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 having the same panels

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 3k3 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
note that Waveshare boards with "clever" reset circuit may need shortened reset pulse
use init(115200, true, 2, false) for Waveshare boards with "clever" reset circuit
note that Waveshare boards with "clever" reset circuit need 1k pull-up on RST on ESP8266, or different pin
note that the new Waveshare Universal e-Paper Raw Panel Driver HAT Rev 2.3 needs PWR connected to VCC or driven HIGH
see https://www.waveshare.com/wiki/E-Paper_Driver_HAT
some new Waveshare boards also have a PWR control pin, needs be pulled hight

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 can either be done using Adafruit_GFX methods without picture loop or drawCallback
and then calling method display()
or by still using the page loop or drawCallback

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 Display ePaper for Arduino : https://forum.arduino.cc/index.php?topic=436411.0
Note that these topics are closed. Use only for reference.
The Arduino Forum is no longer watched and answered by the Author.
New questions or issues should be posted on https://github.com/ZinggJM/GxEPD2/discussions

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

Note on issues and pull requests

issues should be reported in https://github.com/ZinggJM/GxEPD2/discussions.
issues on GitHub are disabled; there were too many false issues.
pull requests are not welcome, will not be merged.
pull requests can't be disabled, but will be closed.
please place information about interesting fork additions in https://github.com/ZinggJM/GxEPD2/discussions.

Supported SPI e-paper panels from Good Display:

