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

const int adc = 36;
int current = 0;
int previous = 0; 
int check = 0;
#define SCREEN_WIDTH 128
#define SCREEN_HEIGHT 64

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

void setup() {
  Serial.begin(115200);

  if(!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)) { // Address 0x3D for 128x64
    Serial.println(F("SSD1306 allocation failed"));
    for(;;);
  }
  delay(2000);
  display.clearDisplay();
}

void loop() {
  if(check < SCREEN_WIDTH){
    check = check + 1;
    previous = current; 
    current = round(analogRead(adc) * SCREEN_HEIGHT / 4096);
    display.drawLine(check - 1, SCREEN_HEIGHT - previous, check, SCREEN_HEIGHT - current, WHITE);
    display.display();
    
  } else {
    check = 0;
    current = 0;
    display.clearDisplay();
  }

}