zGxEPD2

GxEPD2

Arduino Display Library for SPI E-Paper Displays

• With full Graphics and Text support using Adafruit_GFX

• For SPI e-paper displays from Dalian Good Display

• and SPI e-paper boards from Waveshare

important note :

• the display panels are for 3.3V supply and 3.3V data lines
• never connect data lines directly to 5V Arduino data pins, use e.g. 4k7/10k resistor divider
• series resistor only is not enough for reliable operation (back-feed effect through protection diodes)
• 4k7/10k resistor divider may not work with flat cable extensions or Waveshare 4.2 board, use level converter then
• do not forget to connect GND
• the actual Waveshare display boards now have level converters and series regulator, safe for 5V
• use 4k7 pull-down on SS for ESP8266 for boards with level converters

Paged Drawing, Picture Loop

• This library uses paged drawing to limit RAM use and cope with missing single pixel update support
• buffer size can be selected in the application by template parameter page_height, see GxEPD2_Example
• Paged drawing is implemented as picture loop, like in U8G2 (Oliver Kraus)
• see https://github.com/olikraus/u8glib/wiki/tpictureloop
• Paged drawing is also available using drawPaged() and drawCallback(), like in GxEPD
• // GxEPD style paged drawing; drawCallback() is called as many times as needed
• void drawPaged(void (*drawCallback)(const void*), const void* pv)
• paged drawing is done using Adafruit_GFX methods inside picture loop or drawCallback

Full Screen Buffer Support

• full screen buffer is selected by setting template parameter page_height to display height
• drawing to full screen buffer is done using Adafruit_GFX methods without picture loop or drawCallback
• and then calling method display()

Low Level Bitmap Drawing Support

• bitmap drawing support to the controller memory and screen is available:
• either through the template class instance methods that forward calls to the base display class
• or directly using an instance of a base display class and calling its methods directly

Supporting Arduino Forum Topics:

• 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

Note on documentation

• GxEPD2 uses Adafruit_GFX for Graphics and Text support, which is well documented there
• GxEPD2 uses meaningful method names, and has some comments in the header files
• consult the header files GxEPD2_BW.h, GxEPD2_3C.h and GxEPD2_GFX.h
• for the concept of paged drawing and picture loop see:
• https://github.com/olikraus/u8glib/wiki/tpictureloop

Supported SPI e-paper panels from Good Display:

• GDEP015OC1 1.54" b/w
• GDEW0154Z04 1.54" b/w/r 200x200
• GDE0213B1 2.13" b/w
• GDEH0213B72 2.13" b/w, replacement for GDE0213B1
• GDEH0213B73 2.13" b/w, new replacement for GDE0213B1, GDEH0213B72
• GDEW0213I5F 2.13" b/w flexible
• GDEW0213Z16 2.13" b/w/r
• GDEH029A1 2.9" b/w
• GDEW029T5 2.9" b/w
• GDEW029Z10 2.9" b/w/r
• GDEW026T0 2.6" b/w
• GDEW027C44 2.7" b/w/r
• GDEW027W3 2.7" b/w
• GDEW0371W7 3.7" b/w
• GDEW042T2 4.2" b/w
• GDEW042Z15 4.2" b/w/r
• GDEW0583T7 5.83" b/w
• GDEW075T8 7.5" b/w
• GDEW075Z09 7.5" b/w/r

• GDEW075Z08 7.5" b/w/r 800x480

  Supported SPI e-paper panels & boards from Waveshare: compare with Good Display, same panel

  other supported panels

• ED060SCT 6" grey levels, on Waveshare e-Paper IT8951 Driver HAT

Version 1.1.10

• added support for GDEH0213B73 2.13" b/w, replacement for GDE0213B1, GDEH0213B72
• added support for GDEW026T0 2.6" b/w 152x256
• added support for GDEW0371W7 3.7" b/w 240x416
• added support for GDEW075Z08 7.5" b/w/r 800x480
• GDEW075Z08 does allow (slow) partial update, set usePartialUpdate = false to disable for better image

• changed 4.2" b/w waveform table, for better result with actual panels

  Version 1.1.9

• note for ESP8266 when using SS for CS: (wiring suggestion)

• connect 4.7k pull-down from GPIO15 to GND if your board or shield has level converters

• fixes for large displays (use uint16_t for buffer index)

  Version 1.1.8

• fix for incomplete download in GxEPD2_WiFi_Example

• added missing method displayWindow() to GxEPD2_GFX base class

• fix and clean up of initial refresh for panels with differential update

• initial refresh needs to be full update, not "fast partial update", for these panels,

• as the screen content may differ from the "previous buffer" content.

• add clean of controller buffer(s) on initial write to controller, for partial update.

