Barometer
Measures atmospheric pressure and calculates altitude using I2C barometric sensors.
Overview
Barometric pressure sensors measure the atmospheric pressure around them, which can be used to determine altitude, predict weather changes, or monitor environmental conditions. ArduinoStudio supports popular I2C barometers including the BMP180, BMP085, and MPL3115A2.
The component emits sensor-data events with pressure (in hPa/mbar) and calculated altitude (in meters).
Supported Sensors
| Sensor | Pressure Range | Accuracy | Voltage |
|---|---|---|---|
| BMP180 | 300 – 1100 hPa | +-0.12 hPa | 3.3V only |
| BMP085 | 300 – 1100 hPa | +-0.25 hPa | 3.3V only |
| MPL3115A2 | 200 – 1100 hPa | +-0.4 hPa | 3.3 – 5V |
Wiring Guide
| Sensor Pin | Arduino Pin |
|---|---|
| VCC | 3.3V (BMP180/085) or 3.3–5V (MPL3115A2) |
| GND | GND |
| SDA | A4 (Uno) / 20 (Mega) |
| SCL | A5 (Uno) / 21 (Mega) |
Important: The BMP180 and BMP085 are 3.3V sensors. Do not connect VCC to the 5V pin — it can damage the sensor. If your breakout board has a built-in voltage regulator, check the board documentation.
Altitude Calculation
Altitude is derived from pressure using the barometric formula. For accurate readings, you should set the sea-level pressure reference for your location (standard is 1013.25 hPa). The BMP180 achieves altitude resolution of approximately 0.17 meters.
Usage in ArduinoStudio
Drag the Barometer component onto the canvas. It automatically uses the I2C bus (A4/A5 on Uno). Pressure and altitude readings stream continuously. Use threshold triggers to alert on pressure changes — for example, detect rapid altitude changes in a drone project.