13.3inch e-Paper HAT+ (E) Manual

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1.3inch e-Paper HAT+ (E)
Raw display, without driver board
13.3inch e-Paper (E)

1600×1200, RPi/SPI, E6 Full Color e-Paper
1.3inch e-Paper HAT+ (E)
With e-Paper Driver HAT
13.3inch e-Paper HAT+ (E)

1600×1200, RPi/SPI, E6 Full Color e-Paper
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Overview

Parameters

Size 13.3inch
Driver Board Size 65.00mm × 30.50mm
Display Size 270.40mm × 202.80mm
Outline Dimensions 284.70mm × 208.80mm × 0.85mm
Operating Voltage 3.3V / 5V (IO level voltage should be the same as the supply voltage)
Communication Interface SPI
Dot Pitch 0.169mm × 0.169mm
Resolution 1600 × 1200
Display Color E6 Full Color
Grayscale 2
Refresh Time 19s
Total Refresh Power <0.5W(typ.)
Operating Temperature 0 ~ 40 ℃
Storage Temperature -25 ~ 60 ℃
  • Refresh time: The refresh time is based on experimental test data, and there may be errors in the actual refresh time. The actual results shall prevail. There will be a flickering effect during the global refresh process, which is a normal phenomenon.
  • Refresh power consumption: The power consumption data is experimental test data, and the actual power consumption may have certain errors due to the presence of the driver board and actual usage. The actual results shall prevail.
  • Refresh at low temperatures may cause a color cast, and it is necessary to stand still at 25°C for 6 hours before refreshing.

Communication Method

4.37inch-e-paper-manual-2.jpg

  • CSB (CS): Slave chip selection signal, low active. When CS is low level, the chip is enabled.
  • SCL (SCK/SCLK): Serial clock signal.
  • D/C (DC): Data/Command control signal, writes commands at a low level; writes data/parameter at a high level.
  • SDA (DIN): Serial data signal.
  • Timing sequence: CPHL=0, CPOL=0 (that is, SPI mode 0).
Note: For specific information about SPI communication, you can search for information online.

Working Principle

  • This product is an e-Paper device adopting the image display technology of Microencapsulated Electrophoretic Display, MED. The basic principle is that the charged nanoparticles suspended in the liquid are subjected to the electric field to produce migration. 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 almost 180 degrees. It is the ideal choice for e-reading.

Programming Principle

  • For a computer, images are composed of pixels, and the amount of space each pixel occupies determines the number of possible states (colors) it can have. The simplest black and white images have each pixel occupy one bit (1Bit), being either 0 or 1, black or white. As the number of colors increases, each pixel requires more space, such as eight bits, sixteen bits, twenty-four bits, and so on
  • This module uses a non-standard 24-bit image. If you need to create your own images, you can refer to the "Picture processing" section.
  • For black and white images, we can define it as 0 if it is black and 1 if it is white, so there is a way to represent colors:
    • White: □, corresponding to 1
    • Black: ■, corresponding to 0
  • A dot is generally called a pixel on the graph, and the color is either 1 or 0, that is, 1 bit can identify the color: 1Pixel = 1bit, then a byte contains 8 pixels.
  • Take 16 pixels as an example. We assume that the first 8 pixels are black and the last 8 pixels are white. Then it can be thought that pixels 1-16 correspond to bits 0 to 15, and 0 means black. 1 means white:

E-paper hardware work 1.png

  • For the computer, the way it stores data is that the high bits come first and the low bits come last, and each byte only has 8 bits, so there may be a slight change:

E-paper hardware work 2.png

  • In this way, only 2 bytes are required to represent 16 pixels.
  • Now suppose we have six colors, so we need at least three digits of data to represent all colors, but in order to facilitate the operation, we add a 0 in front of it, that is, use four digits of data to represent the color of a pixel, so that one byte (1Byte) can represent two pixels. Actually, the controller of this module uses this method.
Color BIN HEX The color (reference)
Black 0b0000 0x0
White 0b0001 0x1
Yellow 0b0010 0x2
Red 0b0011 0x3
Blue 0b0101 0x5
Green 0b0110 0x6
  • Taking four pixel points as an example, we assume that the colors of these four points are yellow, blue, red, and green respectively. Based on the table above, the human logic is as follows, storing them in sequence:
Pixel 1 2 3 4
Bit 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
Data 0 0 1 0 0 1 0 1 0 0 1 1 0 1 1 0
Color
  • For the computer, the way it stores data is that the high bits come first and the low bits come last, and each byte only has 8 bits,so it is stored in bytes like this:
Pixel 1 2 3 4
Bit 7 6 5 4 3 3 1 0 7 6 5 4 3 2 1 0
Data 0 0 1 0 0 1 0 1 0 0 1 1 0 1 1 0
Color
Byte 0x25 0x36

