from hcsr04 import HCSR04
from machine import Timer
from time import sleep
sensor = HCSR04(trigger_pin=5, echo_pin=18, echo_timeout_us=10000)
tim0 = Timer(0)
ON =1
OFF =0
led1 = Pin(13,Pin.OUT);led2 = Pin(12,Pin.OUT)
def mycallback1(timer):
 global distance
 distance = sensor.distance_cm()
 print(" Distance=",distance)
while True:
 led1.value(ON)
 sleep(1)
 led1.value(OFF)
 sleep(1)