10.3inch e-Paper HAT (D)

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10.3inch e-Paper raw Panel

1872 × 1404, 10.3inch EPD panel without driver board
10.3inch e-paper HAT

1872 × 1404, 10.3inch EPD HAT for Raspberry Pi, USB/SPI/I80/I2C interface




  • This product is a flexible e-Paper HAT (D), 10.3 inches, with a resolution of 1872×1404. It equips with IT8951 as the controller, can be controlled by USB/SPI/I80 interface, and supports partial refresh.
  • Compared with ordinary e-Paper screens, it is thinner and lighter.
  • It has the advantages of low power consumption, wide viewing angle, and clear display after power failure. It is often used in display applications such as e-book readers, ink screen displays, and industrial instruments.
  • As the screen of 10.3inch e-Paper is large, the glass panel and FPC are fragile, please be careful when using it for developing. we recommend you reinforce the FPC with scotch tape when developing. Please connect all the cables before powering the device, the device cannot support a hot plug.
  • There are two versions: raw panel and HAT. The driver board (IT8951) is required for the raw panel. If you are the first time buying this e-paper, we recommend you choose the HAT version which comes with the driver board.


  • No backlight, keeps displaying last content for a long time even when power down
  • Low power consumption, basically power is only required for refreshing
  • Based on Raspberry Pi 40PIN GPIO interface design, suitable for Raspberry Pi series motherboards
  • USB/SPI/I80/I2C interface, for connecting with host boards like Raspberry Pi/Nucleo, etc.
  • Comes with development resources and manual (examples for Raspberry Pi/STM32)


  • Operating voltage: 5V
  • Interface: USB/SPI/I80/I2C
  • Outline dimension: 227.7mm × 165.8mm × 0.647mm
  • Display size: 209.664mm × 157.248mm
  • Dot pitch: 0.112mm × 0.112mm
  • Resolution: 1872 × 1404
  • Display color: black, white
  • Gray scale: 2-16 (1-4 bit)
  • Full refresh time: 450ms
  • Total refresh power: 1.2W(typ.)
  • Total standby power: 0.1W(typ.)
  • Viewing angle: >170°

Working principle

This product is an E-paper device adopting the image display technology of Microencapsulated Electrophoretic Display, MED. The initial approach is to create tiny spheres, in which the charged color pigments are suspending in the transparent oil and would move depending on the electronic charge. The E-paper screen display patterns by reflecting the ambient light, so it has no background light requirement. Under ambient light, the E-paper screen still has high visibility with a wide viewing angle of 180 degrees. It is the ideal choice for E-reading.(Note that the e-Paper cannot support updating directly under sunlight)

How to use

Working with Windows PC

  • Connect 10.3inch e-paper to IT8951 driver board as below


  • Connect USB interface of IT8951 driver board to PC
  • Download and open E-LINK-TCON-DEMO software
  • Click connect as below


  • Check option "AutoSet", then click "Open File" to open one picture for display. Browse diagram will be opened, and you should click "OK"


  • Click "display" to refresh the picture


Working with Raspberry Pi

  • Step 1:Insert IT8951 driver board to GPIO of Raspberry Pi, Connect e-Paper to the driver board
You can also connecting by wires
Connect to Raspberry Pi via SPI
IT8951 Driver HAT Raspberry Pi (BCM) Description'
5V 5V 5V power input
GND GND Ground
SCK P11 SCK Pin of SPI
CS P8 Chip selection of SPI (Low active)
RST P17 Reset pin (Low active)
HRDY P24 Busy stats pin (Low when busy)
  • Step 2: Make sure you have switched to SPI mode
  • Step 3: Download and install BCM2835 librariesto your Raspberry Pi
You can also download the newest bcm2835 library from its official website http://www.airspayce.com/mikem/bcm2835/
Copy the library you download to Raspberry Pi and install it withe commands below. You can also following the instruction on its website above
tar zxvf bcm2835-1.xx.tar.gz
cd bcm2835-1.xx
sudo make check
sudo make install
Enable spi2.png
  • Step 4: Enable SPI

The Raspberry Pi uses SPI to drive the IT8951 and then drives the ink screen. First, you need to open the SPI. The way to open it is as follows:
Open a terminal command line and enter the command:

sudo raspi-config

Then execute Interfacing Options->P4->SPI->Yes, as shown in the following figure:

