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