A Node-RED node to receive data from a Bosch BMP085 or BMP180 barometer pressure sensor using I2C interface. Use bmp085 library.
Run command on Node-RED installation directory
npm install node-red-contrib-bmp085
For Raspberry Pi users: enable i2c on your Pi and add pi user to i2c group
Return msg.payload.
msg.payload.temperature - temperature
msg.payload.pressure - pressure
The temperature and pressure units of measurement can be selected as required.
The measured pressure can optionally be corrected to sea level, as used in meteorolgical surface pressure charts, by entering the actual height above sea level of the sensor (US Standard Atmosphere; maximum height 11,000m).
The measurement update interval can also be specified.
Example Node-RED flow:
[{"id":"41f0fc42.bc1834","type":"template","name":"text","field":"payload","template":"Temperature: {{payload.temperature}}°C; Pressure: {{payload.pressure}}mmHg","x":982,"y":626,"z":"c2f61f76.2fd47","wires":[["51c8ed1e.6d326c"]]},{"id":"51c8ed1e.6d326c","type":"debug","name":"","active":true,"console":"false","complete":"payload","x":1174,"y":538,"z":"c2f61f76.2fd47","wires":[]},{"id":"fceb110e.7afd28","type":"bmp085","device":"/dev/i2c-1","timer":"15","pressureUnits":"mmHg","temperatureUnits":"degC","seaLevel":"QFE","height":"NaN","name":"","x":830,"y":727,"z":"c2f61f76.2fd47","wires":[["41f0fc42.bc1834"]]}]