nespi npn fan

fan.py

import RPi.GPIO as IO
from gpiozero import CPUTemperature
import time

import logging

minspin = 25

logger = logging.getLogger(__name__)

def main():

    IO.setwarnings(False)
    IO.setmode(IO.BCM)
    IO.setup(21,IO.OUT)
    fan = IO.PWM(21, 100)

    cpu = CPUTemperature()
    fan.start(0)

    oldtemp = 0

    while True:
        temp = cpu.temperature
        if abs(temp - oldtemp) < 1.5:

            time.sleep(2)
            continue

        oldtemp = temp
        if temp > 50:
            speed = max(5, min(100, ((temp - 45)*4)+minspin))

            fan.ChangeDutyCycle(speed)
            logger.info(f"Temperature changed to: {temp}. Adjusting fan speed to {speed}")
        else:

            fan.ChangeDutyCycle(0)
            logger.info("Turning fan off")
        time.sleep(1)

    fan.stop()
    IO.cleanup()

    logger.info("Exiting mainloop...")

if __name__ == "__main__":
    logging.basicConfig(level=logging.INFO)
    main()