DF Robot Temperature & Humidity Sensor(SHT20) trial

In preparation for a project to build weather stations to place at a couple of local schools I purchased a DF Robot SHT20 Temperature & Humidity Sensor for evaluation.

Seeeduino Nano, EasySensors Shield & DF Robot Sensor test rig

The Seeeduino Nano devices I’m testing have a single on-board I2C socket which meant I didn’t need a Grove Shield for Arduino Nano which reduced the size and cost of the sensor node.

To test my setup I installed the DFRobot Arduino SHT20 library and downloaded a demo application to my device.

I started with my Easy Sensors Arduino Nano Radio Shield RFM69/95 Payload Addressing client and modified it to use the SHT20 sensor.

/*
  Copyright ® 2019 August devMobile Software, All Rights Reserved

  THIS CODE AND INFORMATION IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY
  KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
  IMPLIED WARRANTIES OF MERCHANTABILITY AND/OR FITNESS FOR A PARTICULAR
  PURPOSE.

  You can do what you want with this code, acknowledgment would be nice.
  http://www.devmobile.co.nz

  DF Robot SHT20 Temperature & Humidity sensor   https://www.dfrobot.com/wiki/index.php/SHT20_I2C_Temperature_%26_Humidity_Sensor_(Waterproof_Probe)_SKU:_SEN0227  

  Seeeduino Nano 
  https://www.seeedstudio.com/Seeeduino-Nano-p-4111.html
  
  Polycarbonate enclosure approx 3.5" x 4.5"
    2 x Cable glands
    1 x ufl to SMA connector
    3M command adhesive strips to hold battery & device in place
   
*/
#include <stdlib.h&gt;
#include <DFRobot_SHT20.h&gt;
#include <LoRa.h&gt;
#include <sha204_library.h&gt;

//#define DEBUG
//#define DEBUG_TELEMETRY
//#define DEBUG_LORA
//#define DEBUG_TEMPERATURE_AND_HUMIDITY

#define UNITS_HUMIDITY "%"
#define UNITS_TEMPERATURE "°c"

// LoRa field gateway configuration (these settings must match your field gateway)
const byte DeviceAddressMaximumLength = 15 ;
const char FieldGatewayAddress[] = {"LoRaIoT1"};
const float FieldGatewayFrequency =  915000000.0;
const byte FieldGatewaySyncWord = 0x12 ;

// Payload configuration
const int ChipSelectPin = 10;
const int ResetPin = 9;
const int InterruptPin = 2;

// LoRa radio payload configuration
const byte SensorIdValueSeperator = ' ' ;
const byte SensorReadingSeperator = ',' ;
const unsigned long SensorUploadDelay = 60000;

// ATSHA204 secure authentication, validation with crypto and hashing (currently only using for unique serial number)
const byte Atsha204Port = A3;
atsha204Class sha204(Atsha204Port);
const byte DeviceSerialNumberLength = 9 ;
byte deviceSerialNumber[DeviceSerialNumberLength] = {""};

// SHT20 Air temperature and humidity sensor
DFRobot_SHT20 sht20;

const byte PayloadSizeMaximum = 64 ;
byte payload[PayloadSizeMaximum];
byte payloadLength = 0 ;


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

#ifdef DEBUG
  while (!Serial);
#endif
 
  Serial.println("Setup called");

  Serial.print("Field gateway:");
  Serial.print(FieldGatewayAddress ) ;
  Serial.print(" Frequency:");
  Serial.print( FieldGatewayFrequency,0 ) ;
  Serial.print("MHz SyncWord:");
  Serial.print( FieldGatewaySyncWord ) ;
  Serial.println();
  
   // Retrieve the serial number then display it nicely
  if(sha204.getSerialNumber(deviceSerialNumber))
  {
    Serial.println("sha204.getSerialNumber failed");
    while (true); // Drop into endless loop requiring restart
  }

  Serial.print("SNo:");
  DisplayHex( deviceSerialNumber, DeviceSerialNumberLength);
  Serial.println();