  • Step 4: Download Demo codes of 10.3inch e-Paper HAT and test

Download and compile the Demo program, and execute the following commands to download and compile:

Method 1: Download from our official website, it is recommended to use

sudo apt-get install p7zip-full
sudo wget https://www.waveshare.net/w/upload/8/80/IT8951_20200319_Release.7z
7z x IT8951_20200319_Release.7z -O./IT8951
cd IT8951/
sudo make clean
sudo make -j4

Method2: Download from Github

git clone https://github.com/waveshare/IT8951-ePaper.git
cd IT8951-ePaper/Raspberry
sudo make clean
sudo make -j4
  • Check the VCOM data from the FPC
  • Run the example and use the VCOM value as a parameter as well as number 0
sudo ./epd -2.51 0
  • Expected result
    1. Display 16 gray bars in partial mode
    2. Draw figures and strings
    3. Display pictures in 1bp, 2bp, and 4bp modes
    4. Fast updating in A2 mode
    5. Display a gif
    6. Dispaly a demo for calculating the framerate
    7. Clear the display in Init mode

Working with STM32

Driver interface selection

  • Drive by SPI mode (recommended), the advantage is that it occupies less pins, the drive mode is simple, and the communication speed can meet the needs of most scenarios.
  • Adopt 180 mode drive (I80 interface is only considered when the SPI interface communication speed does not meet the application requirements), the advantage is that the drive mode is relatively simple, the communication speed is very fast, but it occupies a lot of pins.
  • Adopt I2C driver (not recommended, the communication speed is very slow).

Driver board selection
Since IT8951 needs to occupy a relatively large RAM space, the general STM32 single-chip microcomputer can not directly satisfy it, and additional chips such as SDRAM are required for RAM expansion. For the test here, we use Open429I as the test board, and its onboard IS42S16400J (64-MBIT) SDRAM can fully meet the requirements of driving 10.3inch e- paper HAT.


1) Hardware connection

Connect to STM32F429IGT6 (SPI)
IT8951 STM32 Description
5V 5V 5V Power input
GND GND Ground
MISO PE13 Data output
MOSI PE14 Data input
SCK PE12 Clock input
CS PE11 Chip select (Low active)
RST PC5 Reset (Low for reset)
HRDY PA7 BUSY state output (Low for busy)

2) Set the DIP switch to SPI mode


3) Download demo code and test

You can download the Demo code

Open the project with keil: Open429I-IT8951-Demo\Project\IT8951\MDK-ARM\Project.uvproj

Compile it, then open IT8951.h, check if SPI mode is enabled. Compile it again and download to your board.


After downloading, the information will be printed as below (115200, 8N1)



1) Hardware connection

Connect to STM32F429IGT6 (I80)
IT8951 STM32 Description
Vcc 5V 5V Power input
GND GND Ground
DBUS0~DBUS15 PB0~PB15 Data pins
HWE PC1 Write enable (Low active)
D/C PC7 Data/Command (Low for command)
CSEL PC6 Chip select (Low active)
HRD PC3 Read enable (Low for active)
RST PC0 Reset (Low for reset)
BUSY PA7 Busy state output (Low for busy)

2) Set the DIP switch to I80 mode


3) Display with demo code

You can download the Demo code

Open the project with keil: Open429I-IT8951-Demo\Project\IT8951\MDK-ARM\Project.uvproj

Compile it, then open IT8951.h, check if I80 mode is enabled. Compile it again and download to your board.


Information are printed to serial port as below (115200, 8N1)


Display pictures

For easy porting our demo code, we display picture with data matrix instead of file system.

We should first convert BMP picture to data matrix (arrays), and use it in demo code.

1) Prepare a BMP image, resize the picture to 800*600

2) Open BMP convert software, Click File->Open..-> to open the picture as below:


3) Click Image -> Convert to ->Gray256(8 BPP)


4) Click File ->Save As... ->Choose "C" bitmap file (*.c) -> input file name and click Save.

