ESP32 and DS18B20 only works once after upload

Official Hardware Nano Family Nano ESP32
1

Good day all,

I have a really odd issue and I would love some help on this odd one.
I have a ESP32 board, with a DS18B20 connected on pin D4, which I believe on the ESP references pin 7.
Once I Upload after setting the pin to 7, the DS18B20 works perfectly, until I either re-upload or plug the ESP32 in elsewhere where it is actually being used. Basically if it reboots once, it tickets. I then have to change the pin, to lets say 4, upload, then change it back to 7, upload and it works again until unplugged...

I am powering the ESP over USB C and only have 2 DS18B20's connected in serial. I have tested with only 1 DS18B20 and get the same behavior.
I am using a Gikfun DS18B20 : Gikfun DS18B20 Waterproof Digital Temperature Sensor with Adapter Module for Arduino (Pack of 3 Sets) EK1183 : Amazon.ca: Industrial & Scientific

51dLr5fPn3L.SL1001
51dLr5fPn3L.SL10011001×1001 55.3 KB

My Code is as follows:

//Network Connectivity
#include <WiFi.h>
#include <HTTPClient.h>
#include "arduino_secrets.h" 
//Temp Probe
#include <OneWire.h>
#include <DallasTemperature.h>
#define ONE_WIRE_BUS 7
OneWire oneWire(ONE_WIRE_BUS);
DallasTemperature sensors(&oneWire);

//Temp Sensor DS18B20
//Black = GND
//Yellow = Data
//White = VCC

const char* password = "Password";
const char* ssid = "WIFINetwork";
int SensorID1 = 4;
float TempS1 = 0;
int SensorID2 = 5;
float TempS2 = 0;
int SensorID3 = 6;//NA
float TempS3 = 0;

// API endpoint
const char* serverName = "http://192.168.10.xxxx";

// Timing variables
unsigned long lastTime = 0;
const unsigned long interval = 30000; // 1 minute in milliseconds = 30000

void setup() {
  Serial.begin(115200);
  pinMode(motorPin1, OUTPUT);
  pinMode(motorPin2, OUTPUT);
  pinMode(buttonOpen, INPUT_PULLUP);
  pinMode(buttonClose, INPUT_PULLUP);

  // Connect to Wi-Fi
  Serial.print("Connecting to Wi-Fi");
  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(1000);
    Serial.print(".");
  }
  Serial.println("\nConnected to Wi-Fi");

  sensors.begin();  // Start up the Temperature library
  TempS1 = sensors.getTempCByIndex(0);
}

void loop() {
  // Check if it's time to send the PUT request
  unsigned long currentTime = millis();
  if (currentTime - lastTime >= interval) {
    lastTime = currentTime;

    ReadTemps();

    if (WiFi.status() == WL_CONNECTED) {
      
      // Prepare JSON payload
      float value = TempS1;
      int sensorid = SensorID1;
      Serial.println("Temperature 1 : " + String(value));
      PostTemps(value, sensorid);

      value = TempS2;
      sensorid = SensorID2;
      Serial.println("Temperature 2 : " + String(value));
      PostTemps(value, sensorid);

      value = TempS3;
      sensorid = SensorID3;
      Serial.println("Temperature 3 : " + String(value));
      PostTemps(value, sensorid);
    } else {
        Serial.println("WiFi Disconnected");
      }
  }
  delay(100);
}

void PostTemps(float value, int sensorid) {

      WiFiClient client;
      HTTPClient http;
      http.begin(client, serverName);

      // Add headers
      http.addHeader("Content-Type", "application/json; charset=utf-8");
      http.addHeader("accept", "*/*");

  if(value != -127)
      {
        String jsonPayload = "{\"value\": " + String(value) + ", \"sensorid\": " + String(sensorid) + "}";

        // Send POST request
        int httpResponseCode = http.POST(jsonPayload);


        // Handle response
        if (httpResponseCode > 0) {
          String payload = http.getString(); // Get response payload
          Serial.println("HTTP Response code: " + String(httpResponseCode));
          Serial.println("Response: " + payload);
        } else {
          Serial.println("Error on HTTP request");
          Serial.println("Server: " + String(serverName));
          Serial.println("Payload: " + jsonPayload);

        http.end(); // Free resources
      }
    }
}

void ReadTemps() {
  sensors.requestTemperatures();

  // You can have more than one IC on the same bus. 0 refers to the first IC on the wire
  TempS1 = sensors.getTempCByIndex(0);
  TempS2 = sensors.getTempCByIndex(1);
  TempS3 = sensors.getTempCByIndex(2);
}

Apologies if I have missed anything.
Thank you

2

You need to pick another pin, Gpio7 is connected to Esp32 boards flash memory.
Choose any pin between 16-33 for example.

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