uDisplay

2D Display controller library for low spec MCU'S

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Key features

• Intented to run on many embbed c compilers
• Lightweight/Portable implementation using only C and CMake
• Buffer-less rendering (main library goal)
• Generated header only library
• I2C and SPI hardware/software implementations

Example

• Initialze uDisplay

static inline void Initialize()
{
   //Configures uDisplay renderer in this order: protocol/display_driver/address
   uDRenderConfig config = { &uDisplay_UnderlyingProtocol_I2C_Software, &uDisplay_SSD1306Driver, 0x78};

   //Configures uDisplay rendering
   uDisplayRenderer.Initialize(&config);
}

• Font rendering test

//Basic font rendering 
static inline void FontRenderingTest()
{
  //uD_DefaultFont is the built-in font descriptor
  uDisplayRenderer.SetFont(&uD_DefaultFont);

  //This method draws an string at the current origin
  uDisplayRenderer.DrawString("uDisplay:");
  
  //Tries to render 96 characters (if implemented)
  uint8_t charIndex = 32;
  for (; charIndex < 96 * uD_DefaultFont.width; charIndex++)
  {
    uDisplayRenderer.DrawChar(charIndex);
  }
}

Running example on attiny85

• Check uDisplayTest.c for more detailed examples

Dependencies

• cmake
• avr-gnu toolchain
• avrdude

Ubuntu:

sudo apt-get install gcc-avr binutils-avr gdb-avr avr-libc avrdude

Library development states

• TODO

  • Needs to be done lol

• WIP

  • work in progress...

• FUNCTIONAL

  • Has minimal functionality
  • Barely functional

• WOP: WORKING ON PLATFORM

  • Stable code from some specific platform

• RELEASE

  • Stable code
  • Works on all devices and architectures...

uDisplay drivers

DISPLAY CONTROLLER	PROTOCOL	STATUS
SSD1306	I2C	FUNCTIONAL
ST7789	SPI	TODO
ST7735R	SPI	TODO
ILI9341	SPI	TODO

uDisplay MCU compatibility

MCU	ARCH	STATUS
ATmega328P	AVR	TODO
ATTiny85	AVR	FUNCTIONAL
AT89S52	8051	TODO
PIC16F877A	PIC	TODO
STM32F103C8T6	ARM	TODO

uDisplay road map

• 1.0 (WIP)

  • Basic batch rendering
  • Dedicated frame buffer or bufferles rendering
  • Helper rendering functions (generic display built-ins)
    • Clear display
    • Rendering regions (colum and pages configuration)
    • Content scrolling
  • Basic in-memory font rendering
  • Device compatibility
    • ATTINY85
    • ATMEGA328P
  • Display drivers
    • SSD1306
    • SST7789
  • uDisplay benchmarking module - FPS indicator - Latency indicator
  • Header only library (Generated)

• 1.1 (FUTURE-RELEASE)

  • AVR C code optimizations
  • Display drivers
    • ILI9341
  • Touch drivers module
    • ILI9341 touch screen driver
  • Device compatibility
    • STM32 (ARM CORTEX M0)
  • Multiple Screens running on the same library instance (uDisplay factory)

OPTIONAL FEATURES

• 1.X (FUTURE-RELEASE)
  • Video rendering
    • too complex??? idk, let's find out...
  • Pseudo threads for uDisplay (uThreads library)
    • Software implementation
    • Harware implementation using timmers and interrupts

Authors and

• Repo owner
• You

Resources used to implement uDisplay (REFERENCES)

• [AVR Optimization tips and tricks] (https://ww1.microchip.com/downloads/en/AppNotes/doc8453.pdf)
• [Open GL pixmap fonts rendering] (https://courses.cs.washington.edu/courses/cse457/98a/tech/OpenGL/font.c)