40 lines
1.0 KiB
Markdown
40 lines
1.0 KiB
Markdown
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# SCD41 CO2 Sensor Driver <!-- omit in toc -->
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## Getting Started
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Construct a new PimoroniI2C instance for your specific board. Breakout Garden uses pins 4 & 5 and Pico Explorer uses pins 20 & 21.
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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.
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Import the `breakout_scd41` and call `init` to set up I2C:
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```python
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import time
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import pimoroni_i2c
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import breakout_scd41
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i2c = pimoroni_i2c.PimoroniI2C(4, 5)
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breakout_scd41.init(i2c)
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```
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## Taking Measurements
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Before taking a measurement you must start periodic measurement by calling `start()`.
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Poll on `ready()` and use `measure()` to read the result when it's `True`:
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```python
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breakout_scd41.start()
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while True:
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if breakout_scd41.ready():
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co2, temperature, humidity = breakout_scd41.measure()
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print(co2, temperature, humidity)
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time.sleep(1.0)
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```
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The `measure()` method will return a Tuple containing the CO2 reading, temperature in degrees C and humidity.
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