pico-bmp280

This is a MicroPython library for the Raspberry Pi Pico and allows communicating with the BMP280 pressure sensor through the SPI and I2C protocols.

SPI Example

from machine import Pin, SPI
from utime import sleep

from bmp280 import BMP280SPI

spi1_sck = Pin(10)
spi1_tx = Pin(11)
spi1_rx = Pin(12)
spi1_csn = Pin(13, Pin.OUT, value=1)
spi1 = SPI(1, sck=spi1_sck, mosi=spi1_tx, miso=spi1_rx)
bmp280_spi = BMP280SPI(spi1, spi1_csn)

while True:
    readout = bmp280_spi.measurements
    print(f"Temperature: {readout['t']} °C, pressure: {readout['p']} hPa.")
    sleep(1)

This is the circuit for the example code above. It uses the Adafruit BMP280 breakout board.

I2C Example

from machine import Pin, I2C
from utime import sleep

from bmp280 import BMP280I2C

i2c0_sda = Pin(8)
i2c0_scl = Pin(9)
i2c0 = I2C(0, sda=i2c0_sda, scl=i2c0_scl, freq=400000)
bmp280_i2c = BMP280I2C(0x77, i2c0)  # address may be different

while True:
    readout = bmp280_i2c.measurements
    print(f"Temperature: {readout['t']} °C, pressure: {readout['p']} hPa.")
    sleep(1)

Customizing configuration

The default settings use the weather monitoring settings as specified by Bosch in the datasheet (see table 15 on page 19). The configuration can be changed by overriding the defaults set in BMP280Configuration.

The next example configures the BMP280 for indoor navigation:

from bmp280 import BMP280I2C, BMP280Configuration

config = BMP280Configuration()
config.power_mode = BMP280Configuration.POWER_MODE_NORMAL
config.pressure_oversampling = BMP280Configuration.PRESSURE_OVERSAMPLING_16X
config.temperature_oversampling = BMP280Configuration.TEMPERATURE_OVERSAMPLING_2X
config.filter_coefficient = BMP280Configuration.FILTER_COEFFICIENT_16
config.standby_time = BMP280Configuration.STANDBY_TIME__5_MS

bmp280_i2c = BMP280I2C(0x77, i2c0, config)