Simple test

Ensure your device works with this simple test.

examples/scd30_simpletest.py

# SPDX-FileCopyrightText: 2020 by Bryan Siepert, written for Adafruit Industries
#
# SPDX-License-Identifier: Unlicense
import time

import board
import busio

import adafruit_scd30

# SCD-30 has tempremental I2C with clock stretching, datasheet recommends
# starting at 50KHz
i2c = busio.I2C(board.SCL, board.SDA, frequency=50000)
scd = adafruit_scd30.SCD30(i2c)

while True:
    # since the measurement interval is long (2+ seconds) we check for new data before reading
    # the values, to ensure current readings.
    if scd.data_available:
        print("Data Available!")
        print(f"CO2: {scd.CO2:d} PPM")
        print(f"Temperature: {scd.temperature:0.2f} degrees C")
        print(f"Humidity: {scd.relative_humidity:0.2f} % rH")
        print("")
        print("Waiting for new data...")
        print("")

    time.sleep(0.5)

Tuning Knobs

Experiment with different tuning parameters and settings

examples/scd30_tuning_knobs.py

# SPDX-FileCopyrightText: 2020 by Bryan Siepert, written for Adafruit Industries
#
# SPDX-License-Identifier: Unlicense
import time

import board
import busio

import adafruit_scd30

# SCD-30 has tempremental I2C with clock stretching, datasheet recommends
# starting at 50KHz
i2c = busio.I2C(board.SCL, board.SDA, frequency=50000)
scd = adafruit_scd30.SCD30(i2c)
# scd.temperature_offset = 10
print("Temperature offset:", scd.temperature_offset)

# scd.measurement_interval = 4
print("Measurement interval:", scd.measurement_interval)

# scd.self_calibration_enabled = True
print("Self-calibration enabled:", scd.self_calibration_enabled)

# scd.ambient_pressure = 1100
print("Ambient Pressure:", scd.ambient_pressure)

# scd.altitude = 100
print("Altitude:", scd.altitude, "meters above sea level")

# scd.forced_recalibration_reference = 409
print("Forced recalibration reference:", scd.forced_recalibration_reference)
print("")

while True:
    data = scd.data_available
    if data:
        print("Data Available!")
        print("CO2:", scd.CO2, "PPM")
        print("Temperature:", scd.temperature, "degrees C")
        print("Humidity::", scd.relative_humidity, "%%rH")
        print("")
        print("Waiting for new data...")
        print("")

    time.sleep(0.5)

MCP2221 and SCD30 Example

MCP2221 is known to not like the SCD30. Here is how to avoid this!

examples/scd30_tuning_knobs.py

# SPDX-FileCopyrightText: 2020 by Bryan Siepert, written for Adafruit Industries
#
# SPDX-License-Identifier: Unlicense
import time

import board
import busio

import adafruit_scd30

# SCD-30 has tempremental I2C with clock stretching, datasheet recommends
# starting at 50KHz
i2c = busio.I2C(board.SCL, board.SDA, frequency=50000)
scd = adafruit_scd30.SCD30(i2c)
# scd.temperature_offset = 10
print("Temperature offset:", scd.temperature_offset)

# scd.measurement_interval = 4
print("Measurement interval:", scd.measurement_interval)

# scd.self_calibration_enabled = True
print("Self-calibration enabled:", scd.self_calibration_enabled)

# scd.ambient_pressure = 1100
print("Ambient Pressure:", scd.ambient_pressure)

# scd.altitude = 100
print("Altitude:", scd.altitude, "meters above sea level")

# scd.forced_recalibration_reference = 409
print("Forced recalibration reference:", scd.forced_recalibration_reference)
print("")

while True:
    data = scd.data_available
    if data:
        print("Data Available!")
        print("CO2:", scd.CO2, "PPM")
        print("Temperature:", scd.temperature, "degrees C")
        print("Humidity::", scd.relative_humidity, "%%rH")
        print("")
        print("Waiting for new data...")
        print("")

    time.sleep(0.5)