History

Phil Howard 6a3ba0d421 MicroPython: Shim MP_REGISTER_MODULE for >1.18 compat. MicroPython has changed MP_REGISTER_MODULE to use only two args and now runs the preprocessing stage on files before running makemoduledefs.py. This change avoids the build exploding, since the new regex matches the last two args as a single argument and generates a malformed module defs include. The pattern here exploits the fact that 1.18 and below do not preprocess files, so both MP_REGISTER_MODULE lines are included in the source, but only the three arg version is matched by regex. In >1.18 the files will be processed and the three arg version removed before makemoduledefs.py processes it.		2022-06-14 12:08:47 +01:00
..
README.md	Add SCD41 MicroPython bindings	2021-12-16 11:39:34 +00:00
breakout_scd41.c	MicroPython: Shim MP_REGISTER_MODULE for >1.18 compat.	2022-06-14 12:08:47 +01:00
breakout_scd41.cpp	MicroPython: Promote machine.I2C() to PimoroniI2C.	2022-05-18 13:20:33 +01:00
breakout_scd41.h	Add SCD41 MicroPython bindings	2021-12-16 11:39:34 +00:00
micropython.cmake	Add SCD41 MicroPython bindings	2021-12-16 11:39:34 +00:00

README.md

SCD41 CO2 Sensor Driver

Getting Started

Construct a new PimoroniI2C instance for your specific board. Breakout Garden uses pins 4 & 5 and Pico Explorer uses pins 20 & 21.

Since SCD41 has a fixed I2C address and the Sensirion SCD4x library is used under the hood, it's wrapped up as a module for Python.

Import the breakout_scd41 and call init to set up I2C:

import time

import pimoroni_i2c
import breakout_scd41

i2c = pimoroni_i2c.PimoroniI2C(4, 5)

breakout_scd41.init(i2c)

Taking Measurements

Before taking a measurement you must start periodic measurement by calling start().

Poll on ready() and use measure() to read the result when it's True:

breakout_scd41.start()

while True:
    if breakout_scd41.ready():
        co2, temperature, humidity = breakout_scd41.measure()
        print(co2, temperature, humidity)
        time.sleep(1.0)

The measure() method will return a Tuple containing the CO2 reading, temperature in degrees C and humidity.