  Serial.println("LoRa setup start");

  // override the default chip select and reset pins
  LoRa.setPins(ChipSelectPin, ResetPin, InterruptPin);
  if (!LoRa.begin(FieldGatewayFrequency))
  {
    Serial.println("LoRa begin failed");
    while (true); // Drop into endless loop requiring restart
  }

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

#ifdef DEBUG_LORA
  LoRa.dumpRegisters(Serial);
#endif
  Serial.println("LoRa Setup done.");

  // Configure the DF Robot SHT20, temperature &amp; humidity sensor
  Serial.println("SHT20 setup start");  
  sht20.initSHT20();
  delay(100);
  sht20.checkSHT20();    
  Serial.println("SHT20 setup done");

  PayloadHeader((byte *)FieldGatewayAddress,strlen(FieldGatewayAddress), deviceSerialNumber, DeviceSerialNumberLength);

  Serial.println("Setup done");
  Serial.println();
}


void loop()
{
  unsigned long currentMilliseconds = millis();  
  float temperature ;
  float humidity ;

  Serial.println("Loop called");

  PayloadReset();  

  humidity = sht20.readHumidity();          
  PayloadAdd( "h", humidity, 0, false);

  temperature = sht20.readTemperature();               
  PayloadAdd( "t", temperature, 1, false);
  
  #ifdef DEBUG_TEMPERATURE_AND_HUMIDITY  
    Serial.print("H:");
    Serial.print( humidity, 0 ) ;
    Serial.print( UNITS_HUMIDITY ) ;
    Serial.print("T:");
    Serial.print( temperature, 1 ) ;
    Serial.println( UNITS_TEMPERATURE ) ;
  #endif

  #ifdef DEBUG_TELEMETRY
    Serial.println();
    Serial.print("RFM9X/SX127X Payload length:");
    Serial.print(payloadLength);
    Serial.println(" bytes");
  #endif

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

  Serial.println("Loop done");
  Serial.println();

  delay(SensorUploadDelay - (millis() - currentMilliseconds ));
}


void PayloadHeader( const byte *to, byte toAddressLength, const byte *from, byte fromAddressLength)
{
  byte addressesLength = toAddressLength + fromAddressLength ;

  payloadLength = 0 ;

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

  // Copy the "To" address into payload
  memcpy(&amp;payload[payloadLength], to, toAddressLength);
  payloadLength += toAddressLength ;

  // Copy the "From" into payload
  memcpy(&amp;payload[payloadLength], from, fromAddressLength);
  payloadLength += fromAddressLength ;
}


void PayloadAdd( const char *sensorId, float value, byte decimalPlaces, bool last)
{
  byte sensorIdLength = strlen( sensorId ) ;

  memcpy( &amp;payload[payloadLength], sensorId,  sensorIdLength) ;
  payloadLength += sensorIdLength ;
  payload[ payloadLength] = SensorIdValueSeperator;
  payloadLength += 1 ;
  payloadLength += strlen( dtostrf(value, -1, decimalPlaces, (char *)&amp;payload[payloadLength]));
  if (!last)
  {
    payload[ payloadLength] = SensorReadingSeperator;
    payloadLength += 1 ;
  }
  
#ifdef DEBUG_TELEMETRY
  Serial.print("PayloadAdd float-payloadLength:");
  Serial.print( payloadLength);
  Serial.println( );
#endif
}


void PayloadAdd( char *sensorId, int value, bool last )
{
  byte sensorIdLength = strlen(sensorId) ;

  memcpy(&amp;payload[payloadLength], sensorId,  sensorIdLength) ;
  payloadLength += sensorIdLength ;
  payload[ payloadLength] = SensorIdValueSeperator;
  payloadLength += 1 ;
  payloadLength += strlen(itoa( value,(char *)&amp;payload[payloadLength],10));
  if (!last)
  {
    payload[ payloadLength] = SensorReadingSeperator;
    payloadLength += 1 ;
  }
  
