C library for SSD1306 OLED Driver
Go to file
2024-09-05 14:24:10 +02:00
img Add new hw connection 2024-09-05 13:07:27 +02:00
lib Back to v2.0.0 2024-09-05 13:58:48 +02:00
.gitignore Create .gitignore 2022-11-24 22:38:29 +01:00
LICENSE Initial commit 2020-10-13 10:44:23 +02:00
main.c Add drawLine horizontal, vertical lines 2024-09-05 13:27:38 +02:00
Makefile Add Adafuit Init Command List for testing purpose 0.91 / 128x32 oled 2023-12-19 22:43:35 +01:00
README.md Update Readme 2024-09-05 14:24:10 +02:00

C Library for SSD1306 0.96" OLED display

SSD1306 Description

Detailed information are described in Datasheet SSD1306.

Library

C library is aimed for driving 0.96" OLED display with SSD1306 driver 128x64 or 128x32 version through TWI's (I2C). Settings for particular versions:

  • 128x64 version
    • command argument SSD1306_SET_MUX_RATIO set to 0x3F (ssd1306.c)
    • command argument SSD1306_COM_PIN_CONF set to 0x12 (ssd1306.c)
    • END_PAGE_ADDR set to 7 (ssd1306.h)
  • 128x32 version
    • command argument SSD1306_SET_MUX_RATIO set to 0x1F (ssd1306.c)
    • command argument SSD1306_COM_PIN_CONF set to 0x02 (ssd1306.c)
    • END_PAGE_ADDR set to 3 (ssd1306.h)

Versions

  • 1.0 - basic functions. The first publication.
  • 2.0 - more changes:
  • 3.0 - simplified alphanumeric version
    • displaying alphanumeric characters
    • for one display applicable
    • only few RAM bytes consumption
    • !!! no graphic functions like drawLine
  • 3.1 - simplified version with draw lines
    • displaying alphanumeric characters with graphic functions like drawLine vertical & horizontal
    • for one display applicable
    • only few RAM bytes consumption
    • horizontal scroll function added

Dependencies

Font.c can be modified according to application requirements with form defined in font.c. Maximal permissible horizontal dimension is 8 bits.

Usage

Prior defined for MCU Atmega328p / Atmega8 / Atmega16. Need to be carefull with TWI ports definition.

PORT Atmega16 Atmega8 / Atmega328
SCL PC0 PC5
SDA PC1 PC4

Picture of hardware connection

Hardware connection

Tested

Library was tested and proved with 0.96″ 128x64 and 0.91" 128x32 OLED Display (SSD1306 driver) and Arduino UNO R3. The Arduino was without a bootloader installed, it was only raw Atmega328P microcontroller. Communication was done through I2C (TWI) interface of Arduino UNO R3. This hardware configuration was chosen for simplicity.

Init OLED Sequence

Init sequence OLED display was defined mainly according to page 64 (next to last page) of Datasheet SSD1306.

Flowchart

// +---------------------------+
// |      Software Reset       |  // not tested yet, @source https://github.com/SmingHub/Sming/issues/501
// +---------------------------+
// |           0xE4            |
// +---------------------------+
//              ||
// +---------------------------+
// |        DISPLAY OFF        |
// +---------------------------+
// |           0xAE            |
// +---------------------------+
//              ||
// +---------------------------+
// |       Set MUX Ratio       |
// +---------------------------+
// |           0xA8            |
// |           0x3F            |
// +---------------------------+
//              ||
// +---------------------------+
// |   Set Memory Addr  Mode   |
// +---------------------------+
// |           0x20            |
// |           0x00            |
// +---------------------------+
//              ||
// +---------------------------+
// |      Set Start Line       |
// +---------------------------+
// |           0x40            |
// +---------------------------+
//              ||
// +---------------------------+
// |    Set Display Offset     |
// +---------------------------+
// |           0xD3            |
// |           0x00            |
// +---------------------------+
//              ||
// +---------------------------+
// |     Set Segment Remap     |
// +---------------------------+
// |       0xA0 or 0xA1        |
// +---------------------------+
//              ||
// +---------------------------+
// |   Set COM Output Scan     |
// |        Direction          |
// +---------------------------+
// |       0xC0 or 0xC8        |
// +---------------------------+
//              ||
// +---------------------------+
// |   Set COM Pins hardware   |
// |       configuration       |
// +---------------------------+
// |           0xDA            |
// |      0x12 for 128x64      |
// |      0x02 for 128x32      |
// +---------------------------+
//              ||
// +---------------------------+
// |   Set Contrast Control    |
// +---------------------------+
// |           0x81            |
// |           0x7F            |
// +---------------------------+
//              ||
// +---------------------------+
// | Disable Entire Display On |
// +---------------------------+
// |           0xA4            |
// +---------------------------+
//              ||
// +---------------------------+
// |    Set Normal Display     |
// +---------------------------+
// |           0xA6            |
// +---------------------------+
//              ||
// +---------------------------+
// |  Set OSC Frequency Fosc   |
// +---------------------------+
// |           0xD5            |
// |           0x80            |
// +---------------------------+
//              ||
// +---------------------------+
// |     Enable charge pump    |
// |         regulator         |
// +---------------------------+
// |           0x8D            |
// |           0x14            |
// +---------------------------+
//              ||
// +---------------------------+
// |     Deactivate Scroll     |
// +---------------------------+
// |           0x2E            |
// +---------------------------+
//              ||
// +---------------------------+
// |        Display On         |
// +---------------------------+
// |           0xAF            |
// +---------------------------+

Functions

Demonstration version v1.0.0

Demonstration version v2.0.0

Demonstration version v3.0.0

Acknowledgement