Interfacing BMP180 Digital Pressure Sensor With Arduino

Introduction

In the world of electronics, sensors play a vital role in capturing and measuring physical parameters such as temperature, humidity, pressure, and more. Pressure sensors are widely used in various applications, from automotive to weather monitoring. The BMP180 digital pressure sensor is one of the most popular and affordable pressure sensors available on the market today.

In this article, we will discuss how to interface the “BMP180 sensor” with Arduino and how to read the pressure and temperature data from it.

What is BMP180 Digital Pressure Sensor?

The BMP180 digital pressure sensor is a highly accurate and low-cost sensor that can measure both barometric pressure and temperature. It is manufactured by Bosch and is widely used in various electronic applications, including weather forecasting, altitude measurement, and GPS systems. The sensor works based on the principle of piezoresistive pressure measurement, where changes in pressure cause the resistance of a sensor to change. The BMP180 sensor is compact in size and can communicate with microcontrollers such as Arduino using the I2C communication protocol. It has a measurement range of 300 to 1100 hPa (hectopascals) and can provide temperature readings with a resolution of 0.1°C. Its high accuracy, low power consumption, and small form factor make it an ideal choice for various projects that require pressure and temperature monitoring.

Hardware Components

To interface a BMP180 Digital Pressure Sensor with Arduino, you’ll need the following hardware components to get started:

Components	Value	Qty
Arduino UNO	–	1
USB Cable Type A to B	–	1
DC Power for Arduino	–	1
sensor	BMP180	1
Breadboard	–	1
Jumper Wires	–	1

BMP180 Digital Pressure Sensor Pinout

Pin Name	Pin Description
VIN	Input supply voltage. The range is 3 V to 5 V
3V0	3 V pin out from the regulator
GND	Ground pin. Connect this to Arduino GND pin
SCL	I2C Clock line (Serial CLock)
SDA	I2C Data line (Serial Data)

BMP180 Digital Pressure Sensor Circuit

Make connections according to the circuit diagram given below.

Wiring / Connections

Arduino	BMP180 sensor
5V	VCC
GND	GND
A4	SDA
A5	SCL

Installing Arduino IDE

First, you need to install Arduino IDE Software from its official website Arduino. Here is a simple step-by-step guide on “How to install Arduino IDE“.

Installing Libraries

Before you start uploading a code, download and unzip the following libraries at /Program Files(x86)/Arduino/Libraries (default), in order to use the sensor with the Arduino board. Here is a simple step-by-step guide on “How to Add Libraries in Arduino IDE“.

• Adafruit_BMP085.h

Code

Now copy the following code and upload it to Arduino IDE Software.

#include <Adafruit_BMP085.h>
 
Adafruit_BMP085 bmp;
 
void setup() {
  Serial.begin(9600);
  if (!bmp.begin()) {
  Serial.println("Could not find a valid BMP085 sensor, check wiring!");
  while (1) {}
  }
}
 
void loop() {
    Serial.print("Temperature = ");
    Serial.print(bmp.readTemperature());
    Serial.println(" *C");
   
    Serial.print("Pressure = ");
    Serial.print(bmp.readPressure());
    Serial.println(" Pa");
   
    // Calculate altitude assuming 'standard' barometric
    // pressure of 1013.25 millibar = 101325 Pascal
    Serial.print("Altitude = ");
    Serial.print(bmp.readAltitude());
    Serial.println(" meters");
 
    Serial.print("Pressure at sealevel (calculated) = ");
    Serial.print(bmp.readSealevelPressure());
    Serial.println(" Pa");
 
  // you can get a more precise measurement of altitude
  // if you know the current sea level pressure which will
  // vary with weather and such. If it is 1015 millibars
  // that is equal to 101500 Pascals.
    Serial.print("Real altitude = ");
    Serial.print(bmp.readAltitude(101500));
    Serial.println(" meters");
   
    Serial.println();
    delay(500);
}void setup() {
  // put your setup code here, to run once:
 
}
 
void loop() {
  // put your main code here, to run repeatedly:
 
}

Code Explanation

This Arduino code uses the Adafruit_BMP085 library to interface the BMP180 digital pressure sensor with the Arduino microcontroller. The code starts by including the necessary library and creating an instance of the Adafruit_BMP085 class named bmp.

In the setup function, the code initializes the serial communication and checks whether the sensor is connected to the Arduino by calling the bmp.begin() function. If the sensor is not found, the program enters an infinite loop and displays an error message on the serial monitor.

In the loop function, the code reads the temperature, pressure, altitude, and pressure at sea level data from the BMP180 sensor by calling the corresponding functions provided by the library. It then displays the data on the serial monitor using the Serial.print() and Serial.println() functions. The delay(500) function is used to introduce a 500-millisecond delay between each set of readings to avoid overloading the serial monitor.

Overall, this code demonstrates how to interface the BMP180 sensor with an Arduino and read the data from it. It can be used as a starting point for building more advanced projects that require pressure and temperature sensing.

Applications

Here are some applications of the BMP180 digital pressure sensor:

• Weather monitoring systems
• Altitude measurement devices
• GPS navigation systems
• Drones and unmanned aerial vehicles (UAVs)
• Barometric pressure sensors for indoor navigation and positioning
• Automotive tire pressure monitoring systems
• Industrial pressure measurement and control systems
• Medical devices such as ventilators and blood pressure monitors
• Aerospace applications such as altitude and airspeed measurement in airplanes and rockets.

Conclusion

Interfacing the BMP180 digital pressure sensor with Arduino is a straightforward process, and it opens up a vast range of possibilities for pressure monitoring applications. The BMP180 sensor’s compact size, low cost, and high accuracy make it an ideal choice for various projects, from weather monitoring systems to altitude measurement devices.