from machine import Pin, I2C
from ssd1306 import SSD1306_I2C
import utime

trigger = Pin(3, Pin.OUT)
echo = Pin(2, Pin.IN)

def ultrasonic():
    timepassed = 0
    trigger.low()
    utime.sleep_us(2)
    trigger.high()
    utime.sleep_us(10)
    trigger.low()
    
    while echo.value() == 0:
        signaloff = utime.ticks_us()
    while echo.value() == 1:
        signalon = utime.ticks_us()
    timepassed = signalon - signaloff
    
    return timepassed

WIDTH  = 128  # OLED display width
HEIGHT = 64   # OLED display height

i2c = I2C(0, scl=Pin(1), sda=Pin(0), freq=200000)  # Init I2C using pins GP0 & GP1
print("I2C Address      : "+hex(i2c.scan()[0]).upper())  # Display device address
print("I2C Configuration: "+str(i2c))                    # Display I2C config

oled = SSD1306_I2C(WIDTH, HEIGHT, i2c)  # Init OLED display

while True:
    oled.fill(0)
    measured_time = ultrasonic()  # Measure time
    distance_cm = (measured_time * 0.0343) / 2  # Convert time to distance
    distance_cm = round(distance_cm, 2)

    oled.text("Distance", 20, 15)
    oled.text(str(distance_cm) + " cm", 20, 35)
    oled.show()
    utime.sleep(1)