Troubleshooting • RPI 4 B GPIO not working WHEN connecting Printers

Code:

import RPi.GPIO as GPIOimport time# GPIO pin connected to the COIN pin of the coin selectorCOIN_PIN = 24# Setup GPIOGPIO.setmode(GPIO.BCM)GPIO.setup(COIN_PIN, GPIO.IN, pull_up_down=GPIO.PUD_DOWN)SET_PIN = 18GPIO.setup(SET_PIN, GPIO.OUT)# Variable to track pulse count and time of the last pulsepulse_count = 0last_pulse_time = time.time()  # Initialize last pulse time# Threshold for detecting no more pulses (in seconds)NO_PULSE_THRESHOLD = 1  # 1 second# Minimum time between valid pulses (debounce duration in seconds)DEBOUNCE_TIME = 0.02  # 20 milliseconds# Timestamp of the last valid pulselast_valid_pulse = 0#GPIO.output(SET_PIN, GPIO.HIGH)# Callback function to detect coin insertiondef coin_detected(channel):    global pulse_count, last_pulse_time, last_valid_pulse    current_time = time.time()    GPIO.output(SET_PIN, GPIO.LOW)    print("counting")    # Debounce logic: Ignore pulses too close to each other    if current_time - last_valid_pulse > DEBOUNCE_TIME:        pulse_count += 1        last_pulse_time = current_time  # Update time of the last pulse        last_valid_pulse = current_time# Detect coin insertion (using rising edge detection)GPIO.add_event_detect(COIN_PIN, GPIO.RISING, callback=coin_detected, bouncetime=10)print("Waiting for pulses... Press Ctrl+C to exit.")try:    while True:        current_time = time.time()        # Check if no pulses have been detected for the threshold duration        if pulse_count > 0 and current_time - last_pulse_time > NO_PULSE_THRESHOLD:            print(f"Final pulse count: {pulse_count}")            GPIO.output(SET_PIN, GPIO.HIGH)            print("No more pulses detected.")            pulse_count = 0  # Reset pulse count for the next cycle        time.sleep(0.1)  # Small delay to prevent high CPU usage        #GPIO.output(SET_PIN, GPIO.HIGH)except KeyboardInterrupt:    print("\nExiting...")    GPIO.cleanup()