Double-IC Programming Analysis

The 13.3inch e-Paper (E) is a dual-IC controlled e-Paper screen, in addition to the above programming principle, please note the following
13.3inch-e-Paper-E-IC.jpg

  • As shown in the figure above, each IC controls half of the screen, and the two CS pins are used to control the corresponding M area (master area) and S area (slave area)
  • Except for CS pins, other control pins are shared
  • Except for common commands (initialization command and refresh command in the demo), only one CS pin is allowed to be pulled low at a time
  • When transmitting images, it should be noted that the display direction of the screen is horizontal display (X-axis direction), and after reaching the end point of a region, it will be displayed in the next line. Therefore, it is necessary to cut the picture into two pictures and transmit them separately, otherwise it will be displayed misalignment

Precautions

  1. Note that the screen cannot be powered on for a long time. When the screen does not refresh, the screen must be set to sleep mode or power off. Otherwise, the screen will remain in a high voltage state for a long time, which will damage the diaphragm and cannot be repaired.
  2. When using the e-paper screen, it is recommended that the refresh interval is at least 180s, and refreshed at least every 24 hours. If the e-paper screen is not used for a long time, it should be whitened and stored. (Refer to the data sheet for specific storage environment requirements)
  3. After the screen enters sleep mode, the image data sent will be ignored, and it can only be refreshed normally after re-initialization.
  4. If you find that the data of the created image is displayed incorrectly on the screen, it is recommended to check whether the image size is set correctly, and try again by changing the width and height settings.
  5. The working voltage requirement for an ink screen is 3.3V. If you purchase a raw display and need to work in a 5V environment when designing the circuit, it is recommended to perform level conversion processing.
  6. The FPC cable of the screen is relatively fragile. Please note: do not bend the cable in the vertical direction of the screen to avoid the cable being torn; do not repeatedly bend the cable excessively to avoid the cable breaking; do not bend the cable toward the front of the screen to prevent the cable from being disconnected from the panel. During debugging and R&D, it is recommended to fix the wiring before use.
  7. The ink screen screen is relatively fragile, so be careful to avoid falling, colliding, or pressing hard.
  8. We recommend that customers first use the sample demo we provide and use the corresponding development board to test after getting the screen.


Picture processing

Picture production and conversion of multi-color e-Paper

Picture production

Preparation

Software required: Adobe PhotoShop CC, Paint

Introduction

  • The Floyd-Steinberg dithering algorithm is ideal for displaying rich layers with a small number of colors. This allows for more color combinations and better shadow rendering of the original image. It is especially suitable for various use scenarios of e-Paper screens.
  • Here's how to convert a normal image into a Floyd-Steinberg scatter chart.
  • If you are interested in the actual algorithm, you can learn about our algorithm porting in ESP32 and ESP8266. Here, no further elaboration will be given.

Operation steps

Preparation: Download color table to your PC, and extract it to get the following files, we need to use N-color.act or 4-color.act, 6-color.act.
NcolorImageConvert 1.jpg

1. Create a new Photoshop project, set the width and height according to the actual resolution of the e-Papre screen, and use RGB color in the color mode. If the screen resolution used is 800*480, change the width to 800 pixels and the height to 480 pixels.
Color3.png

2. Prepare the corresponding materials, copy them into the project, and adjust parameters such as size and contrast (similar to the steps involved in general Photoshop image processing).
Pica.png

3. Select File - Store in the format used for the web and device.
Pica5.png

4. Select Load color table as shown below. Load the color table provided in the Preparation section.
Pica6.png

5. For seven-color pictures, load N-color.act, then click Save to save as a gif file. It is then converted to BMP format for use on this module.
For four-color pictures, load 4-color.act, then click Save to save as a gif file. It is then converted to BMP format for use on this module.
For six-color pictures, load 6-color.act, then click Save to save as a gif file. It is then converted to BMP format for use on this module.
Pica4.png

6. Open the GIF file with Paint, save it as a 24-bit BMP picture.
Pica7.png

7. At this point, the picture has been made, and it can be used in the TF card of the Raspberry Pi or e-Paper Shield module, or converted into an array for other embedded devices according to the next section.

