[SOLVED] GPIO pin cleanup

GPIO pin cleanup

I have used python for a while now, however, I am new to using a Raspberry Pi and things such as GPIO pins. I recently bought a Freenove Ultrasonic starter kit to help me learn. They have a tutorial included that I am following. In the program I keep getting this error message:

lgpio.error 'gpio busy'

I have tried loads of things. I know it could be a few things: In a previous project I didn't cleanup the GPIO pins properly or I exported the pins and didn't reverse it.

I have tried numerous commands and script to cleanup the code but it wont work. I also rebooted the Raspberry Pi5 a few times. Here is the code I used for my project:

from gpiozero import LED, Button
import time


led = LED(17)  # define LED pin according to BCM Numbering
button = Button(18)  # define Button pin according to BCM Numbering


def onButtonPressed():
    # When button is pressed, this function will be executed
    led.toggle()

    if led.is_lit:
        print("Led turned on >>>")
    else:
        print("Led turned off <<<")


def loop():
    # Button detect
    button.when_pressed = onButtonPressed
    while True:
        time.sleep(1)


def destroy():
    led.close()
    button.close()


if __name__ == '__main__':
    # Program entrance

    print('Program is starting...')
    try:
        loop()

    except KeyboardInterrupt:
        # Press ctrl-c to end the program.
        destroy()
        print("Ending program")

Solution

The Error is in your "loop" function. First of all you are assigning your "onButtonPressed" function to the class function "when_pressed" of Button, which you have assigned your button variable to. Then you put "sleep(1)" in a loop which pauses the main thread you are trying to execute your program on.

The correct approach to listening to your button input would be something like this:

def loop():
    while True:
        if(button.when_pressed):
            onButtonPressed()
            time.sleep(1)

Note: because of missing context here I am assuming that "button.when_pressed" returns something like "True" or "False".