80 lines
1.8 KiB
Python
80 lines
1.8 KiB
Python
# SPDX-FileCopyrightText: 2018 Mikey Sklar for Adafruit Industries
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#
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# SPDX-License-Identifier: MIT
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import time
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import adafruit_sgp30
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import board
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import busio
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i2c = busio.I2C(board.SCL, board.SDA, frequency=100000)
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# Create library object on our I2C port
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sgp30 = adafruit_sgp30.Adafruit_SGP30(i2c)
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sgp30.iaq_init()
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sgp30.set_iaq_baseline(0x8973, 0x8aae)
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# highest tVOC recorded in 30 seconds
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highest_breath_result = 0
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def warmup_message():
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warmup_time = 20
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warmup_counter = 0
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# initial read required to get sensor going
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sgp30.iaq_measure()
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print()
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print("Warming Up [%d seconds]..." % warmup_time)
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while warmup_counter <= 20:
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print('.', end='')
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time.sleep(1)
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warmup_counter += 1
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def get_breath_reading():
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breath_time = 30 # seconds to record breath reading
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# one second count up to breath_time value
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breath_counter = 0
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# initialize list with empty values
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breath_saves = [0] * (breath_time + 1)
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print()
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print("We will collect breath samples for 30 seconds.")
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print("Take a deep breath and exhale into the straw.")
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input(" *** Press a key when ready. *** ")
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print()
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while breath_counter <= breath_time:
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_, tvoc = sgp30.iaq_measure()
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breath_saves[breath_counter] = tvoc
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print(tvoc, ', ', end='')
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time.sleep(1)
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breath_counter += 1
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breath_saves = sorted(breath_saves)
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result = breath_saves[breath_counter - 1]
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return result
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# show the highest reading recorded
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def show_results(breath_result):
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print()
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print()
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print("peak VOC reading:", breath_result)
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print()
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input("Press any key to test again")
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print()
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# main
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while True:
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warmup_message()
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highest_breath_result = get_breath_reading()
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show_results(highest_breath_result)
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