Displaying the sensor readings on the serial port

In this activity we will be writing the code to display the sensor reading from DS18B20 and displaying them on the serial port via the Arduino IDE

The Code

Upload the following code on the Arduino IDE

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

// GPIO where the DS18B20 is connected to
const int oneWireBus = 4;     

// Setup a oneWire instance to communicate with any OneWire devices
OneWire oneWire(oneWireBus);

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

void setup() {
  // Start the Serial Monitor
  Serial.begin(115200);
  // Start the DS18B20 sensor
  sensors.begin();
}

void loop() {
  sensors.requestTemperatures(); 
  float temperatureC = sensors.getTempCByIndex(0);
  float temperatureF = sensors.getTempFByIndex(0);
  Serial.print(temperatureC);
  Serial.println("ºC");
  Serial.print(temperatureF);
  Serial.println("ºF");
  delay(5000);
}

Explaining the Code:

The first you need to is to include the two libraries: OneWire and DallasTemperature:

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

Next you need to declare the GPIO pin that the DS18B20 is connected to:

// GPIO where the DS18B20 is connected to
const int oneWireBus = 4;
// Setup a oneWire instance to communicate with any OneWire devices
OneWire oneWire(oneWireBus);
// Pass our oneWire reference to Dallas Temperature sensor 
DallasTemperature sensors(&oneWire);

Then in the setup section you initialise the serial monitor at a baud rate of 115200

Serial.begin(115200);

Initialise the DS18B20 sensor:

sensors.begin();

To receive the temperature readings you need to call the requestTemperatures() method as follows:

sensors.requestTemperatures(); 

To get the temperature in the metric unit Celsius add the following method:

float temperatureC = sensors.getTempCByIndex(0);

If you prefer to get it in Fahrenheit, use the following method:

float temperatureF = sensors.getTempFByIndex(0);

The final step is to print the temperature readings in the serial monitor. The readings will be requested every 5 seconds:

Serial.print(temperatureC);
Serial.println("ºC");
Serial.print(temperatureF);
Serial.println("ºF");

delay(5000);

Upload the code and open the serial monitor to see the temperature readings.