7.8inch e-Paper HAT

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7.8inch e-Paper raw Panel
7.8inch-e-Paper-4.jpg

1872 × 1404, 7.8inch EPD panel without driver board
7.8inch e-paper HAT
7.8inch-e-Paper-HAT-4.jpg

1872 × 1404, 7.8inch EPD HAT for Raspberry Pi, USB/SPI/I80/I2C interface
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7.8inch e-Paper is big size screen, the glass panel and FPC is fragile, please be careful when use it for developing. we recommend you to reinforce the FPC with scotch tape when developing. Please connect all the cables before powering the device, the device cannot support hot-plug.

There are two version, one is raw panel and another is HAT version. Driver board (IT8951) is required for raw panel, if you are the first time to buy this e-paper, recommend you to choose HAT version which come with the driver board.

Introduction

  • 7.8inch EPD (Electronic Paper Display) HAT for Raspberry Pi, 1872 x 1404 resolution, 16 gray scale, USB/SPI/I80/I2C interface
  • It has the advantages of low power consumption, wide viewing angle, and clear display under direct sunlight, and is often used in display applications such as shelf labels and industrial instruments.
More

Features

  • No backlight, keeps displaying last content for a long time even when power down
  • Low power consumption, basically power is only required for refreshing
  • Compatible with Raspberry Pi Zero/Zero W/Zero WH/2B/3B/3B+
  • 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)

Specifications

  • Operating voltage: 5V
  • Interface: USB/SPI/I80/I2C
  • Outline dimension: 173.8mm × 127.6mm × 0.78mm
  • Display size: 158.184mm × 118.638mm
  • Dot pitch: 0.0845mm × 0.0845mm
  • 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 7.8inch e-paper to IT8951 driver board as below

7.8inch-e-Paper-HAT-1.jpg

  • Connect USB interface of IT8951 driver board to PC, then connect PWR ONLY interface of IT8951 to 5V power adapter.
The refresh consumption of e-Paper is high, therefore, external power supply is required. You must first connect data cable then the power, otherwise, e-Paper cannot be recognized properly.

10.3inch-e-Paper-HAT-D-Manual-02.jpg

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

10.3inch-e-Paper-HAT-D-Manual-03.jpg

  • Click "display" to refresh the picture

10.3inch-e-Paper-HAT-D-Manual-04.jpg

Working with Raspberry Pi

  • Hardware connection
Insert IT8951 driver board to GPIO of Raspberry Pi, Connect e-Paper to driver board
7.8inch-e-Paper-HAT-Manual-02.jpg
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
MISO P9 MISO Pin of SPI
MOSI P10 MOSI Pin of SPI
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)
  • Make sure you have switched the sail switch to SPI mode
9.7inch-e-Paper-HAT-Manual-14.jpg
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 with the commands below. You can also follow the instruction on its website above
tar zxvf bcm2835-1.xx.tar.gz
cd bcm2835-1.xx
./configure
make
sudo make check
sudo make install
  • Download Demo codes of 10.3inch e-Paper HAT and test
git clone https://github.com/waveshare/IT8951-ePaper.git
cd IT8951-ePaper/Raspberry
sudo make clean
sudo make -j4
  • Check the VCOM value on the FPC
6inch-HD-e-Paper-HAT-Manual-06.png

Add the VCOM value as paramter and test the e-Paper, and this model is mode 0.

sudo ./epd -2.51 0
  • Demo execution phenomenon:

1) First, the r-paper will refresh the 16 gray bars partially in sequence.

2) Then demonstrate the demo of drawing lines, circles, rectangles, characters, and numbers

3) Then respectively demonstrate the demo of displaying BMP pictures in 1bp, 2bp, and 4bp modes

4) Next, demonstrate the effect of fast refresh in A2 mode

5) Then display a gif animation

6) Then demonstrate a Demo that counts the frame rate

7) Finally, the e-paper is whitened in Init mode for long-term storage.

Working with STM32

Because IT8951 will cost big size of RAM, some of STM32 cannot support without external SDRAM device. So we here use Open429I as test board, Open429I integrates IS42S16400J (64-MBIT) SDRAM,has full memory to drive the 9.7inch e-paper.

Working with STM32, you can use SPI, I80 or I2C interface. SPI is simple and only a few of GPIOs are used, its speed can also meet the requirement of most applications. I80 is also simple and fast, however, it need to use lots of GPIO. I2C is every slow, which we don't recommend.

SPI


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

9.7inch-e-Paper-HAT-Manual-14.jpg

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.

9.7inch-e-Paper-HAT-Manual-15.jpg

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

10.3inch-e-Paper-HAT-D-Manual-09.jpg

I80


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

9.7inch-e-Paper-HAT-Manual-17.jpg

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.

