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)

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.

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
			

Dragino LoRaMiniDev Payload Addressing Client

This is a demo Dragino LoRa Mini Dev featuring LoRa® technology client (based on one of the examples from Arduino-LoRa) that uploads telemetry data to my AdaFruit.IO and Azure IoT Hubs Windows 10 IoT Core on Raspberry PI proof of concept (PoC) field gateways.

LoRaMiniDevTH02

Bill of materials (Prices Sep 2018)

  • Draguino LoRa MiniDev USD23
  • Seeedstudio Temperature&Humidity Sensor USD11.50 NZD20
  • 4 pin Male Jumper to Grove 4 pin Conversion Cable USD2.90

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

/*
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
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 byte FieldGatewayAddress[] = "LoRaIoT1";
const float FieldGatewayFrequency =  915000000.0;
//const float FieldGatewayFrequency =  433000000.0;
const byte FieldGatewaySyncWord = 0x12 ;

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

// Manual serial number configuration
char DeviceId[] = {"LoRaMiniDev5"};

const int LoopSleepDelaySeconds = 10 ;

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

Serial.print("LoRa Setup-");
Serial.println( DeviceId ) ;

// 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, &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

09:53:05-RX From LoRaMiniDev5 PacketSnr 9.3 Packet RSSI -65dBm RSSI -109dBm = 11 byte message "t 16.8,h 98"
Sensor LoRaMiniDev5t Value 16.8
Sensor LoRaMiniDev5h Value 98
AzureIoTHubClient SendEventAsync start
AzureIoTHubClient SendEventAsync finish
The thread 0xba0 has exited with code 0 (0x0).
The thread 0xb24 has exited with code 0 (0x0).
09:53:15-RX From LoRaMiniDev5 PacketSnr 9.3 Packet RSSI -65dBm RSSI -108dBm = 11 byte message "t 16.7,h 98"
Sensor LoRaMiniDev5t Value 16.7
Sensor LoRaMiniDev5h Value 98
AzureIoTHubClient SendEventAsync start
AzureIoTHubClient SendEventAsync finish
The thread 0x76c has exited with code 0 (0x0).
The thread 0x91c has exited with code 0 (0x0).

Then in my Azure IoT Hub monitoring software
DraginoLoraMinDevEventHub
The dragino LoRa Mini Dev with an external antenna connector would be a good indoor data acquisition node for student project when powered by a 2nd hand cellphone charger.

Azure IoT Hubs LoRa Windows 10 IoT Core Field Gateway

This project is now live on github.com, sample Arduino with Dragino LoRa Shield for Arduino, MakerFabs Maduino, Dragino LoRa Mini Dev, M2M Low power Node and Netduino with Elecrow LoRa RFM95 Shield clients uploaded in the next couple of days.

AzureIOTHubExplorerScreenGrab20180912

The bare minimum configuration is

{
  "AzureIoTHubDeviceConnectionString": "HostName=qwertyuiop.azure-devices.net;DeviceId=LoRaGateway;SharedAccessKey=1234567890qwertyuiop987654321qwertyuiop1234g=",
  "AzureIoTHubTransportType": "Amqp",
  "SensorIDIsDeviceIDSensorID": true,
  "Address": "LoRaIoT1",
  "Frequency": 915000000.0
}

So far battery life and wireless communications range for the Arduino clients is looking pretty good. CRC presence checking and validation is turned so have a look at one of the sample clients.

ArduinoUnoR3DraginoLoRa
It took a bit longer than expected as upgrading to the latest version (v1.18.0 as at 12 Sep 2018) of Microsoft.Azure.Devices.Client (from 1.6.3) broke my field gateway with timeouts and exceptions.

I’ll be doing some more testing over the next couple of weeks so it is a work in progress.

AdaFruit.IO LoRa Windows 10 IoT Core Field Gateway

This project is now live on github.com, sample Arduino with Dragino LoRa Shield for Arduino, MakerFabs Maduino, Dragino LoRa Mini Dev, M2M Low power Node and Netduino with Elecrow LoRa RFM95 Shield clients uploaded in the next couple of days.

