BMP180 based USB atmospheric pressure monitor

We initially developed this USB atmospheric pressure monitor to study some operating characteristics of Bosch BMP180 sensor. BMP180 is a low-cost sensor for measuring barometric pressure and temperature. According to the datasheet this sensor can use to measure pressure ranging between 300hPa to 1100hPa. This sensor is introduced a couple of years back but still, it is popular due to lower cost and simplicity of its interface.

BMP180 based sensor module

We did this unit to test the BMP180 sensor more accurately and to study its behaviors. This unit is based on PIC18F2550 microcontroller and the main reason to select this MCU is because of its built-in USB 2.0 interface.

BMP180 sensor monitor application

To display sensor calibration data and it’s readings we did small windows application. This application display and plot temperature and pressure readings captured from the BMP180 sensor.

This unit is programmed to work as a USB HID device and no special device driver is required to use this device. We test this unit in Windows 10 environment.

All the schematics, firmware files and source codes of this project are available at https://github.com/dilshan/bmp180-monitor.

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