GDEW0102T4 1.02" b/w 80x128, UC8175
DEPG0150BN 1.50" b/w 200x200, SSD1681, e.g. LILYGO® TTGO T5 V2.4.1 1.50 inch
GDEP015OC1 1.54" b/w 200x200, IL3829, no longer available
GDEH0154D67 1.54" b/w 200x200, SSD1681, replacement for GDEP015OC1
GDEW0154T8 1.54" b/w 152x152, UC8151 (IL0373)
GDEW0154M09 1.54" b/w 200x200, JD79653A
GDEW0154M10 1.54" b/w 152x152, UC8151D, DES
GDEY0154D67 1.54" b/w 200x200, SSD1681
GDEW0154Z04 1.54" b/w/r 200x200, IL0376F, no longer available
GDEH0154Z90 1.54" b/w/r 200x200, SSD1681, replacement for GDEW0154Z04
GDEM0154F51H 1.54" 4-color 200x200, JD79660
GDE0213B1 2.13" b/w 122x250, IL3895, phased out
GDEH0213B72 2.13" b/w 122x250, SSD1675A (IL3897), replacement for GDE0213B1
GDEH0213B73 2.13" b/w 122x250, SSD1675B, new replacement for GDE0213B1, GDEH0213B72
GDEM0213B74 2.13" b/w 122x250, SSD1680
GDEW0213I5F 2.13" b/w 104x212, UC8151 (IL0373), flexible
GDEW0213T5D 2.13" b/w 104x212, UC8151 (IL0373)
GDEW0213M21 2.13" b/w 104x212, UC8151 (IL0373), DES
GDEW0213Z16 2.13" b/w/r 104x212, UC8151 (IL0373)
GDEW0213Z19 2.13" b/w/r 104x212, UC8151D
GDEY0213Z98 2.13" b/w/r 122x250, SSD1680
GDEY0213F51 2.13" 4-color 122x250, JD79661
DEPG0213BN 2.13" b/w 122x250, SSD1680, e.g. LILYGO® TTGO T5 V2.3.1 2.13 inch
GDEY0213B74 2.13" b/w 122x250, SSD1680
GDEW026T0 2.6" b/w 152x296, UC8151 (IL0373)
GDEW026M01 2.6" b/w 152x296, UC8151 (IL0373), DES
DEPG0266BN 2.66" b/w 152x296, SSD1680, e.g. LILYGO® TTGO T5 2.66 inch
GDEY0266Z90 2.66" b/w/r 152x296, SSD1680
GDEY0266F51H 2.66" 4-color 184x460, JD79667
GDEW027C44 2.7" b/w/r 176x264, IL91874
GDEW027W3 2.7" b/w 176x264, EK79652 (IL91874)
GDEY027T91 2.7" b/w 176x264, SSD1680
GDEH029A1 2.9" b/w 128x296, SSD1608 (IL3820)
GDEW029T5 2.9" b/w 128x296, UC8151 (IL0373)
GDEW029T5D 2.9" b/w 128x296, UC8151D
GDEW029I6FD 2.9" b/w 128x296, UC8151D, flexible
GDEM029T94 2.9" b/w 128x296, SSD1680
GDEW029M06 2.9" b/w 128x296, UC8151D, DES
GDEW029Z10 2.9" b/w/r 128x296, UC8151 (IL0373)
GDEH029Z13 2.9" b/w/r 128x296, UC8151D
GDEM029C90 2.9" b/w/y 128x296, SSD1680
DEPG0290BS 2.9" b/w 128x296, SSD1680, e.g. LILYGO® TTGO T5 V2.4.1 2.9"
GDEY029T94 2.9" b/w 128x296, SSD1680
GDEY029T71H 2.9" b/w 168x384, SSD1685
GDEY029F51H 2.9" 4-color 168x384, JD79667
Waveshare3inch4color 3.0" 4-color 168x400
GDEQ031T10 3.1" b/w 240x320, UC8253
GDEM035F51 3.5" 4-color 184x384, JD79667
GDEY037T03 3.7" b/w 240x416, UC8253
ED037TC1 3.7" b/w 280x480, SSD1677, Waveshare 3.7"
GDEW0371W7 3.7" b/w 240x416, UC8171 (IL0324)
GDEM0397T81 3.97" b/w 480x800, SSD1677
GDEM0397F81 3.97" 4-color, 800x480, SSD2677
GDEW042T2 4.2" b/w 400x300, UC8176 (IL0398)
GDEW042M01 4.2" b/w 400x300, UC8176 (IL0398), DES
GDEW042Z15 4.2" b/w/r 400x300, UC8176 (IL0398)
GDEQ042Z21 4.2" b/w/r 400x300, UC8276, (Waveshare V2)
GDEY042Z98 4.2" b/w/r 400x300, SSD1683
GDEY042T81 4.2" b/w 400x300, SSD1683
GDEY0420F51 4.2" 4-color 400x300, HX8717
GDEQ0426T82 4.26" b/w 800x480, SSD1677
Waveshare437inch4color Waveshare 4.37" 4-color e-paper display 512x368
ACeP565 5.65" Waveshare 5.65" 7-color e-paper display 600x448
GDEP0565D90 5.65" 7-color 600x448
GDEH0576T81 5.76" b/w 920x680, SSD2677
GDEY0579T93 5.79" b/w 792x272, SSD1683
GDEY0579Z93 5.79" b/w/r 792x272, SSD1683
GDEY0579F51 5.79" 4-color 792x272, HX8717
GDEW0583T7 5.83" b/w 600x448, UC8159c (IL0371)
GDEW0583T8 5.83" b/w 648x480, EK79655 (GD7965)
GDEW0583Z83 5.83" b/w/r 648x480, EK79655 (GD7965)
GDEQ0583T31 5.83" b/w 648x480, UC8179
GDEQ0583Z31 5.83" b/w/r 648x480, UC8179C
GDEY073D46 7.3" 800x480 7-color
GDEP073E01 7.3" 800x480 7-color
ACeP730 7.3" Waveshare 7-color e-paper display 800x480, PhotoPainter
GDEW075T8 7.5" b/w 640x384, UC8159c (IL0371)
GDEW075T7 7.5" b/w 800x480, EK79655 (GD7965)
GDEY075T7 7.5" b/w 800x480, UC8179 (GD7965)
GDEW075Z09 7.5" b/w/r 640x384, UC8159c (IL0371)
GDEW075Z08 7.5" b/w/r 800x480, EK79655 (GD7965)
GDEY075Z08 7.5" b/w/r 800x480, UC8179
GDEH075Z90 7.5" b/w/r 880x528, SSD1677
GDEM075F52 7.5" 4-color, 800x480, JD79665AA
GDEM102T91 10.2" b/w 960x640, SSD1677
GDEM1085T51 10.85 b/w 1360x480, JD79686AB
GDEH116T91 11.6" b/w 960x640, SSD1677
GDEY116Z91 11.6" b/w/r 960x640, SSD1677
GDEY116F51 11.6" 4-color 960x640, SSD2677
GDEW1248T3 12.48" b/w 1304x984, UC8179
GDEY1248Z51 12.48" b/w/r 1304x984, UC8179
GDEM133T91 13.3" b/w 960x680, SSD1677
GDEM133Z91 13.3" b/w/r 960x680, SSD1677