AdaFruit.IO.LoRaScreenShot
While building this AdaFruit.IO LoRa field gateway, and sample clients I revisited my RFM9XLoRa-Net library a couple of times adding functionality and renaming constants to make it more consistent. I made many of the default values public so they could be used in the field gateway config file.
The bare minimum configuration is

{
“AdaFruitIOUserName”: “——“,
“AdaFruitIOApiKey”: “——“,
“AdaFruitIOGroupName”: “——”
“Address”: “——“,
“Frequency”: 915000000.0
}

So far battery life and wireless communications range for the Arduino clients is looking pretty good.

ArduinoUnoR3DraginoLoRa

Arduino LoRa Payload Addressing Client

This is a demo Arduino 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).

Bill of materials (Prices Sep 2018)

ArduinoUnoR3DraginoLoRa

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.

/*
  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
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 byte FieldGatewayAddress[] = "LoRaIoT1";
const float FieldGatewayFrequency =  915000000.0;
const byte FieldGatewaySyncWord = 0x12 ;

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

// Manual serial number configuration
char DeviceId[] = {"Arduino1"};

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 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, &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

19:15:21-RX From Arduino1 PacketSnr 9.3 Packet RSSI -49dBm RSSI -105dBm = 11 byte message "t 18.8,h 91"

19:15:30-TX 25 byte message Hello from LoRaIoT1 ! 255
19:15:30-TX Done
19:15:31-RX From Arduino1 PacketSnr 9.3 Packet RSSI -49dBm RSSI -103dBm = 11 byte message "t 18.8,h 91"

19:15:41-RX From Arduino1 PacketSnr 9.3 Packet RSSI -48dBm RSSI -106dBm = 11 byte message "t 18.8,h 91"

There must be a nicer way of building the payload, a topic for a future post maybe.

RFM9X.IoTCore Payload Addressing

The reason for RFM9XLoRaNet was so that I could build a field gateway to upload telemetry data from “cheap n cheerful” *duino devices to Azure IoT Hubs and AdaFruit.IO.

I have extended the Windows10IoTCore sample application and library to show how the conditional compilation directive ADDRESSED_MESSAGES_PAYLOAD controls the configuration.

When the application is started the RFM9X is in sleep mode, then when the Receive method is called the device is set to ReceiveContinuous.

public void Run(IBackgroundTaskInstance taskInstance)
{
   rfm9XDevice.Initialise(915000000.0, paBoost: true, rxPayloadCrcOn : true);

#if DEBUG
   rfm9XDevice.RegisterDump();
#endif

#if ADDRESSED_MESSAGES_PAYLOAD
   rfm9XDevice.OnReceive += Rfm9XDevice_OnReceive;
   rfm9XDevice.Receive(UTF8Encoding.UTF8.GetBytes(Environment.MachineName));
#else
   rfm9XDevice.Receive();
#endif
   rfm9XDevice.OnTransmit += Rfm9XDevice_OnTransmit;

   Task.Delay(10000).Wait();

   while (true)
   {
      string messageText = string.Format("Hello from {0} ! {1}", Environment.MachineName, NessageCount);
      MessageCount -= 1;

      byte[] messageBytes = UTF8Encoding.UTF8.GetBytes(messageText);
      Debug.WriteLine("{0:HH:mm:ss}-TX {1} byte message {2}", DateTime.Now, messageBytes.Length, messageText);
#if ADDRESSED_MESSAGES_PAYLOAD
      this.rfm9XDevice.Send(UTF8Encoding.UTF8.GetBytes("AddressGoesHere"), messageBytes);
#else
      this.rfm9XDevice.Send(messageBytes);
#endif
      Task.Delay(10000).Wait();
   }
}

On receipt of a message, the message is parsed and the to/from addresses and payload extracted (ADDRESSED_MESSAGES defined) or passed to the client application for processing.

