# Read A/D channel 2 every 1.00ms

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

a2d2 = machine.ADC(2)
tim = Timer()

flag = 0
k = 3.3 / 65520
dT = 0.001

def tick(timer):
    global flag
    flag = 1
        
tim.init(freq=1000, mode=Timer.PERIODIC, callback=tick)

LED = Pin(16,Pin.OUT)

while(1):
    LED.value(0)
    while(flag == 0):
        pass
    LED.value(1)
    flag = 0

    a2 = a2d2.read_u16()
    V2 = k*a2
    
    print('{: 7.4f}'.format(V2))