A simple E-Paper display library with common base class and separate IO class for Arduino.

It needs up to 30kB available RAM to buffer the black/white image for the SPI displays. ESP8266 or STM32 systems have just enough free RAM, e.g. Arduino Due, ESP8266 or STM32. I use it with Wemos D1 mini, STM32F103RB-Nucleo, and STMF103C8T6 (BluePill) systems.

• Paged Drawing is available to cope with RAM restriction on AVR processors.

• Waveshare e-paper displays with SPI: http://forum.arduino.cc/index.php?topic=487007.0
• Good Dispay ePaper for Arduino : https://forum.arduino.cc/index.php?topic=436411.0

Initial support is for E-Paper displays from Dalian Good Display Inc. with SPI:

These display can be connected using the DESTM32-S2 connection board to power and SPI.

• GDEW042T2 4.2 inch 400 x 300 pixel black/white
• GDEW075T8 7.5 inch 640 x 384 pixel black/white
• Added GDEP015OC1 1.54 inch 200 x 200 pixel black/white
• Added GDEW027C44 2.7 inch 176 x 264 pixel black/white/red
• Added example IoT_SHT31LP_Example_1.54inchEPD
• Added GDE0213B1 2.13 inch 128 x 250 pixel black/white
• Added GDEH029A1 2.9 inch 128 x 296 pixel black/white

The following classes can be used with Waveshare e-Paper displays:

• The GxGDEP015OC1 class can be used with Waveshare 1.54inch e-Paper SPI display.
• The GxGDE0213B1 class can be used with Waveshare 2.13inch e-Paper SPI display.
• The GxGDEH029A1 class can be used with Waveshare 2.9inch e-Paper SPI display.
• The GxGDEW042T2 class can be used with Waveshare 4.2inch e-Paper SPI display.
• The GxGDEW027C44 class may be usable with the Waveshare 264x176 2.7inch 3 color E-Ink display.

Support for partial update and paged drawing (AVR, low RAM).

• To use on AVR (UNO, NANO) Arduino IDE 1.8.x is required (optimizing linker) for code space.

mapping suggestion from Waveshare SPI e-Paper to Wemos D1 mini:

• BUSY -> D2, RST -> D4, DC -> D3, CS -> D8, CLK -> D5, DIN -> D7, GND -> GND, 3.3V -> 3.3V

mapping suggestion from Waveshare SPI e-Paper to ESP8266 NodeMCU:

• BUSY -> D2, RST -> D4, DC -> D3, CS -> D8, CLK -> D5, DIN -> D7, GND -> GND, 3.3V -> 3.3V

mapping suggestion from Waveshare SPI e-Paper to generic ESP8266:

• BUSY -> GPIO4, RST -> GPIO2, DC -> GPIO0, CS -> GPIO15, CLK -> GPIO14, DIN -> GPIO13, GND -> GND, 3.3V -> 3.3V

mapping suggestion (by G6EJD) from Waveshare SPI e-Paper to ESP8266 Huzzah:

• BUSY -> 03, RST -> 15, DC -> 02, CS -> 00, CLK -> 14, DIN -> 13, GND -> GND, 3.3V -> 3.3V

new mapping suggestion for STM32F1, e.g. STM32F103C8T6 "BluePill"

• BUSY -> A1, RST -> A2, DC -> A3, CS-> A4, CLK -> A5, DIN -> A7

mapping example for AVR, UNO, NANO etc.:

• BUSY -> 7, RST -> 9, DC -> 8, C S-> 10, CLK -> 13, DIN -> 11

Added classes for Waveshare and Good Display black / white / red SPI e-Paper displays:

• GxGDEW0154Z04 1.54 inch 200 x 200 3 color SPI display
• GxGDEW0213Z16 2.13 inch 104 x 212 3 color SPI display
• GxGDEW029Z10 2.9 inch 128 x 296 3 color SPI display

Added Fast Partial Update variant GxGDEW042T2_FPU for 4.2 inch black/white display

• NOTE: This Fast Partial Update variant works with an experimental partial update waveform table
• Side effects and life expectancy with this LUT are unknown, as it is NOT from the manufacturer!

Added Support for multiple e-paper displays on one Arduino (with enough RAM, e.g. ESP32)

Added GxGDEW042Z15 display class for 4.2inch 400 x 300 black / white / red e-Paper

• The display class supports partial update, but display update is full screen (controller issue)

Added GxGDEW027W3 display class for 2.7inch 264 x 176 black / white e-Paper

• added GxEPD_SD_BitmapExample

• added "no BUSY" support to GxGDEP015OC1 for Heltec E-Paper 1.54" b/w without BUSY
• set BUSY parameter to -1 for Heltec E-Paper 1.54" b/w without BUSY

• added GxGDEW0583T7 for 5.83" b/w 600x448 display
• my GDEW0583T7 panel has a refresh time of ~15 seconds
• please report if you got this display with faster refresh time, or got faster driver or demo

• fix GxGDEW042T2 to avoid double full refresh after reset (deep sleep wakeup)

• added GxGDEW0154Z17 for 1.54" 3-color 152x152 display
• NOT tested on GDEW0154Z17, I don't have this display
• tested on 2.9" 3-color display, same controller IL0373
• use GxEPD_RED to get yellow on yellow 3-color e-paper

• new version for 7.5" 3-color display GxGDEW075Z09
• GxGDEW075Z09 runs with full buffer on ESP32, Arduino Due, STM32F4
• runs with reduced buffer on ESP8266, STM32F1, AVR : will show buffer content as stripes
• supports paged display on AVR, ESP8266, STM32F1

• Serial Diagnostic Output selectable by parameter of init() call:
• void init(uint32_t serial_diag_bitrate = 0); // = 0 : disabled

• additional font support, e.g. from https://github.com/olikraus/U8g2_for_Adafruit_GFX

• fixes and cleanup

• GxFont_GFX : Font Rendering Graphics Switch and Bridge Class

• GDE060BA 6 inch 800 x 600 pixel 4 gray level
• GDEW080T5 8 inch 1024 x 768 pixel 4 gray level

These display can be used with the red DESTM32-L evaluation board, it has 1MB FSMC SRAM on board.

The library classes for these display can be used with the STM32GENERIC package for Arduino IDE.

• Added GxGDE043A2 4.3 inch 800 x 600 pixel 4 gray level, with unresolved degradation issue