Picture data conversion

Download demos

Note: This application is provided for your convenience and is open source, and our company does not provide technical support for it

Bug resolution

If your computer is win10/win11 and you do not have VS (Microsoft Visual Studio) or other Microsoft development tools installed, you may encounter error prompts: "ucrtbased.dll" and "vcruntime 140d.dll".
This means that these two components are missing from your computer, and the solution is as follows:
1. Install VS (Microsoft Visual Studio) or other Microsoft development tools (Visual C++ Redistributable, etc.).
2. Use the two component files provided by us
2.36inch e-paper picture make07.jpg
Put these two files in the directory C:\Windows\System32 and restart your computer

Conversion steps

  • Put the produced picture and the corresponding exe application in the same folder, you can put multiple pictures at the same time.
  • Drag and drop the picture onto the exe file, and the demo will convert the picture into a fixed name. c file.
  • Double-click on the cmd file, and the demo will convert all the pictures in the folder that match the size into a .c file with the corresponding names.
  • Four-color single picture demonstration (click on the picture to view the demonstration)

2.36inch e-paper picture make.gif

  • Four-color multi-picture demonstration (click on the picture to view the demonstration)

2.36inch e-paper picture make2.gif

  • Seven-color single picture demonstration (click on the picture to view the demonstration)

2.36inch e-paper picture make3.gif

  • Seven-color multi-picture demonstration (click on the picture to view the demonstration)

2.36inch e-paper picture make4.gif


Raspberry Pi

Hardware connection

When connecting to the Raspberry Pi, you can directly plug the board into the 40PIN pin header of the Raspberry Pi, and be careful to align the pins.
If you choose to use an 10PIN cable to connect, please refer to the pin corresponding table below:

Raspberry Pi connection pin correspondence
e-Paper Raspberry Pi
BCM2835 encoding Board physical pin number
VCC 3.3V 3.3V
GND GND GND
DIN MOSI 19
CLK SCLK 23
CS_M CE0 24
CS_S CE1 26
DC 25 22
RST 17 11
BUSY 24 18
PWR 18 12

Raspberry Pi Preparation

Disable SPI interface

  • Open the Raspberry Pi terminal and enter the following command to enter the configuration interface:
sudo raspi-config
Select Interface Options -> SPI -> Yes to disable the SPI interface

12.48-epaper-SPI-1.jpg 12.48-epaper-SPI-2.jpg 12.48-epaper-SPI-3.jpg

  • Restart Raspberry Pi:
sudo reboot

config.txt file setting

Use the command

sudo nano /boot/config.txt

or

sudo nano /boot/firmware/config.txt

Open the corresponding config.txt file
Add at the end

gpio=7=op,dl
gpio=8=op,dl

Press Ctrl+O (letter O) to save
Press Ctrl+X to exit

  • Restart Raspberry Pi:
sudo reboot

Run C demo

  • Install BCM2835 (Pi4, zero series, etc.)
#Open the Raspberry Pi terminal and run the following commands:
wget http://www.airspayce.com/mikem/bcm2835/bcm2835-1.71.tar.gz
tar zxvf bcm2835-1.71.tar.gz 
cd bcm2835-1.71/
sudo ./configure && sudo make && sudo make check && sudo make install
# For more information, please refer to the official website: http://www.airspayce.com/mikem/bcm2835/
  • Install wiringPi (Pi5)
git clone https://github.com/WiringPi/WiringPi
cd WiringPi
./build
gpio -v
# Run gpio -v and corresponding version will appear. If it does not appear, there is an installation error.
  • Download the demo (you can skip it if you have already downloaded it)
https://files.waveshare.com/wiki/13.3inch%20e-Paper%20HAT%2B/13.3inch_e-Paper_E.zip
unzip 4inch_e-Paper_E.zip -d 13.3inch_e-Paper_E
cd 13.3inch_e-Paper_E/RaspberryPi/
  • Alternate decompression method
sudo apt-get install p7zip-full
7z x 13.3inch_e-Paper_E.zip -O./13.3inch_e-Paper_E
cd 13.3inch_e-Paper_E/RaspberryPi/
  • Download the demo via GitHub (alternative method, skip if already downloaded)

