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Fan does not start on RPi bootup
Hi, I am having trouble trying to get the PWM fan to spin on bootup. Whenever my Pi reboots I always have to run the fan-rpi.py file in order for the fan to start spinning again. I modified the file to my preferences but am not too experienced with Pi GPIO & the fan settings to debug what went wrong. The file works properly but I can't seem to get the file to run at startup. Here's what I have:
#!/usr/bin/python3
# DON'T use pigpiod library on Nov. 24 2022 by Harry Huang
#import pigpio
import RPi.GPIO as IO
import time
import subprocess
servo = 18
IO.setwarnings(False)
IO.setmode (IO.BCM)
IO.setup(servo,IO.OUT)
fan = IO.PWM(servo,2000)
fan.start(0)
def get_temp():
output = subprocess.run(['vcgencmd', 'measure_temp'], capture_output=True)
temp_str = output.stdout.decode()
try:
return float(temp_str.split('=')[1].split('\'')[0])
except (IndexError, ValueError):
raise RuntimeError('Could not get temperature')
while 1:
temp = get_temp() # Get the current CPU temperature
if temp > 60: # Check temperature threshhold, in degrees celcius
fan.ChangeDutyCycle(100) # Set fan duty based on temperature, 100 is max speed and 0 is min speed or off.
elif temp > 50:
fan.ChangeDutyCycle(90)
elif temp > 40:
fan.ChangeDutyCycle(60)
elif temp > 30:
fan.ChangeDutyCycle(30)
else:
fan.ChangeDutyCycle(20)
time.sleep(5) # Sleep for 5 seconds
I also was wondering if it's possible to use this Noctua fan (https://www.amazon.com/gp/product/B00NEMGCIA/ref=ox_sc_act_title_1?smid=A1Z5H6ZGWCMTNX&psc=1), and it would run DC 5V correct? No PWM, so no fan control?
Hello, Here is my modified fan.py and running the python script in systemd daemon. I also created ansible tasks pigpio.yml which automates the installation of pigpio and fan.py installation
