from utime import sleep
from machine import Pin, PWM
from random import getrandbits

# functions to convert duty cycle between percentage & int16
def dutytoPercent(duty16):
    return 100 * duty16 / (2**16-1)
def dutyfromPercent(duty):
    return int((2**16-1)*duty/100)

# create array of pin numbers for RGB LED
pins = [9, 8, 7]
# create array of duty cycle in percent
duty = [50, 50, 50]
# Create array of PWM pins with freq of 50Hz and duty of 50%
leds = [
    PWM(Pin(pins[0]), freq=50, duty_u16=dutyfromPercent(duty[0])), 
    PWM(Pin(pins[1]), freq=50, duty_u16=dutyfromPercent(duty[1])),
    PWM(Pin(pins[2]), freq=50, duty_u16=dutyfromPercent(duty[2]))
    ]
print(f"Red duty: {duty[0]:.1f}%, Green duty: {duty[1]:.1f}%, Blue duty: {duty[2]:.1f}%")
sleep(0.1) # Wait for USB to become ready
# loop for random colours
while True:
    try:
        for led in range(3):
            # get a new random 16 bit number for duty cycle
            leds[led].duty_u16(getrandbits(16))
            duty[led] = dutytoPercent(leds[led].duty_u16())
        print(f"Red duty: {duty[0]:.1f}%, Green duty: {duty[1]:.1f}%, Blue duty: {duty[2]:.1f}%")
        sleep(2)
    except KeyboardInterrupt:
        break
# disable PWM output and turn off LEDs
for led in range(3):
    leds[led].deinit()
    Pin(pins[led], Pin.OUT, value=0)
print("Finished.")