from lcd_hd44780 import LcdHd44780
from machine import Timer

def stopwatch_100ms(t):
    """Interrupt handler of Timer executed every 100 millisecs"""
    global tenths, seconds, minutes  # Can update global variable here

    tenths += 1# Modify tenths of seconds

    tenths_str = str(tenths)
    seconds_str = str(seconds)
    minutes_str = str(minutes)

    # Display tenths of seconds
    lcd.move_to(2,3)
    if minutes <= 9:
        lcd.write("0")
    lcd.write(minutes_str + ":")
    if seconds <= 9:
        lcd.write("0")
    lcd.write(seconds_str+"."+tenths_str)

lcd = LcdHd44780(rs=26, e=25, d=[13, 12, 23, 27])

# Default screen
lcd.move_to(1,1)
lcd.write("Stopwatch:")

tim = Timer(0)
tim.init(period=100, 
         mode=Timer.PERIODIC,
         callback=stopwatch_100ms)

tenths = 0
seconds = 0
minutes = 0 

print("Start counting. Press `Ctrl+C` to stop")

try:
    while True:
        if tenths > 9:
            seconds += 1
            tenths = 0
        if seconds > 59:
            minutes += 1
            seconds = 0

except KeyboardInterrupt:
    print("Program stopped. Exiting...")
    lcd.command(0x01)  
    tim.deinit()