ESP32 - Temperature Sensor - LCD

Hardware Required

1×ESP-WROOM-32 Dev Module
1×Micro USB Cable
1×LCD I2C
1×Temperature Sensor DS18B20
1×4.7 kΩ resistor
1×Breadboard
n×Jumper Wires
Please note: These are affiliate links. If you buy the components through these links, We may get a commission at no extra cost to you. We appreciate it.

About Temperature Sensor and LCD

If you do not have knowledge of temperature sensor and LCD (pinout, how they work, how to connect them to ESP32, how to program for them...), learn about them in the following tutorials:

Wiring Diagram

  • Wiring diagram
  • ESP32 Temperature Sensor LCD Wiring Diagram

    Image is developed using Fritzing. Click to enlarge image

ESP32 Code

/* * Created by esp32io.com * * This example code is in the public domain * * Tutorial page: https://esp32io.com/tutorials/esp32-temperature-sensor-lcd */ #include <OneWire.h> #include <DallasTemperature.h> #include <LiquidCrystal_I2C.h> const int SENSOR_PIN = 13; // ESP32 pin connected to DS18B20 sensor's DQ pin OneWire oneWire(SENSOR_PIN); // setup a oneWire instance DallasTemperature sensors(&oneWire); // pass oneWire to DallasTemperature library LiquidCrystal_I2C lcd(0x3F, 16, 2); // I2C address 0x27, 16 column and 2 rows float tempCelsius; // temperature in Celsius float tempFahrenheit; // temperature in Fahrenheit void setup() { sensors.begin(); // initialize the sensor lcd.init(); // initialize the lcd lcd.backlight(); // open the backlight } void loop() { sensors.requestTemperatures(); // send the command to get temperatures tempCelsius = sensors.getTempCByIndex(0); // read temperature in Celsius tempFahrenheit = tempCelsius * 9 / 5 + 32; // convert Celsius to Fahrenheit lcd.clear(); lcd.setCursor(0, 0); // start to print at the first row lcd.print(tempCelsius); // print the temperature in Celsius lcd.print((char)223); // print ° character lcd.print("C"); lcd.setCursor(0, 1); // start to print at the second row lcd.print(tempFahrenheit); // print the temperature in Fahrenheit lcd.print((char)223); // print ° character lcd.print("F"); delay(500); }

Quick Steps

On Arduino IDE, Go to Tools Manage Libraries

ESP32 add library
  • Search “OneWire”, then find the OneWire library by Paul Stoffregen
  • Click Install button to install OneWire library.
  • ESP32 onewire library
  • Search “Dallas”, then find the DallasTemperature library by Miles Burton.
  • Click Install button to install DallasTemperature library.
  • ESP32 Dallas Temperature library
  • Search “LiquidCrystal I2C”, then find the LiquidCrystal_I2C library by Frank de Brabander
  • Click Install button to install LiquidCrystal_I2C library.
  • ESP32 LiquidCrystal I2C library
  • Copy the above code and paste it to Arduino IDE
  • Click Upload button on Arduino IDE to compile and upload code to ESP32 board
  • Arduino IDE Upload Code
  • Put the sensor on hot and cold water, or grasp the sensor by your hand
  • See the result in LCD

If LCD displays nothing, see Troubleshooting on LCD I2C

Code Explanation

Read the line-by-line explanation in comment lines of source code!

Video Tutorial

We are considering to make the video tutorials. If you think the video tutorials are essential, please subscribe to our YouTube channel to give us motivation for making the videos.

Temperature Sensor and LCD on Commercial Products

※ NOTE THAT:

Note that this tutorial is incomplete. We will post on our Facebook Page when the tutorial is complete. Like it to get updated.

※ NOTICES

  • We are AVAILABLE for HIRE. See how to hire us to do your project
  • If this tutorial is useful for you, please support us to make more tutorials.
  • We spent a lot of time and effort to create the content for this tutorial, please respect our work! Please do not copy the content to share on other websites. Howerver, please feel free to share the link of this tutorial anywhere