private void Rfm9XDevice_OnReceive(object sender, Rfm9XDevice.OnDataReceivedEventArgs e)
{
   try
   {
      string messageText = UTF8Encoding.UTF8.GetString(e.Data);

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

      Debug.WriteLine(@"{0:HH:mm:ss}-RX From {1} PacketSnr {2:0.0} Packet RSSI {3}dBm RSSI {4}dBm = {5} byte message ""{6}""", DateTime.Now, addressText, e.PacketSnr, e.PacketRssi, e.Rssi, e.Data.Length, messageText);
#else
      Debug.WriteLine(@"{0:HH:mm:ss}-RX PacketSnr {1:0.0} Packet RSSI {2}dBm RSSI {3}dBm = {4} byte message ""{5}""", DateTime.Now, e.PacketSnr, e.PacketRssi, e.Rssi, e.Data.Length, messageText);
#endif
   }
   catch (Exception ex)
   {
      Debug.WriteLine(ex.Message);
   }
}

The addressing implementation needs further testing and I’m building sample .NetMF and *duino clients.

M2M LoRaWan Node Model A328

Along with the M2M LoRaWan Gateway Shield for Raspberry Pi I also purchased a Low power LoRaWan Node Model A328. After setting the Board in Arduino IDE to Arduino pro mini 8Mhz 3V the device fired up and worked first time.

LoRaWanNodeV3_5
The device is intended for LoRaWan applications so the samples provided (including a link to application template generator) were not that applicable for my LoRa project so I used the Arduino LoRa library.

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

byte msgCount = 0;            // count of outgoing messages
int interval = 2000;          // interval between sends
long lastSendTime = 0;        // time of last packet send

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

  Serial.println("LoRa Duplex - Set sync word");

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

  if (!LoRa.begin(915E6)) {             // initialize ratio at 915 MHz
    Serial.println("LoRa init failed. Check your connections.");
    while (true);                       // if failed, do nothing
  }

  LoRa.enableCrc();

  LoRa.setSyncWord(0x12);           // ranges from 0-0xFF, default 0x34, see API docs

  LoRa.dumpRegisters(Serial);
  Serial.println("LoRa init succeeded.");
}

void loop() {
  if (millis() - lastSendTime > interval) {
    String message = "0 Hello Arduino LoRa! ";   // send a message
    message += msgCount;
    sendMessage(message);
    Serial.println("Sending " + message);
    lastSendTime = millis();            // timestamp the message
    //interval = random(2000) + 1000;    // 2-3 seconds
    interval = 1000;
  }

  // parse for a packet, and call onReceive with the result:
  onReceive(LoRa.parsePacket());
}

void sendMessage(String outgoing) {
  LoRa.beginPacket();                   // start packet
  LoRa.print(outgoing);                 // add payload
  LoRa.endPacket();                     // finish packet and send it
  msgCount++;                           // increment message ID
}

void onReceive(int packetSize) {
  if (packetSize == 0) return;          // if there's no packet, return

  // read packet header bytes:
  String incoming = "";

  while (LoRa.available()) {
    incoming += (char)LoRa.read();
  }

  Serial.println("Message: " + incoming);
  Serial.println("RSSI: " + String(LoRa.packetRssi()));
  Serial.println("Snr: " + String(LoRa.packetSnr()));
  Serial.println();
}

I did find the “grove” connectors weren’t compatible with any of my sensors, but the vendor does include a number of cables DIY connection.

GroveConnectorIssue20180822

Next I’ll use power conservation modes and see how long I can get a set of AAA batteries to last. The device looks like a good option (esp. with solar power for devices with higher power consumption sensors) for some of the SmartAg projects my students are building.

In my Windows 10 IoT Core test application I could see the enableCrc() method was working according to the RegHopChannel CrcOnPayload flag.

For real deployments of the field gateway I think packets which have no CRC or a corrupted one will be dropped.