Currently, accessing GitHub is not very smooth. It is recommended to use the above method to download from our official website.

git clone https://github.com/waveshare/e-Paper.git
cd e-Paper/E-paper_Separate_Program/13.3inch_e-Paper_E/RaspberryPi/
  • Compiler program (Note: -j4 means using 4 threads for compilation, the number can be modified by yourself)
# It is now in 13.3inch_e-Paper_E/RaspberryPi_JetsonNano
cd c
sudo make clean
# Use the BCM library to drive the Pi4
sudo make -j4 USELIB=USE_BCM2835_LIB
# Use the wiringPi library to drive the Pi5
sudo make -j4 USELIB=USE_WIRINGPI_LIB 
  • Run demo
sudo ./epd

Run python demo

  • Install function library
sudo apt-get update
sudo apt-get install python3-pip
sudo apt-get install python3-pil
sudo apt-get install python3-numpy
sudo apt-get install python3-spidev
  • Install function library (python2)
sudo apt-get update
sudo apt-get install python-pip
sudo apt-get install python-pil
sudo apt-get install python-numpy
sudo apt-get install python-spidev
  • Download the demo (you can skip it if you have already downloaded it)
https://files.waveshare.com/wiki/13.3inch%20e-Paper%20HAT%2B/13.3inch_e-Paper_E.zip
unzip 4inch_e-Paper_E.zip -d 13.3inch_e-Paper_E
cd 13.3inch_e-Paper_E/RaspberryPi/
  • Alternate decompression method
sudo apt-get install p7zip-full
7z x 13.3inch_e-Paper_E.zip -O./13.3inch_e-Paper_E
cd 13.3inch_e-Paper_E/RaspberryPi/
  • Download the demo via GitHub (alternative method, skip if already downloaded)

Currently, accessing GitHub is not very smooth. It is recommended to use the above method to download from our official website.

git clone https://github.com/waveshare/e-Paper.git
cd e-Paper/E-paper_Separate_Program/13.3inch_e-Paper_E/RaspberryPi/
  • Run demo
# Make sure it is in 13.3inch_e-Paper_E/RaspberryPi/
cd python/examples/
python3 epd_13in3e_test.py


Arduino

Hardware connection

Use an 10PIN cable to connect, please refer to the pin corresponding table below:

Arduino connection pin correspondence
e-Paper Arduino UNO Mega2560
VCC 5V 5V
GND GND GND
DIN D11 D51
CLK D13 D52
CS_M D10 D10
CS_S D9 D9
DC D8 D8
RST D7 D7
BUSY D6 D6
PWR D5 D5

Install IDE

Arduino IDE Windows Installation Tutorial

Run demo

  • In the data interface download the Demo, then unzip it and enter the 13.3inch_e-Paper_E directory to see the following content

E-paper arduino cede-R4-2.jpg

  • Open the demo: 13.3inch_e-Paper_E\Arduino_R4\Arduino_R4.ino

E-paper arduino cede-R4-3.jpg

  • In the Arduino IDE, select the corresponding development board (Board) and port (Port) in the Tools menu

E-paper arduino cede-R4-1.jpg

  • Finally, click Upload, and the upload is as follows (Arduino 1.8.13)

E-paper arduino cede3.jpg

STM32

Hardware connection

Use an 9PIN cable to connect, please refer to the pin corresponding table below:

STM32 connection pin correspondence
e-Paper STM32
VCC 3.3V
GND GND
DIN PA7
CLK PA5
CS_M PA4
CS_S PC4
DC PA2
RST PA1
BUSY PA3
PWR PA6

Run demo

  • Click to download the Demo, then unzip it and enter the 13.3inch_e-Paper_E directory to see the following content

E-paper stm32 cede1 f103zet6.jpg

  • Use Keil to open epd-demo.uvprojx in the 13.3inch_e-Paper_E\STM32-F103ZET6\MDK-ARM directory
  • Open Keil's compilation toolbar (which is generally open) < br/>

E-paper stm32 cede1.jpg

  • Click Compile

E-paper stm32 cede3.jpg

  • Make sure the appropriate programmer is connected, then click LOAD to download the demo to the microcontroller

ESP32

Hardware connection

STM32 connection pin correspondence
e-Paper ESP32
VCC 3.3V
GND GND
DIN IO14
CLK IO13
CS_M IO15
CS_S IO2
DC IO27
RST IO26
BUSY IO25
PWR IO33

Environment configuration

Online installation requires the use of VPN software, please click the link below for more information.

