#include <SPI.h>
#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>
#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)){
    Serial.println(F("Failed to start SSD1306 OLED display!"));
    while(1);
  }
  delay(2000);
  display.setCursor(0,0);
}

void loop() {
  display.clearDisplay();
  display.drawCircle(64,32,30,WHITE);
  display.display();
  delay(1000);

  display.clearDisplay();
  display.fillCircle(64,32,30,WHITE);
  display.display();
  delay(1000);
}