/GxEPD2

Arduino Display Library for SPI E-Paper Displays

Primary LanguageCGNU General Public License v3.0GPL-3.0

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
  • note that 7.5" e-paper displays don't work reliable if fed from 3.3V Arduino pin

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:

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
  • GDEH0154D67 1.54" b/w, replacement for GDEP015OC1
  • 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
  • GDEW075T7 7.5" b/w 800x480
  • GDEW075Z09 7.5" b/w/r
  • GDEW075Z08 7.5" b/w/r 800x480
  • GDEW1248T3 12.48 b/w 1304x984

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

I can and will only support e-paper panels I have!

  • promotion panels from suppliers are welcome, to add support to GxEPD2
  • donation panels from users are welcome, to add support to GxEPD2

Version 1.2.6

  • slightly improved differential refresh for GDEW1248T3
  • minor fixes

Version 1.2.5

  • added support for GDEW1248T3 12.84" b/w panel on Waveshare 12.48 e-paper display frame
  • tested with Waveshare Epaper ESP32 Driver Board mounted on connection board
  • tested with Arduino UNO mounted on connection board, is extremely slow
  • doesn't work with Arduino MEGA on connection board with switch set to ICSP and pins bent out of way, reason unknown
  • not tested with other processors
  • caution: wiring connector is on 5V side of level converters!

Version 1.2.4

  • added support for GDEH0154D67 1.54" b/w, replacement for GDEP015OC1
  • added GxEPD2_SerialFlash_Loader, WiFi bitmap downloader for SPI-flash
  • added GxEPD2_SerialFlash_Example, SPI-flash example, e.g. for Winbond 25Q16BVSIG
  • minor fixes and comment cleanups
  • fix refresh(false) in upper layer: add powerOff() after full refresh

Version 1.2.3

  • fixed partial update for 2.13" 3-color and 2.9" 3-color e-paper
  • partial update can be disabled with attribute usePartialUpdateWindow = false
  • added GxEPD2_GFX_Example to show uses of GxEPD2_GFX base class
  • replaced GxEPD2_MultiDisplayExample code, same code as GxEPD2_GFX_MultiDisplayExample
  • added extras/examples/GxEPD2_T_MultiDisplayExample, alternate example using template functions
  • major and minor fixes, such as typos that survived too long

Version 1.2.2

Version 1.2.1

  • added support for GDEW075T7 7.5" b/w 800x480
  • GDEW075T7 has differential update (1.6s) using a charge balancing waveform
  • added optional SW SPI support, see /extras/sw_spi/README
  • added /extras/tests/GxEPD2_RefreshTests/GxEPD2_RefreshTests.ino, for waveform tuning
  • minor fixes
  • note that 7.5" e-paper displays don't work reliable if fed from 3.3V Arduino pin

Version 1.2.0

  • added "fast partial update" (differential update) for GDEW0371W7 3.7" b/w 240x416
  • improved differential update waveform for GDEW026T0 2.6" b/w 152x256
  • fixed init code & improved differential update for GDEW042T2 4.2" b/w 300x400
  • note that all differential refresh waveforms are a compromise (ghosting, big font use)
  • parameters for differential waveform for these display can easily be changed for experimenting
  • GDEW042T2 would have greyed background without sustain phase
  • GDEW042T2 needs multiple full refreshes after extended use of partial updates

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