from machine import *
from hcsr04 import *
from time import sleep
PWM_servo = PWM(Pin(17),freq=50,duty=0)
sensor = HCSR04(trigger_pin=15, echo_pin=2,echo_timeout_us=1000000)

def Servo(servo,angle):
    PWM_servo.duty(int(((angle)/180*2+0.5)/20*1023))

while True:
    distance = round(sensor.distance_cm(),2) 
    #tran_dis = '%.2f' %(distance)
    print("distance :", distance," cm")
    if distance <= 150:
        Servo(17,0)  
    else:
        Servo(17,90)
    sleep(1)