Overview
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README
This is a driver for the Bosch BME280 temperature/pressure/humidity sensor, for use with MicroPython-based boards.
About the BME280
The Bosch BME280 Environmental Sensor is a combined temperature, pressure and humidity sensor. It can communicate via I2C or SPI; this driver uses I2C.
See the datasheet at https://www.adafruit.com/datasheets/BST-BME280_DS001-10.pdf for details.
Using the library
Use ftp to copy bme280.py
to the flash
or flash/lib
directory on the board. Then:
import machine import bme280 i2c = machine.I2C(0, pins=('GP11', 'GP10')) bme = bme280.BME280(i2c=i2c) print(bme.temperature, bme.pressure, bme.humidity)
Detailed usage
The temperature
, pressure
and humidity
properties are convenience functions that provide human-readable string values to quickly check that the sensor is working. In practice, the methods to use are:
get_temperature()
: returns the temperature in hundredths of a degree celsius. For example, the value 2534 indicates a temperature of 25.34 degrees.get_pressure()
: returns the atmospheric pressure. This 32-bit value consists of 24 bits indicating the integer value, and 8 bits indicating the fractional value. To get a value in Pascals, divide the return value by 256. For example, a value of 24674867 indicates 96386.2Pa, or 963.862hPa.get_humidity()
: returns the relative humidity. This 32-bit value consists of 22 bits indicating the integer value, and 10 bits indicating the fractional value. To get a value in %RH, divide the return value by 1024. For example, a value of 47445 indicates 46.333%RH.