import machine
import time

segment_pins = [machine.Pin(i, machine.Pin.OUT) for i in range(2, 9)]
dp_pin = machine.Pin(16, machine.Pin.OUT)
digit_pins = [machine.Pin(i, machine.Pin.OUT) for i in range(9, 13)]
adc = machine.ADC(26)

segment_digits = {
    '0': [1, 1, 1, 1, 1, 1, 0],
    '1': [0, 1, 1, 0, 0, 0, 0],
    '2': [1, 1, 0, 1, 1, 0, 1],
    '3': [1, 1, 1, 1, 0, 0, 1],
    '4': [0, 1, 1, 0, 0, 1, 1],
    '5': [1, 0, 1, 1, 0, 1, 1],
    '6': [1, 0, 1, 1, 1, 1, 1],
    '7': [1, 1, 1, 0, 0, 0, 0],
    '8': [1, 1, 1, 1, 1, 1, 1],
    '9': [1, 1, 1, 1, 0, 1, 1],
    ' ': [0, 0, 0, 0, 0, 0, 0],
}

display_value = "0000"
current_digit = 0

def read_voltage_mv():
    raw = adc.read_u16()
    return int((raw / 65535) * 3300)

def update_display(timer):
    global current_digit, display_value

    for pin in digit_pins:
        pin.value(0)

    char = display_value[current_digit] if current_digit < len(display_value) else ' '
    segments = segment_digits.get(char, segment_digits[' '])

    for i in range(7):
        segment_pins[i].value(1 - segments[i])

    dp_pin.value(1 if current_digit == 0 else 0)
    digit_pins[current_digit].value(1)
    current_digit = (current_digit + 1) % 4

def update_sensor(timer):
    global display_value
    voltage = read_voltage_mv()
    display_value = f"{voltage:04}"[-4:]
    print("Voltage (mV):", voltage)

def setup():
    for pin in segment_pins + digit_pins:
        pin.value(0)
    dp_pin.value(0)

    display_timer = machine.Timer()
    display_timer.init(freq=1000, mode=machine.Timer.PERIODIC, callback=update_display)

    sensor_timer = machine.Timer()
    sensor_timer.init(period=2000, mode=machine.Timer.PERIODIC, callback=update_sensor)

setup()