#ifdef DEBUG_TELEMETRY
  Serial.print("PayloadAdd int-payloadLength:" );
  Serial.print(payloadLength);
  Serial.println( );
#endif
}


void PayloadAdd( char *sensorId, unsigned int value, bool last )
{
  byte sensorIdLength = strlen(sensorId) ;

  memcpy(&amp;payload[payloadLength], sensorId,  sensorIdLength) ;
  payloadLength += sensorIdLength ;
  payload[ payloadLength] = SensorIdValueSeperator;
  payloadLength += 1 ;
  payloadLength += strlen(utoa( value,(char *)&amp;payload[payloadLength],10));
  if (!last)
  {
    payload[ payloadLength] = SensorReadingSeperator;
    payloadLength += 1 ;
  }
  
#ifdef DEBUG_TELEMETRY
  Serial.print("PayloadAdd uint-payloadLength:");
  Serial.print(payloadLength);
  Serial.println( );
#endif
}


void PayloadReset()
{
  byte fromAddressLength = payload[0] &amp; 0xf ;
  byte toAddressLength = payload[0] &gt;&gt; 4 ;
  
  payloadLength = toAddressLength + fromAddressLength + 1;
}


void DisplayHex( byte *byteArray, byte length) 
{
  for (int i = 0; i < length ; i++)
  {
    // Add a leading zero
    if ( byteArray[i] < 16)
    {
      Serial.print("0");
    }
    Serial.print(byteArray[i], HEX);
    if ( i < (length-1)) // Don't put a - after last digit
    {
      Serial.print("-");
    }
  }
}    

The code is available on GitHub.

20:52:09.656 -> Setup called
20:52:09.690 -> Field gateway:LoRaIoT1 Frequency:915000000MHz SyncWord:18
20:52:09.794 -> SNo:01-23-21-61-D6-D1-F5-86-EE
20:52:09.828 -> LoRa setup start
20:52:09.828 -> LoRa Setup done.
20:52:09.862 -> SHT20 setup start
20:52:09.932 -> End of battery: no
20:52:09.932 -> Heater enabled: no
20:52:09.965 -> Disable OTP reload: yes
20:52:09.999 -> SHT20 setup done
20:52:09.999 -> Setup done
20:52:09.999 -> 
20:52:09.999 -> Loop called
20:52:10.067 -> H:60%T:20.0°c
20:52:10.136 -> Loop done
20:52:10.136 -> 
20:53:09.915 -> Loop called
20:53:10.019 -> H:61%T:20.5°c
20:53:10.088 -> Loop done
20:53:10.088 -> 

To configure the device in Azure IoT Central (similar process for Adafruit.IO, working on support for losant, ubidots and MyDevices) I copied the SNo: from the Arduino development tool logging window and appended p10 for PM 1 value, p25 for PM2.5 value and p100 for PM10 value to the unique serial number from the ATSHA204A chip. (N.B. pay attention to the case of the field names they are case sensitive)

When I moved the sensor indoors it appeared to take a while to warm up and after a while the metal body still felt cold. The sensor element is surrounded by quite a bit of protective packaging for outdoors use and I that would have a bit more thermal inertia the than the lightweight indoor enclosure.

It would be good to run the sensor alongside a calibrated temperature & humidity sensor to see how accurate and responsive it is.

Bill of materials (prices as at August 2019)

  • Seeeduino Nano USD6.90
  • Grove Screw Terminal USD2.90
  • DF Robot SHT20 I2C Temperature & Humidity Sensor USD22.50
  • EasySensors Arduino Nano radio shield RFM95 USD15.00

STM32 Blue Pill LoRaWAN node

A few weeks ago I ordered an STM32 Blue Pill LoRaWAN node from the M2M Shop on Tindie for evaluation. I have bought a few M2M client devices including a Low power LoRaWan Node Model A328, and Low power LoRaWan Node Model B1284 for projects and they have worked well. This one looked interesting as I had never used a maple like device before.