5) Choose 8 bit per pixel, click OK. A C file will be saved to your PC


6) Add the C file to keil project, delect unusable information

*                SEGGER Microcontroller GmbH & Co. KG                *
*        Solutions for real time microcontroller applications        *
*                           www.segger.com                           *
*                                                                    *
* C-file generated by                                                *
*                                                                    *
*        Bitmap Converter for emWin V5.22.                           *
*        Compiled Jul  4 2013, 12:18:24                              *
*        (c) 1998 - 2013 Segger Microcontroller GmbH && Co. KG       *
*                                                                    *
*                                                                    *
* Source file: zoo_800_600                                           *
* Dimensions:  800 * 600                                             *
* NumColors:   256                                                   *
*                                                                    *
#include <stdlib.h>
#include "GUI.h"
  #define GUI_CONST_STORAGE const
extern GUI_CONST_STORAGE GUI_BITMAP bmzoo_800_600;
*       Palette
*  Description
*    The following are the entries of the palette table.
*    The entries are stored as a 32-bit values of which 24 bits are
*    actually used according to the following bit mask: 0xBBGGRR
*    The lower   8 bits represent the Red   component.
*    The middle  8 bits represent the Green component.
*    The highest 8 bits represent the Blue  component.
static GUI_CONST_STORAGE GUI_COLOR _Colorszoo_800_600[] = {
  0x000000, 0x010101, 0x020202, 0x030303,
  0x040404, 0x050505, 0x060606, 0x070707,
  0x080808, 0x090909, 0x0A0A0A, 0x0B0B0B,
  0x0C0C0C, 0x0D0D0D, 0x0E0E0E, 0x0F0F0F,
  0x101010, 0x111111, 0x121212, 0x131313,
  0x141414, 0x151515, 0x161616, 0x171717,
  0x181818, 0x191919, 0x1A1A1A, 0x1B1B1B,
  0x1C1C1C, 0x1D1D1D, 0x1E1E1E, 0x1F1F1F,
  0x202020, 0x212121, 0x222222, 0x232323,
  0x242424, 0x252525, 0x262626, 0x272727,
  0x282828, 0x292929, 0x2A2A2A, 0x2B2B2B,
  0x2C2C2C, 0x2D2D2D, 0x2E2E2E, 0x2F2F2F,
  0x303030, 0x313131, 0x323232, 0x333333,
  0x343434, 0x353535, 0x363636, 0x373737,
  0x383838, 0x393939, 0x3A3A3A, 0x3B3B3B,
  0x3C3C3C, 0x3D3D3D, 0x3E3E3E, 0x3F3F3F,
  0x404040, 0x414141, 0x424242, 0x434343,
  0x444444, 0x454545, 0x464646, 0x474747,
  0x484848, 0x494949, 0x4A4A4A, 0x4B4B4B,
  0x4C4C4C, 0x4D4D4D, 0x4E4E4E, 0x4F4F4F,
  0x505050, 0x515151, 0x525252, 0x535353,
  0x545454, 0x555555, 0x565656, 0x575757,
  0x585858, 0x595959, 0x5A5A5A, 0x5B5B5B,
  0x5C5C5C, 0x5D5D5D, 0x5E5E5E, 0x5F5F5F,
  0x606060, 0x616161, 0x626262, 0x636363,
  0x646464, 0x656565, 0x666666, 0x676767,
  0x686868, 0x696969, 0x6A6A6A, 0x6B6B6B,
  0x6C6C6C, 0x6D6D6D, 0x6E6E6E, 0x6F6F6F,
  0x707070, 0x717171, 0x727272, 0x737373,
  0x747474, 0x757575, 0x767676, 0x777777,
  0x787878, 0x797979, 0x7A7A7A, 0x7B7B7B,
  0x7C7C7C, 0x7D7D7D, 0x7E7E7E, 0x7F7F7F,
  0x808080, 0x818181, 0x828282, 0x838383,
  0x848484, 0x858585, 0x868686, 0x878787,
  0x888888, 0x898989, 0x8A8A8A, 0x8B8B8B,
  0x8C8C8C, 0x8D8D8D, 0x8E8E8E, 0x8F8F8F,
  0x909090, 0x919191, 0x929292, 0x939393,
  0x949494, 0x959595, 0x969696, 0x979797,
  0x989898, 0x999999, 0x9A9A9A, 0x9B9B9B,
  0x9C9C9C, 0x9D9D9D, 0x9E9E9E, 0x9F9F9F,
  0xA0A0A0, 0xA1A1A1, 0xA2A2A2, 0xA3A3A3,
  0xA4A4A4, 0xA5A5A5, 0xA6A6A6, 0xA7A7A7,
  0xA8A8A8, 0xA9A9A9, 0xAAAAAA, 0xABABAB,
  0xB0B0B0, 0xB1B1B1, 0xB2B2B2, 0xB3B3B3,
  0xB4B4B4, 0xB5B5B5, 0xB6B6B6, 0xB7B7B7,
  0xB8B8B8, 0xB9B9B9, 0xBABABA, 0xBBBBBB,
  0xC0C0C0, 0xC1C1C1, 0xC2C2C2, 0xC3C3C3,
  0xC4C4C4, 0xC5C5C5, 0xC6C6C6, 0xC7C7C7,
  0xC8C8C8, 0xC9C9C9, 0xCACACA, 0xCBCBCB,
  0xD0D0D0, 0xD1D1D1, 0xD2D2D2, 0xD3D3D3,
  0xD4D4D4, 0xD5D5D5, 0xD6D6D6, 0xD7D7D7,
  0xD8D8D8, 0xD9D9D9, 0xDADADA, 0xDBDBDB,
  0xE0E0E0, 0xE1E1E1, 0xE2E2E2, 0xE3E3E3,
  0xE4E4E4, 0xE5E5E5, 0xE6E6E6, 0xE7E7E7,
  0xE8E8E8, 0xE9E9E9, 0xEAEAEA, 0xEBEBEB,
  0xF0F0F0, 0xF1F1F1, 0xF2F2F2, 0xF3F3F3,
  0xF4F4F4, 0xF5F5F5, 0xF6F6F6, 0xF7F7F7,
  0xF8F8F8, 0xF9F9F9, 0xFAFAFA, 0xFBFBFB,
static GUI_CONST_STORAGE GUI_LOGPALETTE _Palzoo_800_600 = {
  256,  // Number of entries
  0,    // No transparency
  800, // xSize
  600, // ySize
  800, // BytesPerLine
  8, // BitsPerPixel
  _aczoo_800_600,  // Pointer to picture data (indices)
  &_Palzoo_800_600   // Pointer to palette