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

other supported panels

GYE042A87 4.2" b/w 400x300, SSD1683 (HINK-E042-A07-FPC-A1)
SE0420NQ04 4.2" b/w 400x300, UC8276C (OPM042A2_V1.0)
ED060SCT 6" grey levels, on Waveshare e-Paper IT8951 Driver HAT
ED060KC1 6" grey levels, 1448x1072, on Waveshare e-Paper IT8951 Driver HAT
ED078KC2 7.8" grey levels, 1872x1404, on Waveshare e-Paper IT8951 Driver HAT
ES103TC1 10.3" grey levels, 1872x1404, on Waveshare e-Paper IT8951 Driver HAT

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

I accept panel donations to add support to GxEPD2 only on exception.
I support only panels from known sources that are well documented.
Let me know about interesting panels that fall into this category.
I occasionally buy new panels, but adding support will take as much time as needed.

Version 1.6.9

added support for GDEH0576T81, 5.76" b/w 920x680, SSD2677
the GDEH0576T81 has partial window addressing and partial window refresh
the controller SSD2677 of GDEH0576T81 supports differential refresh with bit interleaved old/new per pixel
the driver GxEPD2_576_GDEH0576T81 supports differential refresh through writeNative with previous/current bitmaps
the new display class GxEPD2_BW_SHM supports GxEPD2 style fast partial update with a shadow buffer for previous
the display class GxEPD2_BW_SHM uses a "malloc" allocated shadow buffer on processors with enough heap space
class GxEPD2_BW_SHM falls back to GxEPD2_BW behavior if "malloc" fails, which results in full refresh on GDEH0576T81
fixed controller name of GDEM0397T81 to SSD1677

Version 1.6.8

added methods writeImageToPrevious and writeImagePartToPrevious to b/w driver classes
added partial update support to GDEP073E01
added partial window addressing to GDEY073D46, partial refresh not usable

Version 1.6.7

added support for GDEW075Z08 fast b/w refresh in new class GxEPD2_750c_GDEW075Z08
GxEPD2_750c_GDEW075Z08 uses a b/w waveform written to registers, none available in OTP
added support for GDEY075Z08 fast b/w refresh in new class GxEPD2_750c_GDEY075Z08
GxEPD2_750c_GDEY075Z08 uses a b/w waveform written to registers, OTP version is faulty
GDEW075Z08 and GDEY075Z08 both have distortion on borders between black and white
therefore narrow or small fonts are barely readable with fast b/w refresh
renamed method writeImagePrevious to writeImageToPrevious
renamed method writeImageNew to writeImageToCurrent

Version 1.6.6

added support for GDEM0154F51H, 1.54" 4-color 200x200, JD79660
added support for GDEM035F51, 3.5" 4-color 184x384, JD79667
added support for GDEM0397F81, 3.97" 4-color, 800x480, SSD2677
added support for GDEM075F52, 7.5" 4-color, 800x480, JD79665AA
added method writeImageToPrevious to class GxEPD2_750_GDEY075T7 and nextPageToPrevious to GxEPD2_BW
renamed class GxEPD2_0579c_GDEY0579F51 to GxEPD2_579c_GDEY0579F51

Version 1.6.5

added support for GDEM0397T81, 3.97" b/w 480x800, SSD1677
fixed GxEPD2_290_T94 partial refresh

Version 1.6.4

added support for GDEY037T03 3.7" b/w 240x416, UC8253

Version 1.6.3

updated GxEPD2_4C.h with WIDTH_VISIBLE (for GDEY0213F51)
updated GxEPD2_154_Z90c.cpp powerOff() handling
updated powerOff() handling for other 3-color displays

Version 1.6.2

fixed support for GDEY029T71H 2.9" b/w 168x384, SSD1685
GxEPD2_WiFi_Example: added direct (non-buffered) BMP download to 7-color displays
some minor fixes

Version 1.6.1

fixed and updated GxEPD2_WiFi_Example

Version 1.6.0

updated support for GDEY029T94: fixed a partial refresh issue
updated support for GDEY042T81: fixed fast full refresh for 2024 panel version
updated support for GDEP073E01: fixed color mapping for its native color values
updated GxEPD2_display_selection_new_style.h: added Arduino Nano Every, Arduino Nano ESP32, Arduino Nano IoT.