Bill of materials (Prices as at July 2019)

  • STM32 Blue Pill LoRaWAN node USD21
  • Grove – Temperature&Humidity Sensor USD11.5
  • Grove – 4 pin Female Jumper to Grove 4 pin Conversion Cable USD3.90

The two sockets on the main board aren’t Grove compatible so I used the 4 pin female to Grove 4 pin conversion cable to connect the temperature and humidity sensor.

STM32 Blue Pill LoRaWAN node test rig

I used a modified version of my Arduino client code which worked after I got the pin reset pin sorted and the female sockets in the right order.

/*
  Copyright ® 2019 July devMobile Software, All Rights Reserved

  THIS CODE AND INFORMATION IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY
  KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
  IMPLIED WARRANTIES OF MERCHANTABILITY AND/OR FITNESS FOR A PARTICULAR
  PURPOSE.
  
  Adapted from LoRa Duplex communication with Sync Word

  Sends temperature &amp; 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 <itoa.h&gt;     
#include <SPI.h&gt;     
#include <LoRa.h&gt;

#include <TH02_dev.h&gt;

#define DEBUG
//#define DEBUG_TELEMETRY
//#define DEBUG_LORA

// LoRa field gateway configuration (these settings must match your field gateway)
const char DeviceAddress[] = {"BLUEPILL"};

// Azure IoT Hub FieldGateway
const char FieldGatewayAddress[] = {"LoRaIoT1"}; 
const float FieldGatewayFrequency =  915000000.0;
const byte FieldGatewaySyncWord = 0x12 ;

// Bluepill hardware configuration
const int ChipSelectPin = PA4;
const int InterruptPin = PA0;
const int ResetPin = -1;

// LoRa radio payload configuration
const byte SensorIdValueSeperator = ' ' ;
const byte SensorReadingSeperator = ',' ;
const byte PayloadSizeMaximum = 64 ;
byte payload[PayloadSizeMaximum];
byte payloadLength = 0 ;

const int LoopDelaySeconds = 300 ;

// Sensor configuration
const char SensorIdTemperature[] = {"t"};
const char SensorIdHumidity[] = {"h"};


void setup()
{
  Serial.begin(9600);
#ifdef DEBUG
  while (!Serial);
#endif
  Serial.println("Setup called");

  Serial.println("LoRa setup start");

  // override the default chip select and reset pins
  LoRa.setPins(ChipSelectPin, ResetPin, InterruptPin);
  if (!LoRa.begin(FieldGatewayFrequency))
  {
    Serial.println("LoRa begin failed");
    while (true); // Drop into endless loop requiring restart
  }

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

#ifdef DEBUG_LORA
  LoRa.dumpRegisters(Serial);
#endif
  Serial.println("LoRa setup done.");

  PayloadHeader((byte*)FieldGatewayAddress, strlen(FieldGatewayAddress), (byte*)DeviceAddress, strlen(DeviceAddress));

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

  Serial.println("Setup done");
}

void loop() {
  // read the value from the sensor:
  double temperature = TH02.ReadTemperature();
  double humidity = TH02.ReadHumidity();

  Serial.print("Humidity: ");
  Serial.print(humidity, 0);
  Serial.print(" %\t");
  Serial.print("Temperature: ");
  Serial.print(temperature, 1);
  Serial.println(" *C");

  PayloadReset();

  PayloadAdd(SensorIdHumidity, humidity, 0) ;
  PayloadAdd(SensorIdTemperature, temperature, 1) ;

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

  Serial.println("Loop done");

  delay(LoopDelaySeconds * 1000);
}


void PayloadHeader( byte *to, byte toAddressLength, byte *from, byte fromAddressLength)
{
  byte addressesLength = toAddressLength + fromAddressLength ;

#ifdef DEBUG_TELEMETRY
  Serial.println("PayloadHeader- ");
  Serial.print( "To Address len:");
  Serial.print( toAddressLength );
  Serial.print( " From Address len:");
  Serial.print( fromAddressLength );
  Serial.print( " Addresses length:");
  Serial.print( addressesLength );
  Serial.println( );
#endif

  payloadLength = 0 ;

