#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>

#define SCREEN_WIDTH 128 // OLED display width, in pixels
#define SCREEN_HEIGHT 64 // OLED display height, in pixels

#define trigPin 5
#define echoPin 18
#define SOUND_SPEED 0.034
#define CM_TO_INCH 0.393701

Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, -1);

void setup() {
  Serial.begin(115200);
  pinMode(trigPin, OUTPUT); // Set trigPin as an output

  if(!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)) {
    Serial.println(F("SSD1306 allocation failed"));
    for(;;);
  }

  display.clearDisplay();
  display.setTextSize(1);
  display.setTextColor(SSD1306_WHITE);
}

void loop() {
  digitalWrite(trigPin, LOW);
  delayMicroseconds(1);
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);

  long duration = pulseIn(echoPin, HIGH);
  float distanceCm = duration * SOUND_SPEED / 2;
  float distanceInch = distanceCm * CM_TO_INCH;

  display.clearDisplay();
  display.setCursor(0, 0);
  display.println("Distance (cm): ");
  display.println(distanceCm);
  display.println("Distance (inch): ");
  display.println(distanceInch);
  display.display();

  Serial.print("Distance (cm): ");
  Serial.println(distanceCm);
  Serial.print("Distance (inch): ");
  Serial.println(distanceInch);

  delay(1000);
}