  Version 1.1.7

• enhanced support for full buffered, non-paged use, for processors with enough RAM

• use void display(bool partial_update_mode = false); corresponds to update() in GxEPD

• use added void displayWindow(uint16_t x, uint16_t y, uint16_t w, uint16_t h);

• use added writeImagePart(...), drawImagePart(...), used by displayWindow()

• added example GxEPD2_NotPagedExample.ino

• several fixes, e.g. parameter range check in setPartialWindow()

  Version 1.1.6

• added support for GDEH0213B72 2.13" b/w, replacement for GDE0213B1

• changed SPI speed for IT8951 Driver HAT to 24MHz for write, 10MHz for read

• minor fixes, e.g. centering of text bounding box in GxEPD2_Example

  Version 1.1.5

• added support for 6" ED060SCT on Waveshare e-Paper IT8951 Driver HAT

• uses 3.3V data lines, but 5V supply (~80mA active, ~20mA stand-by, sleep doesn't work)

• note: 5V supply needs to be exact and strong; 5V over diode from USB (e.g. Wemos D1 mini) doesn't work!

• note that the IT8951 Driver HAT is panel specific, with flash parameterized by supplier

• this is an initial version

  Version 1.1.4+

• added GxEPD2_WS_ESP32_Driver example for Waveshare ESP32 Driver Board

  Version 1.1.4

• eliminated double refresh for "fast partial update"

• moved wavetables to the driver classes

• added one explicit drawImage(...) and writeImage(...) method (for removed default paramter values for 1.1.3)

• added init method with added parameter initial, for re-init after processor deep sleep wakeup

• added init parameter pulldown_rst_mode, for special RST handling (not needed for waveshare shield)

  Version 1.1.3

• fixed wavetables for GDEW029T5 and GDEW0213I5F

• fixed drawImage(...) overloaded methods signature matching ambiguity

  Version 1.1.2

• added support for GDEW029T5

• fixed (added) clipping for partial window

• fixed (added) powerOff() after full update (partial update keeps power on)

• added hibernate() for minimum power use by displays that support it

  Version 1.1.1

• 2.7" b/w GDEW027W3 with fast partial update support, based on new demo code wavetable

• mapping suggestion added for Arduino MEGA

• NOTE: use voltage divider resistors for 5V Arduinos, series resistor is not reliable enough

• ConnectingHardware.md updated

  Version 1.1.0

• added support for GDEW0213I5F for 2.13" b/w 104x212 flexible display

• updated GxEPD2_WiFi_Example and GxEPD2_Spiffs_Loader to use BearSSL on ESP8266, for large bitmap downloads

  Version 1.0.9

• add GxEPD2_U8G2_Fonts_Example, e.g. for use of Umlauts ÄÖÜäéöü

• NOTE: you need to SAVE the modified example to a saveable location for UTF-8 characters to work

  Version 1.0.8

• add GxEPD2_SD_AVR_boards_added.h to GxEPD2_SD_AVR_Example

• with example definitions for non-AVR boards (low level display class use example)

  Version 1.0.7

• add GxEPD2_boards_added.h to GxEPD2_Example

• with example definitions for Arduino DUE and MKR1000

  Version 1.0.6

• add buffered drawing option to GxEPD2_WiFi_Example

• allows use with 1.54" 3-color 200x200 display, may also be useful for small bitmaps

  Version 1.0.5

• add buffered drawing option to GxEPD2_SD_Example and GxEPD2_Spiffs_Example

• allows use with 1.54" 3-color 200x200 display, may also be useful for small bitmaps

  Version 1.0.4

• add GxEPD2_GFX base class support (optional, selectable, uses slightly more code)

• base class GxEPD2_GFX can be used to pass references or pointers to the display instance as parameter

• add GxEPD2_GFX_MultiDisplayExample, uses GxEPD2_GFX reference parameter

• modify GxEPD2_MultiDisplayExample for ESP8266 (template issue: class expected instead of typename)

  Version 1.0.3

• fix GxEPD2_SD_Example & GxEPD2_SD_AVR_Example

• add GxEPD2_MultiDisplayExample (preliminary version)

  Version 1.0.2

• initial release version 1.0.2

• tested with ESP8266, ESP32, STM32F103C8T6, AVR Arduino (Pro Mini 3.3V)

• 1.54" 3-color GxEPD2_154c can be used with paging for AVR

• wave tables in program space, 4.2" b/w can be used with GxEPD2_SD_AVR_Example

• issues enabled and welcome, please use Forum Topic for enhancement suggestions

  Version 1.0.1

• pre-release test version

• GxEPD2_SD_AVR_Example added, has no graphics buffer to reduce RAM usage (base display class use)

• issues disabled so far, use Arduino Forum Topics instead

• in this version 1.54" 3-color GxEPD2_154c can only be used with full size buffer (or with no buffer base display class)

  Version 1.0.0

• preliminary version, under construction