Library for OLED-displays runs on AVR
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OLED for AVR mikrocontrollers

Library for oled-displays with SSD1306 or SH1106 display-controller connected with I2C at an AVR Atmel Atmega like Atmega328P.

This library allows you to display text or/and graphic at oled-display. The library need less than 2 kilobytes flash-memory and 3 bytes sram in textmode, in graphicmode library need less than 3 kilobytes flash-memory and 1027 bytes static sram so you can use oled-displays e.g with Atmega48PA (only with textmode). Library is only tested with 128x64 Pixel display, lower resolution not tested but should work too.

If you want to use your own I2C library you have to fit i2c-function at lcd-library. Settings for I2C-bus have to set at i2c.h Settings for display have to set at lcd.h

If you want to use characters like e.g. ä set your compiler input-charset to utf-8 and your compiler exec-charset to iso-8859-15 (look at makefile line 115).

Testcondition: Display: SSD1306 OLED, Compiler Optimizelevel: -Os, µC: Atmega328p @ 8 MHz internal RC


Modul Flash Static RAM
I2C-Core 120 Bytes 0 Bytes
FONT 644 Bytes 0 Bytes
OLED (Text-Mode) 1475 Bytes 3 Bytes
OLED (Graphic-Mode) 2473 Bytes 1027 Bytes

Speed (print 20 charaters (1 line) in normal size to display):

Mode Time I2C-Speed RAM
OLED (Text-Mode) 4.411 ms 400 kHz
OLED (Text-Mode) 15.384 ms 100 kHz
OLED (Graphic-Mode) 26.603 ms 400 kHz
OLED (Graphic-Mode) 96.294 ms 100 kHz


#include "lcd.h"

int main(void){
  lcd_init(LCD_DISP_ON);    // init lcd and turn on
  lcd_puts("Hello World");  // put string from RAM to display (TEXTMODE) or buffer (GRAPHICMODE)
  lcd_gotoxy(0,2);          // set cursor to first column at line 3
  lcd_puts_p(PSTR("String from flash"));  // puts string form flash to display (TEXTMODE) or buffer (GRAPHICMODE)
#if defined GRAPHICMODE
  lcd_drawCircle(64,32,7,WHITE); // draw circle to buffer
  lcd_display();                  // send buffer to display
    //main loop
  return 0;

example for chars with double height:

#include "lcd.h"

int main(void){
    lcd_puts("Normal Size");
    lcd_puts("  Double  \r\n   Size");
    //main loop
    return 0;