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

  // Copy the "To" address into payload
  memcpy(&amp;payload[payloadLength], to, toAddressLength);
  payloadLength += toAddressLength ;

  // Copy the "From" into payload
  memcpy(&amp;payload[payloadLength], from, fromAddressLength);
  payloadLength += fromAddressLength ;
}


void PayloadAdd( const char *sensorId, float value, byte decimalPlaces)
{
  byte sensorIdLength = strlen( sensorId ) ;

#ifdef DEBUG_TELEMETRY
  Serial.println("PayloadAdd-float ");
  Serial.print( "SensorId:");
  Serial.print( sensorId );
  Serial.print( " sensorIdLen:");
  Serial.print( sensorIdLength );
  Serial.print( " Value:");
  Serial.print( value, decimalPlaces );
  Serial.print( " payloadLength:");
  Serial.print( payloadLength);
#endif

  memcpy( &amp;payload[payloadLength], sensorId,  sensorIdLength) ;
  payloadLength += sensorIdLength ;
  payload[ payloadLength] = SensorIdValueSeperator;
  payloadLength += 1 ;
  payloadLength += strlen( dtostrf(value, -1, decimalPlaces, (char *)&amp;payload[payloadLength]));
  payload[ payloadLength] = SensorReadingSeperator;
  payloadLength += 1 ;

#ifdef DEBUG_TELEMETRY
  Serial.print( " payloadLength:");
  Serial.print( payloadLength);
  Serial.println( );
#endif
}


void PayloadAdd( const char *sensorId, int value )
{
  byte sensorIdLength = strlen( sensorId ) ;

#ifdef DEBUG_TELEMETRY
  Serial.println("PayloadAdd-int ");
  Serial.print( "SensorId:");
  Serial.print( sensorId );
  Serial.print( " sensorIdLen:");
  Serial.print( sensorIdLength );
  Serial.print( " Value:");
  Serial.print( value );
  Serial.print( " payloadLength:");
  Serial.print( payloadLength);
#endif

  memcpy( &amp;payload[payloadLength], sensorId,  sensorIdLength) ;
  payloadLength += sensorIdLength ;
  payload[ payloadLength] = SensorIdValueSeperator;
  payloadLength += 1 ;
  payloadLength += strlen( itoa( value, (char *)&amp;payload[payloadLength], 10));
  payload[ payloadLength] = SensorReadingSeperator;
  payloadLength += 1 ;

#ifdef DEBUG_TELEMETRY
  Serial.print( " payloadLength:");
  Serial.print( payloadLength);
  Serial.println( );
#endif
}

void PayloadAdd( const char *sensorId, unsigned int value )
{
  byte sensorIdLength = strlen( sensorId ) ;

#ifdef DEBUG_TELEMETRY
  Serial.println("PayloadAdd-unsigned int ");
  Serial.print( "SensorId:");
  Serial.print( sensorId );
  Serial.print( " sensorIdLen:");
  Serial.print( sensorIdLength );
  Serial.print( " Value:");
  Serial.print( value );
  Serial.print( " payloadLength:");
  Serial.print( payloadLength);
#endif

  memcpy( &amp;payload[payloadLength], sensorId,  sensorIdLength) ;
  payloadLength += sensorIdLength ;
  payload[ payloadLength] = SensorIdValueSeperator;
  payloadLength += 1 ;
  payloadLength += strlen( utoa( value, (char *)&amp;payload[payloadLength], 10));
  payload[ payloadLength] = SensorReadingSeperator;
  payloadLength += 1 ;

#ifdef DEBUG_TELEMETRY
  Serial.print( " payloadLength:");
  Serial.print( payloadLength);
  Serial.println( );
#endif
}


void PayloadReset()
{
  byte fromAddressLength = payload[0] &amp; 0xf ;
  byte toAddressLength = payload[0] &gt;&gt; 4 ;
  byte addressesLength = toAddressLength + fromAddressLength ;

  payloadLength = addressesLength + 1;