7) Modify the codes

static GUI_CONST_STORAGE unsigned char _aczoo_800_600[] = {

to this one. (You can change the name of the array to every one you like)

const unsigned char zoo_800_600[] = {

8) Modify related codes in IT8951.C as below

extern const unsigned char zoo_800_600[];
void IT8951DisplayExample3()
	IT8951LdImgInfo stLdImgInfo;
	IT8951AreaImgInfo stAreaImgInfo;
	TWord width = gstI80DevInfo.usPanelW;
	TWord high = gstI80DevInfo.usPanelH;
	TDWord i;
	for (i = 0;i < width*high;i++)
		gpFrameBuf[i] = zoo_800_600[i];
	//Setting Load image information
	stLdImgInfo.ulStartFBAddr    = (TDWord)gpFrameBuf;
	stLdImgInfo.usEndianType     = IT8951_LDIMG_L_ENDIAN;
	stLdImgInfo.usPixelFormat    = IT8951_8BPP; 
	stLdImgInfo.usRotate         = IT8951_ROTATE_0;
	stLdImgInfo.ulImgBufBaseAddr = gulImgBufAddr;
	//Set Load Area
	stAreaImgInfo.usX      = 0;
	stAreaImgInfo.usY      = 0;
	stAreaImgInfo.usWidth  = width;
	stAreaImgInfo.usHeight = high;
	IT8951HostAreaPackedPixelWrite(&stLdImgInfo, &stAreaImgInfo);//Display function 2
	IT8951DisplayArea(0,0, gstI80DevInfo.usPanelW, gstI80DevInfo.usPanelH, 2);

【Note】Guides provided here are all about how to use the 7.8inch e-Paper HAT (D). If you have any question about how to modify and develope you own codes, please refer to resources of IT8951 #Resources


Hardware Connection

For different ink screen models, due to product upgrades and improvements, there may be certain differences between the hardware connection and the picture, and the specific FPC line pin label shall prevail:

Check example 1:
Check example 1.png
Check example 2:
Check example 2.png

DIP switch

DIP switch.png

I2C interface driver is not recommended at present, it is recommended to use a USB, I80, or SPI interface driver

Whether it is driven by a USB interface, I80 interface, or SPI interface, it is necessary to turn the DIP switch circled in the red frame in the figure below to the ON position on the right, as shown in the figure below:

If the PC is connected by USB, and the E-LINK-TCON-DEMO cannot recognize the IT8951, please check whether both sides of the two DIP switches marked in the red frame are connected. Only the two DIP switches marked in the red frame are both connected. turn on to be recognized by the PC.

