examples/rp2/pwm_fade.py


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# Example using PWM to fade an LED.
# Note: this does not work on Pico W because it uses Pin(25) for LED output.

# ruff: noqa: F821 - @asm_pio decorator adds names to function scope

import time
from machine import Pin, PWM


# Construct PWM object, with LED on Pin(25).
pwm = PWM(Pin(25))

# Set the PWM frequency.
pwm.freq(1000)

# Fade the LED in and out a few times.
duty = 0
direction = 1
for _ in range(8 * 256):
    duty += direction
    if duty > 255:
        duty = 255
        direction = -1
    elif duty < 0:
        duty = 0
        direction = 1
    pwm.duty_u16(duty * duty)
    time.sleep(0.001)