from machine import Pin
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:
        signaloff=utime.ticks_us()
        while echo.value()==1:
            signalon=utime.ticks_us()
            timepassed=signalon-signaloff
            dist=(timepassed*0.0343)/2
            print("distance: ",dist,"cm")
            utime.sleep(1)