from machine import Pin,PWM
import time
from time import sleep_us, sleep, ticks_us
trig =Pin(23,Pin.OUT)
echo =Pin(22,Pin.IN)
while True:
    distance=0
    trig.value(1)
    sleep_us(10)
    trig.value(0)
    while echo.value()==0:
        pass
    if echo.value()==1:
        ts=ticks_us()
        while echo.value()==1:
            pass
        te=ticks_us()
        tc=te-ts
        distance=(tc*170)/10000
    print(distance,'cm')
    sleep(1)
    if 0<distance<100:
        beep = PWM(Pin(2), freq = 776, duty = 128)
        time.sleep(0.005)
        beep.deinit()
        time.sleep(0.005)
    if 100<distance<200:
        beep = PWM(Pin(2), freq = 660, duty = 128)
        time.sleep(0.025)
        beep.deinit()
        time.sleep(0.025)
    if 200<distance<300:
        beep = PWM(Pin(2), freq = 560, duty = 128)
        time.sleep(0.075)
        beep.deinit()
        time.sleep(0.075)
    if 300<distance<400:
        beep = PWM(Pin(2), freq = 441, duty = 128)
        time.sleep(0.1)
        beep.deinit()
        time.sleep(0.1)