Version 1.5.9

added Power Save command (PWS) to GDEY075T7 init (issue with dithered bitmaps)
added support for GDEY0579T93 5.79" b/w 792x272, SSD1683
added support for GDEY0579Z93 5.79" b/w/r 792x272, SSD1683
added support for GDEY0579F51 5.79" 4-color 792x272, HX8717
the GDEY0579F51 has partial window addressing capability,
but of little use, because the controller buffer is modified during refresh
partial window refresh can't be used on GDEY0579F51, refresh is full screen
added support for GDEY042Z98 4.2" b/w/r 400x300, SSD1683
GDEY042Z98 has "fast" full refresh and supports fast b/w partial refresh
added support for GDEP073E01 7.3" 800x480 7-color

Version 1.5.8

added support for GDEP0565D90 5.65" 7-color 600x448
added support for GDEY116F51 11.6" 4-color 960x640, SSD2677
added support for GDEY029T71H 2.9" b/w 168x384, SSD1685

Version 1.5.7

added support for GDEY0213F51 2.13" 4-color 122x250, JD79661
added support for GDEM1085T51 10.85 b/w 1360x480, JD79686AB

Version 1.5.6

version for ongoing fixes and additions
added support for GYE042A87 4.2" b/w 400x300
added support for SE0420NQ04 4.2" b/w 400x300
added support for GDEQ0583Z31 5.83" b/w/r 648x480
added support for GDEM102T91 10.2" b/w 960x640, SSD1677
added support for GDEY116Z91 11.6" b/w/r 960x640, SSD1677
added support for GDEM133T91 13.3" b/w 960x680, SSD1677
added support for GDEM133Z91 13.3" b/w/r 960x680, SSD1677
improved differential refresh for SE0420NQ04
improved full refresh for SE0420NQ04
fixed driver class GxEPD2_213.cpp

Version 1.5.5

updated 7-color driver classes (design cleanup fixed)
note: Waveshare PhotoPainter doesn't work with MBED Pico package
note: use package https://github.com/earlephilhower/arduino-pico for PhotoPainter

Version 1.5.4

added support for GDEQ031T10 3.1" b/w 240x320
updated support for GDEY075T7 7.5" b/w 800x480
renamed driver class GxEPD2_750_YT7 to GxEPD2_750_GDEY075T7
the actual GDEY075T7 panels have fast full refresh capability
added support for Waveshare 7.3" 7-color, driver class GxEPD2_730c_ACeP_730
added support for Waveshare 7.3" 7-color PhotoPainter with RPi Pico RP2040
updated b/w driver classes for SSD controllers
updated 7-color driver classes (design cleanup)

Version 1.5.3

added support for GDEQ0426T82 4.26" b/w 800x480
added support for GDEY0266F51H 2.66" 4-color 184x460
added support for GDEY029F51H 2.9" 4-color 168x384
added support for GDEY0420F51 4.2" 4-color 400x300
added support for Waveshare 3.00" 4-color e-paper display 168x400
updated support for Waveshare 4.37" 4-color e-paper display 512x368
the 4-color displays have partial window addressing and refresh
renamed GDEY042T91 to its new official name GDEY042T81

Version 1.5.2

added support for Waveshare 4.37" 4-color e-paper display 512x368
fixed __has_include test (for packages that don't support __has_include)
added WIDTH_VISIBLE for correct graphics width for 2.13" b/w 122x250
added end() method, to release SPI and reset all pins to INPUT

