BME280 Environment sensor

This module reads values from Bosch Sensortec's BME280 sensor. Use the BME280 module for it.

Note: There is also a BMP280 module, which doesn't include the humidity calculations (which can save a little code space).

Wiring

You can wire this up as follows:

Don't forget to pull-up both of the I2C pins with 10k resistors.

Software

Simple SPI

var spi = new SPI();
spi.setup({miso : ..., mosi : ..., sck: ...});
var bme = require("BME280").connectSPI(spi, cs_pin);
console.log(bme.getData());
// prints { "temp": 23.70573815741, "pressure": 1017.27733597036, "humidity": 42.0771484375 }

Simple I2C

I2C1.setup({scl:B8,sda:B9});
var bme = require("BME280").connect(I2C1);
console.log(bme.getData());
// prints { "temp": 23.70573815741, "pressure": 1017.27733597036, "humidity": 42.0771484375 }

Simple I2C (with Alternative I2C address)

I2C1.setup({scl:B8,sda:B9});
var bme = require("BME280").connect(I2C1,{addr: 0x77});  // use alternate I2C address
console.log(bme.getData());
// prints { "temp": 23.70573815741, "pressure": 1017.27733597036, "humidity": 42.0771484375 }

Manual usage

Sometimes you might want to read the raw data in separately, in which case you can do:

  I2C1.setup({scl:B8,sda:B9});
  var bme = require("BME280").connect(I2C1);
  bme.readRawData();
  var temp_cal = bme.calibration_T(bme.temp_raw);
  var press_cal = bme.calibration_P(bme.pres_raw);
  var hum_cal = bme.calibration_H(bme.hum_raw);
  var temp_act = temp_cal / 100.0;
  var press_act = press_cal / 100.0;
  var hum_act = hum_cal / 1024.0;

  console.log("Pressure: " + press_act + " hPa");
  console.log("Temperature: " + temp_act + " C");
  console.log("Humidity: "+ hum_act+" %");