How to Control an LED

The LED class in the RpiL library provides basic control for an LED connected to a Raspberry Pi GPIO pin. This class allows turning the LED on and off, toggling its state, and blinking it with a specified duration.

The LED class accepts one argument:

  • Pin Number

    • The Broadcom GPIO pin number connected to the LED.

Here is an example of using the LED class:

from RpiL import LED
import time

led = LED(18)  # Create an LED instance on GPIO pin 18

led.on()       # Turn the LED on
time.sleep(2)  # Wait for 2 seconds
led.off()      # Turn the LED off
time.sleep(1)  # Wait for 1 second
led.blink(10)  # Blink the LED for 10 seconds

This example sets up an LED on GPIO pin 18, turns it on, turns it off, and then blinks it for 10 seconds.

Methods

  • on()

    • Turns the LED on.

  • off()

    • Turns the LED off.

  • toggle()

    • Toggles the LED’s state. If it is on, it turns off; if it is off, it turns on.

  • blink(duration=6)

    • Blinks the LED in a non-blocking manner for the specified duration (default is 6 seconds). This method uses a separate thread to allow other code to run while the LED blinks.

  • blink_sequence(duration=6)

    • The internal method responsible for blinking the LED by turning it on and off in half-second intervals.

Notes

  • The blink method initiates a separate thread for non-blocking operation, allowing the LED to blink while other processes continue.

  • The __del__ method ensures that the LED is turned off and the GPIO pin is cleaned up when the LED instance is deleted.

Cleanup

The class destructor (__del__) turns the LED off, waits for any active blink thread to finish, and cleans up the GPIO pin.