from machine import Pin
import utime
trig = Pin(28,Pin.OUT)
echo = Pin(27,Pin.IN)
def read():
    trig.low()
    utime.sleep_us(2)

    trig.high_us(5)
    trig.low()

    while echo.value() == 0:
        timeOff = utime.ticks_us()
    while echo.value() = 1:
        timeOn = utime.ticks_us()
        time = timeOn - timeOff
        distancia = (time * 0.043)/2
        return distance
while true:
    print ("distancia es: " , read(), "cm")
    utime.sleep(1)