SSD1306_OLED_HW_I2C

A minimalistic adaptation of Neven Boyanov’s SSD1306 library (http://tinusaur.org) for ATmega328P-based boards

Description

This library is designed to control a 128x64 OLED display with an SSD1306 controller over I2C. In essence, it is a minimalistic adaptation of a library written for ATTiny85 and similar micro-controllers by Neven Boyanov (http://tinusaur.org). The purpose of this adaptation is to reduce the memory footprint, and add hardware support for I2C communication on ATmega328P-based boards. The library can be used with Arduino IDE or in a plain C environment. I have tested it on a Chinese "Arduino Nano" clone and on a bare ATmega328P chip (running with an internal 8 MHz oscillator).

Installation

git clone https://github.com/ex-punctis/SSD1306_OLED_HW_I2C or download the repository as a zip file.

Arduino IDE

Create a folder for your project and move SSD1306_OLED_HW_I2C.c, SSD1306_OLED_HW_I2C.h and demo.ino to your folder. Rename demo.ino such that it agrees with the folder name. Rename SSD1306_OLED_HW_I2C.c to SSD1306_OLED_HW_I2C.cpp

Modify the .ino file to your liking and upload as usual.

AVR-GCC environment (advanced)

You'll need the following files in your project folder: SSD1306_OLED_HW_I2C.c, SSD1306_OLED_HW_I2C.h, main.c and Makefile. main.c contains demo code which you can replace with your own.

Assuming the avr-gcc toolchain has been set up properly, you can compile with make all in terminal. If you have a usbasp programmer, the firmware will be automatically uploaded (tested on Mac OS Sierra). If you have a different programmer you will need to either modify the programmer descriptor in the makefile or use avrdude with your custom options.

Reference

The following functions have been implemented in v2.0:

• initialize display d_init();
• clear display d_clear();
• turn off (sleep) d_off();
• turn on (wake up) d_on();
• change brightness (same as contrast) d_contrast (0-255 or 0x00-0xFF);
• display 128x64 bitmap d_draw_bmp (bitmap_array);
  • declare the bitmap_array as const uint8_t bitmap_array [] PROGMEM = { }
  • to obtain a bitmap byte array, use gimp or another editor to make a 128x64 monochrome image, then use http://en.radzio.dxp.pl/bitmap_converter/.
• print string (8x6 ascii font) d_print_str(x coordinate, character row, “string”, bitmap_array or NO_BACKGROUND);
  • x coordinate 0-127
  • character row 0-7
  • if you want the background image to be visible behind the text, specify the name of the bitmap array as the last argument; otherwise use NO_BACKGROUND.
• print variable (integers only) d_print_int(x coordinate, character row, integer or int variable, bitmap_array or NO_BACKGROUND);
  • x coordinate 0-127
  • character row 0-7
  • if you want the background image to be visible behind the text, specify the name of the bitmap array as the last argument; otherwise use NO_BACKGROUND.

List of changes between v1 and v2.0

• made function names lowercase
• moved demonstration code into a separate file
• added ability to display bitmaps
• removed functions for horizontal and vertical lines
• adapted d_print_int and d_print_str to have the ability to preserve the background

If you are interested in v1 of the library, I no longer have it, but you can find an improved version at https://github.com/greenonline/SSD1306_OLED_HW_I2C_LIB

Credits from the original SSD1306 library:

Copyright (c) 2016 Neven Boyanov, Tinusaur Team. All Rights Reserved. Distributed as open source software under MIT License, see LICENSE.txt file. Please, as a favor, retain the link http://tinusaur.org to The Tinusaur Project. Source code available at: https://bitbucket.org/tinusaur/ssd1306xled

NUM2STR - Function to handle the conversion of numeric vales to strings. @created 2014-12-18 @author Neven Boyanov @version 2016-04-17 (last modified) NOTE: This implementation is borrowed from the LCDDDD library. Original source code at: https://bitbucket.org/boyanov/avr/src/default/lcdddd/src/lcdddd/lcdddd.h