
  payloadLength += strlen( itoa(outputValue, &payload[payloadLength],10 ));  

  // 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 debug output window the messages from the device looked like this

14:06:38-RX From Elecrow32u4 PacketSnr 9.8 Packet RSSI -88dBm RSSI -110dBm = 4 byte message "l 85"
Sensor Elecrow32u4l Value 85
AzureIoTHubClient SendEventAsync start
AzureIoTHubClient SendEventAsync finish
The thread 0x930 has exited with code 0 (0x0).
The thread 0xb74 has exited with code 0 (0x0).
The thread 0x3c8 has exited with code 0 (0x0).
The thread 0x984 has exited with code 0 (0x0).
14:07:01-RX From IoTMCU915 PacketSnr 9.3 Packet RSSI -87dBm RSSI -110dBm = 12 byte message "t 13.7,h 113"
Sensor IoTMCU915t Value 13.7
Sensor IoTMCU915h Value 113
AzureIoTHubClient SendEventAsync start
AzureIoTHubClient SendEventAsync finish
The thread 0x6e8 has exited with code 0 (0x0).
The thread 0x7b4 has exited with code 0 (0x0).
The thread 0xe9c has exited with code 0 (0x0).

My battery is a bit of an overkill and to reduce power consumption I would disconnect/remove the light emitting diode(LED)

LoRa Radio Node v1.0 868/915MHz Payload Addressing Client

This is a demo IoTMCU LoRa Radio Node V1.0 868/915MHz client (based on one of the examples from Arduino-LoRa) that uploads telemetry data to my Windows 10 IoT Core on Raspberry PI field gateway proof of concept(PoC).

The devices arrived promptly and the sample code and schematics made adapting my Arduino code easy.

Bill of materials (Prices Sep 2018)

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.

IoTMCULoRa915V2

/*
  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 byte FieldGatewaySyncWord = 0x12 ;

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

// Manual serial number configuration
const char DeviceId[] = {"IoTMCU915"};

const int LoopSleepDelaySeconds = 60 ;

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 messages 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, &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, &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 debug output window the messages from the device looked like this

Register 0x40 – Value 0X00 – Bits 00000000
Register 0x41 – Value 0X00 – Bits 00000000
Register 0x42 – Value 0X12 – Bits 00010010

The thread 0x6f8 has exited with code 0 (0x0).
The thread 0x2f0 has exited with code 0 (0x0).
19:35:35-RX From IoTMCU915 PacketSnr 10.0 Packet RSSI -45dBm RSSI -109dBm = 11 byte message "t 19.8,h 88"
Sensor IoTMCU915t Value 19.8
Sensor IoTMCU915h Value 88
AzureIoTHubClient SendEventAsync start
AzureIoTHubClient SendEventAsync finish
The thread 0x9b0 has exited with code 0 (0x0).
The thread 0x9f4 has exited with code 0 (0x0).
The thread 0x9dc has exited with code 0 (0x0).
The thread 0x17fc has exited with code 0 (0x0).
The thread 0x944 has exited with code 0 (0x0).
19:36:35-RX From IoTMCU915 PacketSnr 10.8 Packet RSSI -45dBm RSSI -108dBm = 11 byte message "t 19.7,h 88"
Sensor IoTMCU915t Value 19.7
Sensor IoTMCU915h Value 88
AzureIoTHubClient SendEventAsync start
AzureIoTHubClient SendEventAsync finish
The thread 0xbf0 has exited with code 0 (0x0).

I have some suitable batteries on order from Jaycar a local supplier. There is also a 433MHz version of this device available other regions.

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#includeconst int csPin = 10; // LoRa radio chip selectconst int resetPin = 9; // LoRa radio resetconst int irqPin = 2; // change for your board; must be a hardware interrupt pin// Field gateway configurationconst char FieldGatewayAddress[] = "LoRaIoT1";const float FieldGatewayFrequency = 915000000.0;//const float FieldGatewayFrequency = 433000000.0;const byte FieldGatewaySyncWord = 0x12 ;// Payload configurationconst int PayloadSizeMaximum = 64 ;byte payload[PayloadSizeMaximum] = "";const byte SensorReadingSeperator = ',' ;// Manual serial number configurationconst 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 &amp;amp;amp;amp;amp;amp;amp;amp;amp; 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) &lt;&lt; 4) | strlen( DeviceId ) ; payloadLength += 1; // Copy the "To" address into payload memcpy(&amp;amp;amp;amp;amp;amp;amp;amp;amp;payload[payloadLength], FieldGatewayAddress, strlen(FieldGatewayAddress)); payloadLength += strlen(FieldGatewayAddress) ; // Copy the "From" into payload memcpy(&amp;amp;amp;amp;amp;amp;amp;amp;amp;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*)&amp;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 *)&amp;[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
			

Windows 10 IoT Core LoRa library

I have a pair of Windows 10 IoT Core nRF24L01 field gateway projects, one for AdaFruit.IO and the other for Azure IoTHub (Including Azure IoT Central). I use these field gateways for small scale indoor and outdoor deployments.