SPI or I80 driver.png

Choose SPI or I80 driver

If you use a USB drive, you don't need to pay attention to the DIP switch in the green frame shown in the figure below.
If you use SPI driver or I80 driver, you need to pay attention to the DIP switch in the green frame shown in the figure below. If it is dialed to the I80 terminal, it means that the I80 driver is used, and if it is dialed to the SPI terminal, it means that the SPI driver is used:

Codes Description

New Features

1. Update 16 grayscale images in 4bpp mode to reduce the data size while transmitting via SPI.
2. Double SPI transmitting speed. Note that this feature can only be valid in Raspberry Pi, it is invalid in Pi 4 because of the improvement of CPU.
3. Reduce the update time to 1/4. The last version of Demo codes cost 10s to update a picture on 10.3inch e-Paper (D) in GC16 Mode, with the new version, it is reduced to 3s.
4. Fix the bug that the memory leaks problem occurs after opening a BMP file.
5. Add 1bpp, 2bpp, 3bpp, and 4bpp modes support.
6. Add A2 Mode (only work for 1bpp mode)
7. Add GUI functions (Draw point, line, circle, rectangle, and string display). Supports changing gray.
8. Add 1bpp, 2bpp, 4bpp, and 8bpp refresh support for BMP pictures, if you choose 1bpp, it also supports A2 mode refresh.
9. Add a demo for displaying GIF pictures, which can write multiple pictures into the IT8951 cache, and directly swipe the data of different addresses in the cache into the ink screen for display, eliminating the data transmission process between RPi and IT8951, Refresh frame rate up to 7fps
10. Add fps testing, it can be used to test the fps when updated with different windows sizes in different modes.
11. Enhance the driver, to fix the bug of blurred display in the partial area.
12. Support bytes alignment for 6inch ePaper HAT and 6inch HD ePaper HAT in 1bpp mode.
13. Add VCOM setting and clear ePaper function (running Demo codes directly) to protect ePaper from damage.
14. Improving the structure of driver codes for higher code readability.

Examples Description

Display 16 bars in grayscale order

  • Function:DisplayColorPaletteExample
  • This function is sued to display 16 bars in different grayscale. It uses 4bpp in GC16 mode.


  • Function: DisplayCharacterPatternExample
  • This function is sued to draw point, line, circle, rectange as well as display string. It suppots 1bpp, 2bpp, 4bpp and 8bpp mode. If you use 1bpp, it can also supports the A2 update mode.

Display BMP image

  • Function:DisplayBMPExample
  • This function is used to display a BMP image. It suppots 1bpp, 2bpp, 4bpp and 8bpp mode. If you use 1bpp, it can also supports the A2 update mode.

Update ePaper in A2 mode

  • Function:DynamicRefreshExample
  • This function is used to update ePaper in A2 Mode.

Display GIF image

  • Function:DynamicGIFExample
  • This function is used to display GIF image. We divide a GIF file to seven BMP images, and save them to buffer of IT8951 with continuous address. This demo features the fastest fps of the ePaper (about 7fps).

FPS Testing

  • Function:CheckFrameRateExample
  • This function is sued to test fps in different modes. The demo will auot-caculate the update time of 10 frames and the fps.。

Related Description


The firmware in IT8951 Driver board are different among differnt types of e-Paper. And the update mode maybe different among these e-Paper. For more information abou the update modes, you can refer to IT8951 Mode Description. There are three modes: INIT, GC16 and A2.

Mode Description 6inch/6inch HD 7.8inch/9.7inch/10.3inch
INIT This mode is used for clearing the display. If you use A2 mode for updating, we recommend you use the INIT mode to clear display after updating several times. Mode0 Mode0
GC16 This mode is used for updating ePaper with 16 grayscale. GC16 mode can provide best dispaly effect. Mode2 Mode2
A2 A2 mode can only support 2 grayscale, however, the update speed is the fastest. Mode4 Mode6
//basic mode definition
UBYTE INIT_Mode = 0;
UBYTE GC16_Mode = 2;
//A2_Mode's value is not fixed, is decide by firmware's LUT 
UBYTE A2_Mode = 6;
if( strcmp(LUT_Version, "M641") == 0 ){
    //6inch e-Paper HAT(800,600), 6inch HD e-Paper HAT(1448,1072), 6inch HD touch e-Paper HAT(1448,1072)
    A2_Mode = 4;
    Four_Byte_Align = true;
}else if( strcmp(LUT_Version, "M841") == 0 ){
    //9.7inch e-Paper HAT(1200,825)
    A2_Mode = 6;
}else if( strcmp(LUT_Version, "M841_TFA2812") == 0 ){
    //7.8inch e-Paper HAT(1872,1404)
    A2_Mode = 6;
}else if( strcmp(LUT_Version, "M841_TFA5210") == 0 ){
    //10.3inch e-Paper HAT(1872,1404)
    A2_Mode = 6;
    //default set to 6 as A2 Mode
    A2_Mode = 6;


