[SOLVED] ESP32 LoRa V2 to TTN with Dallas Temp Probe - appData encoding

I am having trouble figuring out how to send temperature data to TTN. The ESP32 joins successfully and the device client attributes update successfully everytime it sends data, but I’m unable to figure out how to send the temperature data.

The telemetry data never receives anything.

I’m using this [https://github.com/HelTecAutomation/ESP32_LoRaWAN/tree/8c1f98f8305d0d328051e71b51d865cccab632d3](http://version of ESP32_LoRaWAN )

/*
 * HelTec Automation(TM) LoRaWAN 1.0.2 OTAA example use OTAA, CLASS A
 *
 * Function summary:
 *
 * - use internal RTC(150KHz);
 *
 * - Include stop mode and deep sleep mode;
 *
 * - 15S data send cycle;
 *
 * - Informations output via serial(115200);
 *
 * - Only ESP32 + LoRa series boards can use this library, need a license
 *   to make the code run(check you license here: http://www.heltec.cn/search);
 *
 * You can change some definition in "Commissioning.h" and "LoRaMac-definitions.h"
 *
 * HelTec AutoMation, Chengdu, China.
 * 成都惠利特自动化科技有限公司
 * https://heltec.org
 * support@heltec.cn
 *
 *this project also release in GitHub:
 *https://github.com/HelTecAutomation/ESP32_LoRaWAN
*/

#include <ESP32_LoRaWAN.h>
#include "Arduino.h"
#include <OneWire.h>
#include <DallasTemperature.h>

// Data wire is plugged into port 13 on the Arduino
#define ONE_WIRE_BUS 13

// Setup a oneWire instance to communicate with any OneWire devices (not just Maxim/Dallas temperature ICs)
OneWire oneWire(ONE_WIRE_BUS);

// Pass our oneWire reference to Dallas Temperature. 
DallasTemperature sensors(&oneWire);


/*license for Heltec ESP32 LoRaWan, quary your ChipID relevant license: http://resource.heltec.cn/search */
uint32_t  license[4] = {0xC1670CF8, 0x19C71AD5, 0x6CE47540, 0x8CF267EC};
/* OTAA para*/
uint8_t DevEui[] = { 0x22, 0x32, 0x33, 0x00, 0x00, 0x88, 0x88, 0x02 };
uint8_t AppEui[] = { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };
uint8_t AppKey[] = { 0x88, 0x88, 0x88, 0x88, 0x88, 0x88, 0x88, 0x88, 0x88, 0x88, 0x88, 0x88, 0x88, 0x88, 0x66, 0x01 };

/* ABP para*/
uint8_t NwkSKey[] = { 0x15, 0xb1, 0xd0, 0xef, 0xa4, 0x63, 0xdf, 0xbe, 0x3d, 0x11, 0x18, 0x1e, 0x1e, 0xc7, 0xda,0x85 };
uint8_t AppSKey[] = { 0xd7, 0x2c, 0x78, 0x75, 0x8c, 0xdc, 0xca, 0xbf, 0x55, 0xee, 0x4a, 0x77, 0x8d, 0x16, 0xef,0x67 };
uint32_t DevAddr =  ( uint32_t )0x007e6ae1;

/*LoraWan Class, Class A and Class C are supported*/
DeviceClass_t  loraWanClass = CLASS_A;

/*the application data transmission duty cycle.  value in [ms].*/
uint32_t appTxDutyCycle = 15000;

/*OTAA or ABP*/
bool overTheAirActivation = true;

/*ADR enable*/
bool loraWanAdr = true;

/* Indicates if the node is sending confirmed or unconfirmed messages */
bool isTxConfirmed = true;

/* Application port */
uint8_t appPort = 2;