For larger systems e.g a school campus I was looking for something with a bit more range (line of site + in building penetration) and clients with lower power consumption (suitable for long term battery or solar power).

Other makers had had success with RFM69(proprietary) and RFM9X (LoRA) based devices and shields/hats so I had a look at both technologies.

To kick things off I purchased

I then did some searching and downloaded two commonly used libraries

Initially I trialled the emmellsoft Windows 10 IoT Core Dragino.LoRa code on a couple of Raspberry PI devices.

RPIDraginoP2P

After updating the Windows 10 Min/Max versions, plus the NuGet packages and setting the processor type to ARM the code compiled, downloaded and ran which was a pretty good start.

I could see messages being transmitted and received by the two devices


Packet RSSI: -33, RSSI: -91, SNR: 8, Length: 5

Message Received: CRC OK, Rssi=-91, PacketRssi=-33, PacketSnr=8, Buffer:[55, ff, 00, aa, 01], 2018-07-30 09:27:48

Successfully sent in 110 milliseconds.

Packet RSSI: -15, RSSI: -100, SNR: 9.2, Length: 5

Message Received: CRC OK, Rssi=-100, PacketRssi=-15, PacketSnr=9.2, Buffer:[55, ff, 00, aa, 02], 2018-07-30 09:27:53

Successfully sent in 36 milliseconds.

Packet RSSI: -35, RSSI: -101, SNR: 9, Length: 5

Message Received: CRC OK, Rssi=-101, PacketRssi=-35, PacketSnr=9, Buffer:[55, ff, 00, aa, 03], 2018-07-30 09:27:58

Successfully sent in 36 milliseconds.

I added my first attempt at device configuration for New Zealand (based on EU settings) in Dragino.LoRa\Radio\TransceiverSettings.cs


public static readonly TransceiverSettings ANZ915 = new TransceiverSettings(

RadioModemKind.Lora,

915000000,

BandWidth.BandWidth_125_00_kHz,

SpreadingFactor.SF7,

CodingRate.FourOfFive,

8,

true,

false,

LoraSyncWord.Public);

The LoraSyncWord.Public would turn out to be a problem later!

Then I modified the sender and receiver sample application MainPage.xaml.cs files to reference my settings


private static TransceiverSettings GetRadioSettings()

{

// *********************************************************************************************

// #1/2. YOUR EDITING IS REQUIRED HERE!

//

// Choose transeiver settings:

// *********************************************************************************************

return TransceiverSettings.Standard.ANZ915;

}

I modified one of the RadioHead sample Arduino applications (centre frequency) and deployed it to a LoRa MiniDev device. I could see messages getting sent but they were not getting received by the RPI(s).

So I dumped the registers for the SX127X device in the HopeRF RFM95 module on both devices,

DraginoLoraMinDev

From the device on RPI Hat


SX1276/77/78/79 detected, starting.

1-85

2-1A

3-B

4-0

5-52

6-E4

7-C0

8-0

9-85

A-9

B-2B

C-23

D-0

E-80

F-0

10-0

11-0

12-0

13-0

14-0

15-0

16-0

17-0

18-4

19-0

1A-0

1B-42

1C-0

1D-72

1E-74

1F-9F

20-0

21-8

22-1

23-FF

24-0

25-0

26-4

27-0

28-0

29-0

2A-0

2B-0

2C-9

2D-50

2E-14

2F-45

30-55

31-C3

32-5

33-27

34-1C

35-A

36-3

37-A

38-42

39-34

The LoRa transceiver is initiated successfully.

I printed out the Radiohead and emmellsoft registers then manually compared them using the SX1276 datasheet for reference.

I found the 3 registers which contain the MSB, ISB and LSB for the centre frequency weren’t being calculated correctly (checked this by changing the frequency to 434MHz and comparing the register values to the worked example in the datasheet).

I manually “brute forced” the centre frequency registers in LoRaTransceiver.cs Init() and the RPI could then detect a signal but couldn’t decode the messages.

I went back to the Register dumps and found the SyncWord (odd name as it is a byte) were different. After updating the RPI settings the devices could exchange packets..


const double RH_RF95_FXOSC = 32000000.0;

const double RH_RF95_FSTEP = RH_RF95_FXOSC / 524288.0;

long frf = (long)(Settings.Frequency / RH_RF95_FSTEP);

byte[] bytes = BitConverter.GetBytes(frf);

byte[] x6 = { bytes[2] };

RegisterManager.WriteRegister(6, x6);

byte[] x7 = { bytes[1] };

RegisterManager.WriteRegister(7, x7);

byte[] x8 = { bytes[0] };

RegisterManager.WriteRegister(8, x8);

RegisterManager.Write(new LoraRegisterSyncWord(Settings.LoraSyncWord.Value));

This was not a long term solution, lots of code, and register setting changes with limited explanation…