from machine import Pin, ADC, Timer
from neopixel import NeoPixel
from time import sleep

# set all colours to zero initially
red = 0
green = 0
blue = 0

ring = NeoPixel(Pin(12), 16)  # initialize 16-element NeoPixel Ring on GPIO pin 12

pot1 = ADC(Pin(36)) # pin 36 will be used as an ADC input line
pot2 = ADC(Pin(39)) # pin 39 will be used as an ADC input line
pot3 = ADC(Pin(34)) # pin 34 will be used as an ADC input line

switch = Pin(19,Pin.IN,Pin.PULL_UP)

def my_timer_ISR (timer): # internal interrupt service routine (ISR)
    global red,green,blue
    red = int(pot1.read()/16)
    green = int(pot2.read()/16)
    blue = int(pot3.read()/16)

my_timer = Timer(0)

my_timer.init(mode = Timer.PERIODIC, period = 100, callback = my_timer_ISR )



while True:

    direction = switch.value()  # inspect switch position
    
    if direction == 0: # clockwise rotation
        for i in range(16):
            ring[i] = (red, green, blue)     
            ring.write()
            sleep(0.25)

    else: # anti-clockwise rotation
        for i in range(15,-1,-1):
            ring[i] = (red, green, blue)      
            ring.write()
            sleep(0.25)