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

#define screenWidth 128
#define screenHeight 64

Adafruit_SSD1306 display(screenWidth, screenHeight, &Wire, -1);

void setup() {
  // put your setup code here, to run once:
  Serial.begin(115200);
  if (!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)){
    Serial.println("FAILED TO CONNECT!");
    while (1);
  }
  delay(1000);
  display.setCursor(0, 0);
}

void loop() {
  display.clearDisplay();
  display.drawRect(40, 20, 60, 40, WHITE);
  display.display();
  delay(1000);
  
  display.clearDisplay();
  display.fillRect(40, 20, 60, 40, WHITE);
  display.display();
  delay(1000);
}