Let's Workshop: LC Technology RW1820 Temperature Sensor Module

Here is a quick introduction to using the LC Technology RW1820 temperature module. We aim to provide you with the tools you require to start measuring temperatures.

This example will demonstrate the use of an Arduino UNO in requesting and interpreting data from a RW1820 sensor module. Once connected and the first program loaded, the serial monitor will display a live temperature readout. This will use the OneWire library created by Paul Stoffregen and the DallasTemperature library created by Miles Burton.

Components

• 1pcs Arduino UNO or Compatible - LCAA100005
• 1pcs LC Technology RW1820 Temperature Sensor Module - BDAA100146
• 3pcs Male to Female Jumper Cables - GBAA100002

Wiring

Wire the two boards together as can be seen in the image below, taking care to match the pin numbers.

Coding

The code consists of the an include, definition, launch, setup and loop. First the OneWire library and the DallasTemperature library are linked to the code. The sensor pin is defined followed by the OneWire library and DallasTemperature library instances established. The setup launches the serial connection and sensor connection. The loop contains the control program that will run continuously after the setup. It begins by requesting the information from the sensor instance. It then prints the value to the serial monitor.

Load the code below into the Arduino IDE and upload it to your board.

/*
  A simple program designed to setup and demonstrate the DallasTemperature library and 
  RW1820 TEMPERATURE SENSOR MODULE - BDAA100146

  The program uses the OneWire and DallasTemperature libraries to request and 
  ouput temperatures from a RW1820 sensor to the serial monitor.
  
  modified 15 February 2019
  by Sebastian Karam - Flux Workshop
  
  The OneWire library created by Paul Stoffregen
  https://github.com/PaulStoffregen/OneWire

  The DallasTemperature library created by Miles Burton
  https://github.com/milesburton/Arduino-Temperature-Control-Library
*/ 

#include <OneWire.h>
#include <DallasTemperature.h>

// Define the pin that the sensor pin
#define ONE_WIRE_BUS 2

// Establish a oneWire instance
OneWire oneWire(ONE_WIRE_BUS);

// Establish Dallas Temperature instance
DallasTemperature sensors(&oneWire);

void setup(void)
{
  Serial.begin(9600); // Open a serial communication line
  sensors.begin(); // Start up the DallasTemperature library
}

void loop(void){ 
  sensors.requestTemperatures(); // Request temperatures from the sensors instance
  Serial.print("Temperature (Celcius): "); // Print to the serial monitor
  Serial.print(sensors.getTempCByIndex(0)); // Print the temperature from the library to serial monitor
  Serial.print("\n"); // Print to the serial monitor
  delay(1000); // Pause before restarting the loop
}

Running

With the board loaded with the program and all the connections made the module will begin to output a temperature in Celsius. The animation below shows a brief loop of the sensor being placed under a hot cup of water.

What to try next?

• Using multiple temperature sensors - changing the number "0" in "sensors.getTempCByIndex(0)"
• Use the DallasTemperature library to produce the output in Fahrenheit.