9.7inch-e-Paper-HAT-Manual-18.jpg

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

10.3inch-e-Paper-HAT-D-Manual-10.jpg

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:

10.3inch-e-Paper-HAT-D-Manual-11.jpg

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

10.3inch-e-Paper-HAT-D-Manual-12.jpg

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

9.7inch-e-Paper-HAT-Manual-21.jpg

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"
 
#ifndef GUI_CONST_STORAGE
  #define GUI_CONST_STORAGE const
#endif
 
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,
  0xACACAC, 0xADADAD, 0xAEAEAE, 0xAFAFAF,
  0xB0B0B0, 0xB1B1B1, 0xB2B2B2, 0xB3B3B3,
  0xB4B4B4, 0xB5B5B5, 0xB6B6B6, 0xB7B7B7,
  0xB8B8B8, 0xB9B9B9, 0xBABABA, 0xBBBBBB,
  0xBCBCBC, 0xBDBDBD, 0xBEBEBE, 0xBFBFBF,
  0xC0C0C0, 0xC1C1C1, 0xC2C2C2, 0xC3C3C3,
  0xC4C4C4, 0xC5C5C5, 0xC6C6C6, 0xC7C7C7,
  0xC8C8C8, 0xC9C9C9, 0xCACACA, 0xCBCBCB,
  0xCCCCCC, 0xCDCDCD, 0xCECECE, 0xCFCFCF,
  0xD0D0D0, 0xD1D1D1, 0xD2D2D2, 0xD3D3D3,
  0xD4D4D4, 0xD5D5D5, 0xD6D6D6, 0xD7D7D7,
  0xD8D8D8, 0xD9D9D9, 0xDADADA, 0xDBDBDB,
  0xDCDCDC, 0xDDDDDD, 0xDEDEDE, 0xDFDFDF,
  0xE0E0E0, 0xE1E1E1, 0xE2E2E2, 0xE3E3E3,
  0xE4E4E4, 0xE5E5E5, 0xE6E6E6, 0xE7E7E7,
  0xE8E8E8, 0xE9E9E9, 0xEAEAEA, 0xEBEBEB,
  0xECECEC, 0xEDEDED, 0xEEEEEE, 0xEFEFEF,
  0xF0F0F0, 0xF1F1F1, 0xF2F2F2, 0xF3F3F3,
  0xF4F4F4, 0xF5F5F5, 0xF6F6F6, 0xF7F7F7,
  0xF8F8F8, 0xF9F9F9, 0xFAFAFA, 0xFBFBFB,
  0xFCFCFC, 0xFDFDFD, 0xFEFEFE, 0xFFFFFF
};
 
static GUI_CONST_STORAGE GUI_LOGPALETTE _Palzoo_800_600 = {
  256,  // Number of entries
  0,    // No transparency
  &_Colorszoo_800_600[0]
};
 
GUI_CONST_STORAGE GUI_BITMAP bmzoo_800_600 = {
  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];
	}
 
	IT8951WaitForDisplayReady();
 
	//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 10.3inch 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

FAQ

 Answer:
*refresh mode
    • Full brush: The electronic ink screen will flicker several times during the refresh process (the number of flickers depends on the refresh time), and the flicker is to remove the afterimage to achieve the best display effect
    • Bureau brush: The electronic ink screen has no flickering effect during the refresh process. Users who use the partial brushing function note that after refreshing several times, a full brush operation should be performed to remove the residual image, otherwise the residual image problem will become more and more serious, or even damage the screen (currently only some black and white e-ink screens support partial brushing, please refer to product page description)
  • refresh rate
    • During use, it is recommended that customers set the refresh interval of the e-ink screen to at least 180 seconds (except products that support the local brush function)
    • During the standby process (that is, after the refresh operation), it is recommended that the customer set the e-ink screen to sleep mode, or power off operation (the power supply part of the ink screen can be disconnected with an analog switch) to reduce power consumption and prolong the life of the e-ink screen. (If some e-ink screens are powered on for a long time, the screen will be damaged beyond repair.)
    • During the use of the three-color e-ink screen, it is recommended that customers update the display screen at least once every 24 hours (if the screen remains the same screen for a long time, the screen burn will be difficult to repair)
  • place of use
    • The e-ink screen is recommended for indoor use. If you use it outdoors, you need to avoid direct sunlight on the e-ink screen, and take UV protection measures at the same time. When designing e-ink screen products, customers should pay attention to determine whether the use environment meets the temperature and humidity requirements of the e-ink screen
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 Answer:
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:

Faqe-link.png

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 Answer:
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.

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

Connect.png
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.

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Resources

Schematic

Demo code

Datasheet

Other documents

Software

Supports