Version 1.5.1

added support for GDEY0154D67 1.54" b/w 200x200
added support for GDEY0213B74 2.13" b/w 128x250
updated support for GDEY027T91 2.7" b/w 176x264
renamed driver class for GDEY027T91 to GxEPD2_270_GDEY027T91
added support for GDEY029T94 2.9" b/w 128x296
added support for GDEY042T91 4.2" b/w 400x300
added support for GDEQ0583T31 5.83" b/w 648x480
these panels have fast full refresh capability
fast full refresh can be disabled in the class header for low temperature use
added support for GDEY073D46 7.3" 800x480 7-color
all these new panels have been donated by Good Display
added __has_include test to GxEPD2_BW.h, GxEPD2_3C.h, GxEPD2_7C
this allows to remove or put aside unused driver classes for faster compile
several fixes and improvements

Version 1.5.0

added support for GDEY075T7 7.5" b/w 800x480
updated GxEPD2_Example, added HSPI use for Waveshare ESP32 Driver Board
updated GxEPD2_SD_AVR_Example, fixes for BMP handling
updated GxEPD2_SD_Example, fixes for BMP handling, added HSPI use for Waveshare ESP32 Driver Board
updated GxEPD2_SerialFlash_Example, fixes for BMP handling
updated GxEPD2_SerialFlash_Loader, updated https certificates and use
updated GxEPD2_Spiffs_Example, fixes for BMP handling
updated GxEPD2_Spiffs_Loader, updated https certificates and use
added GxEPD2_WiFi_CertStore_Example, use of a BearSSL CertStore on ESP8266, like a browser
added GxEPD2_WiFi_CertStore_Loader, download root certificates (from Mozilla) to ESP8266 flash
updated GxEPD2_WiFi_Example, fixes for BMP handling, updated https certificates and use
updated GxEPD2_WS_ESP32_Driver, added HSPI use for Waveshare ESP32 Driver Board

Version 1.4.9

added missing constructor lines to GxEPD2_display_selection.h
added panel details to comments in GxEPD2_display_selection.h
added panel details to Supported SPI e-paper panels in README.md

Version 1.4.8

added support for GDEY027T91 2.7" b/w 176x264
added support for GDEY1248Z51 12.48" b/w/r 1304x984
fixed name of panel DEPG0150BN
updated certificate and fingerprint for GitHub download in GxEPD2_WiFi_Example

Version 1.4.7

added support for DEPG0150BN 1.50" b/w 200x200, e.g. LILYGO® TTGO T5 V2.4.1 1.50 inch
added support for DEPG0213BN 2.13" b/w 128x250, e.g. LILYGO® TTGO T5 V2.3.1 2.13 inch
added support for DEPG0266BN 2.66" b/w 152x296, e.g. LILYGO® TTGO T5 2.66 inch
added support for DEPG0290BS 2.9" b/w 128x296, e.g. LILYGO® TTGO T5 V2.4.1 2.9"
added support for ES103TC1 10.3" grey levels, 1872x1404, on Waveshare e-Paper IT8951 Driver HAT

Version 1.4.6

added support for GDEY0266Z90 2.66" b/w/r 152x296
added support for GDEW0583Z83 5.83" b/w/r 648x460

Version 1.4.5

added support for GDEY0213Z98 2.13" b/w/r 122x250
tested with LOLIN 2.13" Tri-Color eInk / ePaper 250x122 Display Shield
https://www.aliexpress.com/item/1005003020667903.html

Version 1.4.4

interim update to solve compiler warnings (ALL for GCC for AVR)

Version 1.4.3

added option to select an alternate HW SPI channel and/or SPI settings
by method selectSPI(SPIClass& spi, SPISettings spi_settings) of driver base class GxEPD2_EPD
by calling selectSPI before calling init() of display class
or by calling extended init() method that has these parameters added
tested with RPi Pico RP2040 using Good Display DESPI-PICO connection shield
updated GxEPD2_Example to show use with DESPI-PICO
DESPI-PICO: see https://www.good-display.com/product/393.html

