ESP32 and BMP180 sensor example

This bmp180 from Bosch is the best low-cost sensing solution for measuring barometric pressure and temperature. The sensor is soldered onto a PCB with a 3.3V regulator, I2C level shifter and pull-up resistors on the I2C pins. The BMP180 replaces the BMP085.

Specification

• Pressure sensing range: 300-1100 hPa (9000m to -500m above sea level)
• Up to 0.03hPa / 0.25m resolution
• -40 to +85°C operational range, +-2°C temperature accuracy

Here is a breakout which makes it easy to use the sensor. The sensor will cost less than $2.

BMP180 breakout

Parts Required

Here are the parts I used

Name	Link
ESP32		Aliexpress link Amazon Ebay
bmp180		Aliexpress link Ebay link Amazon Link
Connecting cables		Aliexpress link Amazon Ebay

Layout

Make the following connections, this is a Wemos Lolin32, you may have to make small changes for other ESP32 boards.

lolin32 and bmp180

Code

You will need the Adafruit BMP085 library for this example, you can either download it or use the library manager in newer Arduino IDEs.

https://github.com/adafruit/Adafruit-BMP085-Library

In this example I am only looking at the temperature and pressure but there are other functions in the library

#include <Wire.h>
#include <Adafruit_BMP085.h>

Adafruit_BMP085 bmp;

void setup()
{
Serial.begin(9600);
//Wire.begin (4, 5);
if (!bmp.begin())
{
Serial.println("Could not find BMP180 or BMP085 sensor at 0x77");
while (1) {}
}
}

void loop()
{
Serial.print("Temperature = ");
Serial.print(bmp.readTemperature());
Serial.println(" Celsius");

Serial.print("Pressure = ");
Serial.print(bmp.readPressure());
Serial.println(" Pascal");

Serial.println();
delay(5000);
}

Output

Open the Serial monitor and you should see something like this

Temperature = 19.80 Celsius
Pressure = 100831 Pascal

Temperature = 19.80 Celsius
Pressure = 100829 Pascal

Temperature = 19.70 Celsius
Pressure = 100825 Pascal

Temperature = 19.70 Celsius
Pressure = 100834 Pascal