/*!
* Number of trials to transmit the frame, if the LoRaMAC layer did not
* receive an acknowledgment. The MAC performs a datarate adaptation,
* according to the LoRaWAN Specification V1.0.2, chapter 18.4, according
* to the following table:
*
* Transmission nb | Data Rate
* ----------------|-----------
* 1 (first)       | DR
* 2               | DR
* 3               | max(DR-1,0)
* 4               | max(DR-1,0)
* 5               | max(DR-2,0)
* 6               | max(DR-2,0)
* 7               | max(DR-3,0)
* 8               | max(DR-3,0)
*
* Note, that if NbTrials is set to 1 or 2, the MAC will not decrease
* the datarate, in case the LoRaMAC layer did not receive an acknowledgment
*/
uint8_t confirmedNbTrials = 8;

/*LoraWan debug level, select in arduino IDE tools.
* None : print basic info.
* Freq : print Tx and Rx freq, DR info.
* Freq && DIO : print Tx and Rx freq, DR, DIO0 interrupt and DIO1 interrupt info.
* Freq && DIO && PW: print Tx and Rx freq, DR, DIO0 interrupt, DIO1 interrupt, MCU sleep and MCU wake info.
*/
uint8_t debugLevel = LoRaWAN_DEBUG_LEVEL;

/*LoraWan region, select in arduino IDE tools*/
LoRaMacRegion_t loraWanRegion = ACTIVE_REGION;


static void prepareTxFrame( uint8_t port )
{
    Serial.print("Requesting temperatures...");
    sensors.requestTemperatures(); // Send the command to get temperatures
    float Temperature = (float)(sensors.getTempCByIndex(0));    
    unsigned char *puc;
    puc = (unsigned char *)(&Temperature);
    
    appDataSize = 5;//AppDataSize max value is 64
    appData[0] = puc[0];
    appData[1] = puc[1];
    appData[2] = puc[2];
    appData[3] = puc[3];
    appData[4] = puc[4];

    Serial.print("Temperature for the device 1 (index 0) is: ");
    Serial.println(Temperature);  
}

// Add your initialization code here
void setup()
{
    // locate devices on the bus
  Serial.print("Locating devices...");
  sensors.begin();
  if(mcuStarted==0)
  {
    LoRaWAN.displayMcuInit();
  }
  Serial.begin(115200);
  while (!Serial);
  SPI.begin(SCK,MISO,MOSI,SS);
  Mcu.init(SS,RST_LoRa,DIO0,DIO1,license);
  deviceState = DEVICE_STATE_INIT;

  Serial.print("Found ");
  Serial.print(sensors.getDeviceCount(), DEC);
  Serial.println(" devices.");
}

// The loop function is called in an endless loop
void loop()
{

  switch( deviceState )
  {
    case DEVICE_STATE_INIT:
    {
      LoRaWAN.init(loraWanClass,loraWanRegion);
      break;
    }
    case DEVICE_STATE_JOIN:
    {
      LoRaWAN.displayJoining();
      LoRaWAN.join();
      break;
    }
    case DEVICE_STATE_SEND:
    {
      LoRaWAN.displaySending();
      prepareTxFrame( appPort );
      LoRaWAN.send(loraWanClass);
      deviceState = DEVICE_STATE_CYCLE;
      break;
    }
    case DEVICE_STATE_CYCLE:
    {
      // Schedule next packet transmission
      txDutyCycleTime = appTxDutyCycle + randr( -APP_TX_DUTYCYCLE_RND, APP_TX_DUTYCYCLE_RND );
      LoRaWAN.cycle(txDutyCycleTime);
      deviceState = DEVICE_STATE_SLEEP;
      break;
    }
    case DEVICE_STATE_SLEEP:
    {
      LoRaWAN.displayAck();
      LoRaWAN.sleep(loraWanClass,debugLevel);
      break;
    }
    default:
    {
      deviceState = DEVICE_STATE_INIT;
      break;
    }
  }
}

`

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Just updated a document:
https://heltec-automation-docs.readthedocs.io/en/latest/general/decode_payload.html

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