#ifdef DEBUG_TELEMETRY
  Serial.println("PayloadReset- ");
  Serial.print( "To Address len:");
  Serial.print( toAddressLength );
  Serial.print( " From Address len:");
  Serial.print( fromAddressLength );
  Serial.print( " Addresses length:");
  Serial.print( addressesLength );
  Serial.println( );
#endif
}

To get the application to compile I also had to include itoa.h rather than stdlib.h.

maple_loader v0.1
Resetting to bootloader via DTR pulse
[Reset via USB Serial Failed! Did you select the right serial port?]
Searching for DFU device [1EAF:0003]...
Assuming the board is in perpetual bootloader mode and continuing to attempt dfu programming...

dfu-util - (C) 2007-2008 by OpenMoko Inc.

Initially I had some problems deploying my software because I hadn’t followed the instructions and run the installation batch file.

14:03:56.946 -> Setup called
14:03:56.946 -> LoRa setup start
14:03:56.946 -> LoRa setup done.
14:03:56.946 -> TH02 setup
14:03:57.046 -> TH02 Setup done
14:03:57.046 -> Setup done
14:03:57.115 -> Humidity: 76 %	Temperature: 18.9 *C
14:03:57.182 -> Loop done
14:08:57.226 -> Humidity: 74 %	Temperature: 18.7 *C
14:08:57.295 -> Loop done
14:13:57.360 -> Humidity: 76 %	Temperature: 18.3 *C
14:13:57.430 -> Loop done
14:18:57.475 -> Humidity: 74 %	Temperature: 18.2 *C
14:18:57.544 -> Loop done
14:23:57.593 -> Humidity: 70 %	Temperature: 17.8 *C
14:23:57.662 -> Loop done
14:28:57.733 -> Humidity: 71 %	Temperature: 17.8 *C
14:28:57.802 -> Loop done
14:33:57.883 -> Humidity: 73 %	Temperature: 17.9 *C
14:33:57.952 -> Loop done
14:38:57.997 -> Humidity: 73 %	Temperature: 18.0 *C
14:38:58.066 -> Loop done
14:43:58.138 -> Humidity: 73 %	Temperature: 18.1 *C
14:43:58.208 -> Loop done
14:48:58.262 -> Humidity: 73 %	Temperature: 18.3 *C
14:48:58.331 -> Loop done
14:53:58.374 -> Humidity: 73 %	Temperature: 18.2 *C
14:53:58.444 -> Loop done
14:58:58.509 -> Humidity: 73 %	Temperature: 18.3 *C
14:58:58.578 -> Loop done
15:03:58.624 -> Humidity: 65 %	Temperature: 16.5 *C
15:03:58.694 -> Loop done
15:08:58.766 -> Humidity: 71 %	Temperature: 18.8 *C
15:08:58.836 -> Loop done
15:13:58.893 -> Humidity: 75 %	Temperature: 19.1 *C
15:13:58.963 -> Loop done

I configured the device to upload to my Azure IoT Hub/Azure IoT Central gateway and after getting the device name configuration right it has been running reliably for a couple of days

Azure IoT Central Temperature and humidity

The device was sitting outside on the deck and rapid increase in temperature is me bringing it inside.

Nexus LoRa Radio 915 MHz Payload Addressing client

This is a demo Ingenuity Micro Nexus client (based on the Netduino example for my RFM9XLoRaNetMF library) that uploads temperature and humidity data to my Azure IoT Hubs/Central or AdaFruit.IO on Raspberry PI field gateways

Bill of materials (Prices June 2019).