bpp(Bits Per Pixel), stands for the bits costed by every pixel. The current versions of ePaper support 1bpp, 2bpp, 4bpp, and 8bpp modes.

  • 1bpp
  • 1bit cost by every pixel
  • It supports 2 grayscale displays. supports A2 mode
  • Evey byte carries 8 pixels
  • The pixel is saved in byte in Big-endian format:
  • The data saved in IT8951 with Little-endian format, you need to convert data before saving.
  • 2bpp
  • 2bits cost by every pixel
  • Supports 4 (2^2=4) grayscale
  • Evey byte carries 4 pixels
  • The pixel is saved in byte in Big-endian format:
  • The data saved in IT8951 with Little-endian format, you need to convert data before saving.
  • 4bpp
  • 4bits cost by every pixel.
  • Supports 16(2^4=16) grayscale
  • Every byte carries 2 pixels
  • The pixel is saved in byte in Big-endian format:
  • The data saved in IT8951 with Little-endian format, you need to convert data before saving.
  • 4bpp mode is recommended for displaying 16 grayscale images. It reduces half of the data by comparing to 8bpp.
  • 8bpp
  • 8bits cost by every pixel
  • Supports 256 (2^8=256) grayscale. However, IT8951 only uses the first four bits for 16 grayscale displays.
  • Every byte carries one pixel
  • The pixel is saved in byte in Big-endian format:
  • The data saved in IT8951 with Little-endian format, you need to convert data before saving.
  • When you convert an original image for a gray image, the data of every pixel cost one byte (8 bits). You can compress the data according to the actual data format. For example: if you want to convert data for 2bpp mode, you can just use the first 2bits from on byte (original gray image). The examples below also convert the data format from big-endian to little-endian.
UDOUBLE Addr = X * (Paint.BitsPerPixel) / 8 + Y * Paint.WidthByte;
switch( Paint.BitsPerPixel ){
    case 8:{
        Paint.Image[Addr] = Color & 0xF0;
    case 4:{
        Paint.Image[Addr] &= ~( (0xF0) >> (7 - (X*4+3)%8 ) );
        Paint.Image[Addr] |= (Color & 0xF0) >> (7 - (X*4+3)%8 );
    case 2:{
        Paint.Image[Addr] &= ~( (0xC0) >> (7 - (X*2+1)%8 ) );
        Paint.Image[Addr] |= (Color & 0xC0) >> (7 - (X*2+1)%8 );
    case 1:{
        Paint.Image[Addr] &= ~( (0x80) >> (7 - X%8) );
        Paint.Image[Addr] |= (Color & 0x80) >> (7 - X%8);

4-byte alignment description

In the actual test, we found that for those 3 products: 6inch e-Paper HAT, 6inch HD e-Paper HAT, and 6inch HD touch e-Paper HAT, when refreshing in 1bpp mode, we need to make the starting point of the refresh area X and the refresh width W to perform 4-byte (32bit) alignment, otherwise, the image in the refresh area will display abnormally. The specific operation is shown in the following program:

if( strcmp(LUT_Version, "M641") == 0 ){
    //6inch e-Paper HAT(800,600), 6inch HD e-Paper HAT(1448,1072), 6inch HD touch e-Paper HAT(1448,1072)
    A2_Mode = 4;
    Four_Byte_Align = true;
}else if( strcmp(LUT_Version, "M841") == 0 ){
if(Four_Byte_Align == true){
    In_4bp_Refresh_Area_Width = Panel_Width - (Panel_Width % 32);
    In_4bp_Refresh_Area_Width = Panel_Width;
X_Start = Min_X < 32 ? 0 : Min_X - (Min_X % 32);
X_End = ( Max_X + (32 - (Max_X % 32)) ) > Touch_Pannel_Area_Width ? ( Max_X - (Max_X % 32) )  : ( Max_X + (32 - (Max_X % 32)) );
Y_Start = Min_Y;
Y_End = Max_Y;
Width = X_End - X_Start;
    Width = 32;
Height = Y_End-Y_Start;
    Height = 32;

