from machine import Pin
import time

# Sonar
class Sonar:
    def __init__(self, trig, echo):
        self.trig=Pin(trig, Pin.OUT)
        self.echo=Pin(echo, Pin.IN)

    def checkdist(self):
        #trig, echo = Pin(trig, Pin.OUT), Pin(echo, Pin.IN)
        self.trig.value(0)
        self.echo.value(0)
        self.trig.value(1)
        time.sleep_us(10)
        self.trig.value(0)
        while(self.echo.value()==0):
            pass
        t1 = time.ticks_us()
        while(self.echo.value()==1):
            pass
        t2 = time.ticks_us()
        return round(time.ticks_diff(t2, t1) / 10000 * 340 / 2, 2)