ESP32, relay and DS18B20 probe

Hi, I was wondering if someone can assist me with a Blynk code to switch on the relay when it is at a certain temperature and switch off at a certain temperature?

I am using the following hardware, ESP32, 5v Relay, and DS18B20 Temperature Probe. Using it with the Blynk app over wifi.

I do not have any coding experience. Newbie

You can search the forum for a working sketch first.

I have found something in the forum, but it is to much code for what I want to do. As I do not know coding, I do not know what pieces of code to take out of the code I found.

The forum isn’t a code factory.

I’m sure if you searched you’d find some examples.
Also, watching some YouTube videos on C++ coding basics will give you a much better understanding of what you need to do to achieve your goals.


try this sketch first :

#include <WiFi.h>
#include <WiFiClient.h>
#include <BlynkSimpleEsp32.h>
#include <OneWire.h>
#include <DallasTemperature.h>
#define BLYNK_PRINT Serial    // Comment this out to disable prints and save space
char auth[] = "";
/* WiFi credentials */
char ssid[] = "";
char pass[] = "";
BlynkTimer timer;
 // Data wire is connected to pin 21
#define ONE_WIRE_BUS 21

OneWire oneWire(ONE_WIRE_BUS);
DallasTemperature DS18B20(&oneWire);
float temp;
float Fahrenheit=0;

void getdata()
  temp = DS18B20.getTempCByIndex(0); // Celcius
   Fahrenheit = DS18B20.toFahrenheit(temp); // Fahrenheit
  Blynk.virtualWrite(V3, temp); //virtual pin V3
  Blynk.virtualWrite(V4, Fahrenheit); //virtual pin V4

void setup() 
  Blynk.begin(auth, ssid, pass);
  timer.setInterval(1000L, getdata);
void loop() 

Thank you very much John93. I really appreciate it.

I understand this is not a coding factory and I will try my best to self educate with research.

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