Version 1.4.2

added support for Waveshare 3.7" b/w board and panel ED037TC1
waveform tables for ED037TC1 are taken unmodified from Waveshare demo code
refresh behavior with ED037TC1 with GxEPD2 is not perfect, could not be resolved
ISSUE RESOLVED: RESE needs to be 3 ohms on DESPI-C02 for this panel, Waveshare schematics is wrong
added differential refresh for GDEH116T91, waveform table taken from ED037TC1
differential refresh for GDEH116T91 looks ok; can be disabled with hasFastPartialUpdate = false
increased sustain phase for differential refresh on GDEW042T2

Version 1.4.1

fix for Waveshare "clever" reset circuit: power controller before reset pulse

Version 1.4.0

changed the default reset duration to 10ms instead of 20ms
changed the delay after reset to 10ms or reset duration, whichever is higher, instead of 200ms
added a busyCallback feature, to allow to service periodic actions during wait for BUSY termination
// register a callback function to be called during _waitWhileBusy continuously.
void setBusyCallback(void (*busyCallback)(const void*), const void* busy_callback_parameter = 0);
added example GxEPD2_RotaryUsingBusyCallback.ino

Version 1.3.9

fix for STM32 official package pin number range (int16_t)
fix for refresh(int16_t x, int16_t y, int16_t w, int16_t h) methods screen intersection

Version 1.3.8

added support for GDEQ042Z21 4.2" b/w/r 400x300 panel or Waveshare 4.2" V2 b/w/r board
the Waveshare 4.2" V2 b/w/r board requires the shortened reset pulse
added support for GDEW029I6FD 2.9" b/w 128x296 flexible board
some fixes and improvement for the new style panel selection

Version 1.3.7

added support for GDEW0102T4 1.02" b/w 80x128 panel or Waveshare 1.02" b/w board
the GDEW0102T4 panel has a different connector than the other SPI panels
the GDEW0102T4 panel can be used with the DESPI-C102 connection module
https://buy-lcd.com/products/connection-board-demo-kit-for-102-inch-e-ink-display-despi-c102
my test have been done with the Waveshare 1.02" b/w board

Version 1.3.6

added support for Waveshare 2.9" b/w V2, driver class GxEPD2_290_T94_V2
Waveshare 2.9" b/w V2 uses a GDEM029T94 variant without partial update wft in OTP
driver class GxEPD2_290_T94_V2 uses partial update wft written to registers
added NOTE for RST pull-up on ESP8266 with "clever" reset circuit, or alternate pin

Version 1.3.5

added support for GDEM0213B74 122x250 b/w e-paper panel
added support for ED078KC2, 7.8" grey levels, 1872x1404, on Waveshare e-Paper IT8951 Driver HAT

Version 1.3.4

added support for GDEH116T91 960x640 b/w e-paper panel
GDEH116T91 has only full screen refresh, no wavetable for differential refresh yet
added support for processor Arduino Nano RP2040 Connect to the examples
added general fast b/w refresh for capable 3-color displays GDEW0213Z19, GDEW029Z13
added example GxEPD2x_FastBlackWhiteOnColor.ino for GDEW0213Z19, GDEW029Z13
evaluation of other fast b/w capable 3-color panels may follow

Version 1.3.3

added b/w differential refresh method to GDEW0213Z19
added b/w differential refresh method to GDEW029Z13
up to 100 b/w fast refreshes have been possible (resulting in slightly reddish background)
added experimental example GxEPD2x_MixedTest for proof of concept
GxEPD2x_MixedTest needs enough RAM for 2 GFXCanvas1 objects
general 3-color mixed refresh in GxEPD2 is in evaluation, for capable panels

Version 1.3.2

added support for GDEW0213T5D 104x212 b/w e-paper panel
added support for GDEW029T5D 128x296 b/w e-paper panel
added support for GDEW0213Z19 104x212 b/w/r e-paper panel
added support for GDEW029Z13 128x296 b/w/r e-paper panel
both GDEW0213Z19 and GDEW029Z13 support only full screen refresh (controller issue)

Version 1.3.1

added support for GDEM029C90 128x296 b/w/y e-paper panel
GDEM029C90 has a very long refresh time of about 27 seconds
GDEM029C90 has partial update (window addressing) of controller memory
GDEM029C90 supports only full refresh of screen

Version 1.3.0

added support for GDEM029T94 128x296 b/w e-paper panel
added support for GDEW026M01 152x296 b/w new DES e-paper panel
the new GDEW026M01 DES b/w e-paper panel has higher contrast and wide temperature range
differential refresh (fast partial update) is supported for normal temperature range
disable differential refresh for extended temperatures by setting hasFastPartialUpdate = false;
the differential waveform table for GDEW026M01 is experimental and may need improvement
major update of display selection in the examples to make additions easier:
old style selection is now in separate include files GxEPD2_display_selection.h
and GxEPD2_display_selection_added.h
added new style display selection in include file GxEPD2_display_selection_new_style.h
either selection style can be used. old style is intended for easy copying of constructor lines.

