amedeebulle / ttn-mapper

TTN Mapper Arduino Sketch for Adafruit M0 with LoRa radio and OLED display

TTN Mapper node

Introduction

Small sketch to run a TTN Mapper node on an Adafruit Feather M0 Radio with LoRa Radio Module with an OLED FeatherWing.

See https://ttnmapper.org/ for more information about the TTN Mapper project.

Hardware requirements

• Adafruit Feather M0 Radio with LoRa Radio Module
• Adafruit OLED FeatherWing
• Female headers to stack the display on top of the Feather
• Optional: SMT uFL connector, pigtail and antenna
• Battery. Either a small 4.2/3.7V LiPo battery or a 5V source through the MicroUSB connector

To expose the RFM95 DIO1 to the M0, solder a bridge from the IO1 to Digital #11 (or any other free port).
The easiest is to solder this bridge on the FeatherWing.

Software requirements

Aside the Adafruit SAMD support you will need the following libraries:

• For the OLED FeatherWing:
  • Adafruit_SSD1306(1.1.2)
  • Adafruit-GFX-Library (1.2.5)
• For LoRaWan:
  • Arduino LMIC

Running the script

Copy ttn_secrets_template.h to ttn_secrets.h and set your Application Key and App EUI.
You also need to define a unique Device EUI -- as the Adafruit Feather does not have a serial number, take the one automatically generated in the TTN console.

By default, the node sends a message with * as payload every minute.

• You can change the send_packet_interval in ttn_mapper.cpp (Respect duty cycle!)
• To send battery voltage as Cayenne LPP instead of *, uncomment #define CAYENNE_LPP in ttn_mapper.cpp

Compile, upload and you should be good to go!

GPS Tracker and TTN Mapper Integration

To directly send the tracker location to the TTN Mapper integration you can add a GPS module and use the ttn-mapper-gps script.
You will need:

• Adafruit Ultimate GPS featherwing
• Male/Female headers to install the GPS between the MCU and the Display
• GPS antenna and pigtail

And the following libraries:

• Adafruit_GPS (1.0.3)
• Adafruit_ZeroTimer (2.0.0)
• Adafruit_ASFcore

Add the TTN Mapper integration to your application in the TTN Console and configure the Payload decoder with:

function Decoder(bytes, port) {
  // Decode an uplink message from a buffer
  // (array) of bytes to an object of fields.
  var decoded = {};
  if (port === 2) {
    // The port should match the port configured in `ttn_mapper.cpp`
    var i = 0;
    decoded.latitude = (bytes[i++]<<24) + (bytes[i++]<<16) + (bytes[i++]<<8) + bytes[i++];
    decoded.latitude = (decoded.latitude / 1e7) - 90;
    decoded.longitude = (bytes[i++]<<24) + (bytes[i++]<<16) + (bytes[i++]<<8) + bytes[i++];
    decoded.longitude = (decoded.longitude / 1e7) - 180;
    decoded.altitude = (bytes[i++]<<8) + bytes[i++];
    decoded.altitude = decoded.altitude - 0x7fff;
    decoded.hdop = (bytes[i++]<<8) + bytes[i++];
    decoded.hdop = decoded.hdop /10.0;
    if (bytes.length >= 14){
      decoded.voltage = ((bytes[i++]<<8)>>>0) + bytes[i++];
      decoded.voltage /= 100.0;
    }
  }
  return decoded;
}

ttn-mapper's Issues

Update for TTN v3

Hey @AmedeeBulle ! Great write up!

We’ve released a new version of our network server, called The Things Stack. We’re in the process of migrating our user base to the new platform and we will sunset the old environment later this year.

Can I support you updating the documentation to use The Things Stack (i.e. The Things Network v3)? You can start using The Things Stack free of charge by using the Community Edition: https://console.cloud.thethings.network/

Looking forward to hearing from you