import utime
trigger=Pin(15,Pin.OUT)
echo=Pin(14,Pin.IN)
while true:
    trigger.low()
    utime.sleep_us(2)
    trigger.high()
    utime.sleep_us(5)
    trigger.low()
    while echo.value()==0:
        signal off=utime.ticks us()
    while echo.value()==1:
        signal on=utime.ticks_us()
    time Passed=signal on-signal off
        distance=(time passed*0.0343)/2
    print("total distance",distance,"cm")
    print("sensor")
    utime.sleep(1)