Version 1.2.16

fix for GDEH0154D67, to work independent of OTP version (ping-pong issue)

Version 1.2.15

added support for GDEW0213M21 2.13" 104x212 b/w new DES e-paper panel
added support for GDEW029M06 2.9" 128x296 b/w new DES e-paper panel
added support for GDEW042M01 4.2" 400x300 b/w new DES e-paper panel
these new DES b/w e-paper panels have higher contrast and wide temperature range
differential refresh (fast partial update) is supported for normal temperature range
disable differential refresh for extended temperatures by setting hasFastPartialUpdate = false;
the GDEW042M01 I have is a preliminary version, differential waveform may need update

Version 1.2.14

added support for 6" 1448x1072 ED060KC1 on Waveshare e-Paper IT8951 Driver HAT
fixed GxEPD2_WiFi_Example.ino: new GitHub fingerprint for ESP8266, certificate for ESP32
fixed color discriminator for 7-color display in GxEPD2_7C.h
added multicolor support for 7-color display in GxEPD2_WiFi_Example, GxEPD2_Spiffs_Example,
and GxEPD2_SD_Example, GxEPD2_SerialFlash_Example
fixed paged write to 7-color display controller (transaction and CS handling issue)
some more fixes

Version 1.2.13

added support for GDEH0154Z90 1.54" 200x200 b/w/r, replacement for GDEW0154Z04
GDEH0154Z90 has partial window addressing, but no partial window refresh
added some missing constructor examples, e.g. for IT8951 Driver HAT on Due
cleaned-up wiring information in the examples

Version 1.2.12

fixed GxEPD2_MinimumExample.ino to draw black on white (white on white was invisible)
added example GxEPD2_HelloWorld.ino
updated wiring info and constructor parameters for the actual Waveshare e-Paper ESP8266 Driver Board
added some missing explicit initializers (nobody noticed as compilers usually initialize simple members)

Version 1.2.11

added support for Waveshare 5.65" 7-color e-paper display 600x448
the unknown controller of this display doesn't support partial update, as far as known
7-color graphics support is available with class GxEPD2_7C
7-color graphics support requires paging even on ESP32
7-color graphics support causes heavy paging on Arduino UNO, gets very slow
refresh is quite fast for a color e-paper display: 12 seconds

Version 1.2.10

added support for GDEH075Z90 7.5" b/w/r 880x528
the controller of GDEH075Z90 supports partial update, but refesh is full screen
the controller of GDEH075Z90 doesn't support differential update (not possible on 3-color anyway)
note: the connector of the GDEH075Z90 is mirrored; connects downward on DESPI-C02
added optional init parameter "reset_duration" in ms, same default 20ms as before
reset_duration = 2 may help with "clever" reset circuit of newer boards from Waveshare

Version 1.2.9

added support for GDEW0154T8 1.54" b/w 152x152
added support for GDEW0154M09 1.54" b/w 200x200
added support for GDEW0154M10 1.54" b/w 152x152 DES
added support for GDEW0583T8 5.83" b/w 648x460
added option to use class GFX of library GFX_Root instead of Adafruit_GFX
differential update on GDEW0154M10 is experimental, there is no partial update demo yet

Version 1.2.8

improved transfer speed for the bigger displays (3.71" and up)

Version 1.2.7

fix paged drawing of initial screen on GDEH029A1
sometimes true is false, if applied the wrong way round

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

fixed BMP handling, e.g. for BMPs created by ImageMagick
see also Arduino Forum Topic https://forum.arduino.cc/index.php?topic=642343.0

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