#include "U8glib.h" 
 
U8GLIB_SSD1306_128X64 u8g; // create an instant of OLED display 
 
void setup() { 
  u8g.setFont(u8g_font_7x13); // set the font for text 
  //u8g.setColorIndex(1); set the display colour can be done outside picture loop 
} 
 
void loop() { 
  u8g.firstPage(); //marks the beginning of the picture loop. 
  do { 
    u8g.setColorIndex(1); // set the colour to white 
 
    u8g.drawCircle(64,20,10); // draw circle with centre at (64,20) and radius = 10
 
    u8g.setColorIndex(0); //change the colour back to black

    u8g.setColorIndex(1); // set the colour to white 
 
    u8g.drawCircle(32,20,10); // draw circle with centre at (32,20) and radius = 10 
 
    u8g.setColorIndex(0); //change the colour back to black

    u8g.setColorIndex(1); // set the colour to white 
 
    u8g.drawCircle(48,40,10); // draw circle with centre at (48,40) and radius = 10 
 
    u8g.setColorIndex(0); //change the colour back to black 

    u8g.setColorIndex(1); // set the colour to white 
 
    u8g.drawCircle(80,40,10); // draw circle with centre at (80,40) and radius = 10 
 
    u8g.setColorIndex(0); //change the colour back to black 

    u8g.setColorIndex(1); // set the colour to white 
 
    u8g.drawCircle(96,20,10); // draw circle with centre at (96,20) and radius = 10 
 
    u8g.setColorIndex(0); //change the colour back to black 
     
  } while ( u8g.nextPage() ); //marks the end of the body of the picture loop 
 
  u8g.setColorIndex(1); 
  u8g.drawStr(0, 20, "outside");  
  //drawing function must use inside the picture loop. 
}