// <copyright file="client.cs" company="devMobile Software"&gt;
// Copyright ® 2019 Feb devMobile Software, All Rights Reserved
//
//  MIT License
//
//  Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
// SOFTWARE"
//
// </copyright&gt;
namespace devMobile.IoT.Nexus.FieldGateway
{
	using System;
	using System.Text;
	using System.Threading;
	using Microsoft.SPOT;
	using Microsoft.SPOT.Hardware;

	using devMobile.IoT.NetMF.ISM;
	using devMobile.NetMF.Sensor;
	using IngenuityMicro.Nexus;

	class NexusClient
	{
		private Rfm9XDevice rfm9XDevice;
		private readonly TimeSpan dueTime = new TimeSpan(0, 0, 15);
		private readonly TimeSpan periodTime = new TimeSpan(0, 0, 60);
		private readonly SiliconLabsSI7005 sensor = new SiliconLabsSI7005();
		private readonly Led _led = new Led();
		private readonly byte[] fieldGatewayAddress = Encoding.UTF8.GetBytes("LoRaIoT1");
		private readonly byte[] deviceAddress = Encoding.UTF8.GetBytes("Nexus915");

		public NexusClient()
		{
			rfm9XDevice = new Rfm9XDevice(SPI.SPI_module.SPI3, (Cpu.Pin)28, (Cpu.Pin)15, (Cpu.Pin)26);
			_led.Set(0, 0, 0);
		}

		public void Run()
		{

			rfm9XDevice.Initialise(frequency: 915000000, 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.Set(0, 128, 0);

			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")));
		}

		void rfm9XDevice_OnTransmit()
		{
			_led.Set(0, 0, 0);

			Debug.Print("Transmit-Done");
		}

		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);
			}
		}
	}
}

Overall the development process was good with no modifications to my RFM9X.NetMF library or SI7005 library (bar removing a Netduino I2C work around) required

Nexus device with Seeedstudio Temperature & Humidity Sensors
Nexus Sensor data in Azure IoT Hub Field Gateway ETW Logging
Nexus temperature & humidity data displayed in Azure IoT Central

Wisen Whisper Node – LoRa 915 MHz Payload Addressing Client

This is a demo Wizen Whisper NodeLoRa 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 Wisen Bitbucket repository had sample code based on the RadioHead library which was useful for port numbers. This device family supports 433MHz, 868MHz & 915Mz modules. Wisen has other RFM69 based devices as well.

Bill of materials (Prices Sep 2018)

  • Wizen Whisper Node LoRa (433, 868 or 900 MHz) AUD27.90
  • 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. It has no power conservation, advanced wireless configuration etc.

I needed to use jumpers to connect my device up

WisenPatch20180924

WisenLoRa20180924

/*
  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 = 7;       // 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[] = {"Wisen01"};

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 debug output window the messages from the device looked like this

20:38:30-RX From Wisen01 PacketSnr 10.0 Packet RSSI -48dBm RSSI -104dBm = 11 byte message "t 22.2,h 91"
Sensor Wisen01t Value 22.2
Sensor Wisen01h Value 91
AzureIoTHubClient SendEventAsync start
AzureIoTHubClient SendEventAsync finish
The thread 0x14c0 has exited with code 0 (0x0).
The thread 0x788 has exited with code 0 (0x0).
20:38:40-RX From Wisen01 PacketSnr 9.8 Packet RSSI -48dBm RSSI -103dBm = 11 byte message "t 22.5,h 91"
Sensor Wisen01t Value 22.5
Sensor Wisen01h Value 91
AzureIoTHubClient SendEventAsync start
AzureIoTHubClient SendEventAsync finish
The thread 0x1124 has exited with code 0 (0x0).
The thread 0x129c has exited with code 0 (0x0).
20:38:50-RX From Wisen01 PacketSnr 9.3 Packet RSSI -47dBm RSSI -96dBm = 11 byte message "t 22.7,h 91"
Sensor Wisen01t Value 22.7
Sensor Wisen01h Value 91
AzureIoTHubClient SendEventAsync start
AzureIoTHubClient SendEventAsync finish
The thread 0x664 has exited with code 0 (0x0).

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

WisenTalkLoRaAzureIoTHub

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

  https://blog.devmobile.co.nz/2018/09/03/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)

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