SPI transmission speed description

Due to the difference in CPU frequency between Raspberry Pi 3 and Raspberry Pi 4:

  • Raspberry Pi 3 can still transmit normally when the frequency is divided by 16, but the frequency by 16 is the fastest speed for Pi3.
  • When the frequency of the Raspberry Pi 4B uses a divide by 16, the SPI rate is too high and transmission errors will occur. Therefore, the SPI of the Raspberry Pi 4B can only use a divide by 32 at the fastest.
  • In the BCM2835 library manual, for different Raspberry Pi versions and different clock divisions, the corresponding frequency description is shown in the following figure:


  • If you need to obtain the most suitable SPI transmission speed, you need to select a different SPI clock divider according to your Raspberry Pi version, as shown in the following program and its notes:
bcm2835_spi_begin();//Start spi interface, set spi pin for the reuse function
bcm2835_spi_setBitOrder(BCM2835_SPI_BIT_ORDER_MSBFIRST);//High first transmission
bcm2835_spi_setDataMode(BCM2835_SPI_MODE0);//spi mode 0
//bcm2835_spi_setClockDivider(BCM2835_SPI_CLOCK_DIVIDER_16);//For RPi 3/3B/3B+
bcm2835_spi_setClockDivider(BCM2835_SPI_CLOCK_DIVIDER_32);//For RPi 4B
/* SPI clock reference link:*/

Enhance driving capability

In some cases, due to the long FPC cable and other reasons, the ink screen display will be partially blurred. In this case, you can try to increase the driving capability to effectively solve the problem of the screen display blur.

You can check the demo as below:

    Debug("Attention! Enhanced driving ability, only used when the screen is blurred\r\n");
function :  Enhanced driving capability
parameter:  Enhanced driving capability for IT8951, in case the blurred display effect
void Enhance_Driving_Capability(void)
    UWORD RegValue = EPD_IT8951_ReadReg(0x0038);
    Debug("The reg value before writing is %x\r\n", RegValue);
    EPD_IT8951_WriteReg(0x0038, 0x0602);
    RegValue = EPD_IT8951_ReadReg(0x0038);
    Debug("The reg value after writing is %x\r\n", RegValue);

If you use the E-LINK-TCON-DEMO software on a PC (Windows) to refresh the ink screen through the USB interface, you can modify the register value in the following ways to enhance the drive capability:

  • Step1: Read the data of register address 0x18000038.

13.3inch epaper 01.png

If the read data of register address 0x18000038 is 0x02, it means that the drive capability has not been enhanced yet.

  • Step2: Modify the data of register address 0x18000038

13.3inch epaper 02.png

Modify the data of register address 0x18000038 to 602 to enhance the driving capability.

  • Step3: Check the data of register address 0x18000038.

13.3inch epaper 03.png

Check whether the data of the register address 0x18000038 is modified successfully. If the data of this address is 0x602, it means that the drive capacity has been enhanced.

Use the correct VCOM value

The VCOM value of each model of the e-paper is marked on the FPC cable. Make sure that you have used the correct VCOM value when you running the demo. Otherwise, the e-paper will deteriorate by working for a long time under the wrong VCOM value.



Demo code




The most likely reason for not being able to print the picture is that the wires are not connected correctly. Please check the wiring. Due to the different batches of products, the wiring method may not be exactly the same as the picture. Please refer to the cable and 1 and 40 on the silk screen. As shown in the red line in the figure below:




1. Replace the Micro USB cable with good quality. There are many USB cables on the market that have too much voltage drop, which will cause the USB interface to fail to enumerate normally.

2. Try changing the USB interface. It is recommended to use the USB interface on the back of the PC. Relatively speaking, the power supply current will be larger.
3. Turn the DIP switch to the end. During shipping, the DIP switches may be loosened, and the floating configuration pins cannot put the IT8951 into USB mode.



Click connect. The following information will be displayed normally (different models will display different information):

If you fail to refresh, check whether the hard link is normal, use the USB port on the back of the PC (most of the USB ports on the front of the PC have weak power supply capability), and replace the e-paper test. Note: Do not plug and unplug the e-paper with power on, otherwise the driver board and e-paper may be damaged.




If you require technical support, please go to the Support page and open a ticket.