from time import sleep
from machine import Pin
from machine import PWM

# ====================
#   Set up LED pin
# ====================
# Pin setup for 
led = PWM(Pin(0))
led.freq(1000)

# Note: We can easily set how fast the led goes 
# from MIN to MAX by setting an increment
MIN_LIGHT   = 0
MAX_LIGHT   = 65025
INC_LIGHT   = 5000


# This function just sets the current brightness of the led
# and pauses for .25 seconds
def setLedCycle(brightness):
    led.duty_u16(brightness)
    print(f"Brightness: {brightness}")
    sleep(.25)

while True:
     # Incrementally brighten the light by INC_LIGHT from MIN_LIGHT to MAX_LIGHT
    for brightness in range(MIN_LIGHT, MAX_LIGHT, INC_LIGHT):
        setLedCycle(brightness)
        print(f"Brightness +: {brightness}")

    # We darken the light by INC_LIGHT from MAX_LIGHT to MIN_LIGHT
    for brightness in range(MAX_LIGHT, MIN_LIGHT , -INC_LIGHT):
        setLedCycle(brightness)
        print(f"Brightness -: {brightness}")

print("Starting up")