Run demo

  • In the data interface download the Demo, then unzip it and enter the 13.3inch_e-Paper_E directory to see the following content

Epd esp32-1.jpg

  • Open the demo: 13.3inch_e-Paper_E\ESP32\ESP32.ino

Epd esp32-2.jpg

  • In the Arduino IDE, select the corresponding development board (Board) and port (Port) in the Tools menu

Epd esp32-3.jpg

  • Finally, click Upload, and the upload is as follows (Arduino 2.2.1)

Epd esp32-4.jpg

FAQ

Software issues

 Answer:
  • Enter command: ls /dev/spi*
  • The result may appear as shown in the figure RPI FAQ 1.jpg
  • This is because the SPI interface is occupied in the /boot/config.txt file RPI FAQ 2.jpg
  • The solution is as follows:
    • Remove the occupation of spi0-0 in the /boot/config.txt file
    • Modify the position of the image in the /e-Paper/RaspberryPi_JetsonNano/lib/waveshare_epd/epdconfig.py file to 0,1
    • RPI FAQ 3.jpg


 Answer:
  • Our example demo uses STM32f103ZET6, if the customer modifies to other model in the MDK, such as STM32F103RBT6, the RAM space becomes smaller, and you need to modify the stack size and heap size in the startup file on the original basis.


 Answer:
  • When transmitting B/W data, use Data Start Transmission 1; When transmitting RED data, use Data Start Transmission 2.


 Answer:
  • The Chinese font library of our example demo uses GB2312 encoding. Please change your xxx_test.c file to GB2312 encoding format, compile and download it, and it will display normally.


 Answer:
  • The border display color can be set through the Border Waveform Control register or the VCOM AND DATA INTERVAL SETTING register.


 Answer:
  • In this case, the customer needs to reduce the number of refreshing positions and perform a screen clearing after refreshing 5 times.


 Answer:
  • The process of waking up the e-Paper is actually a process of re-powering on, so when the EPD wakes up, it needs to perform a screen clearing action first to minimize residual images.


 Answer:
  • May be caused by SPI driver failure:
    • 1. First check if the wiring is correct.
    • 2. Check if SPI is enabled and if the parameters are configured correctly. (Baud rate, mode and other parameters)


 Answer:
  • When switching from partial refresh to full refresh on the e-Paper, a full refresh initialization function needs to be added.


 Answer:
  • It may be that a C language demo based on the BCM2835 library has been run before. At this time, you need to restart the Raspberry Pi and then run the python demo.


 Answer:
  • Use the command "sudo apt-get install python-imaging" to install the imaging function library.


Hardware issues

 Answer:
  • Yes, there is now a level translation chip onboard that supports 5V drive.


 Answer:
  • The rated input voltage of the e-Paper is 2.3~3.6V. If it is a 5V system, level conversion is required. In addition, the voltage should not be lower than 2.5V to avoid affecting the display effect of the e-Paper.
  • For device selection, you can use the model in the schematic diagram we provide or select according to the data sheet.


 Answer:
  • Yes, please note that the timing needs to be correct.


 Answer:
  • Confirm if SPI communication is normal.
  • Confirm if the BUSY pin is properly initialized to input mode.
  • It may be that there is no normal reset. Try to shorten the duration of the low level during the reset. (Due to the addition of a power-off switch in the driver circuit, resetting the low level for too long can cause the driver board to lose power and result in reset failure.)
  • If the busy function has a send 0x71 command, you can try to comment it out.


 Answer:
  • 1.64 inch, 2.36 inch, 3 inch, 0.5mm pitch, 26pin
  • 1.02inch, 0.5mm pitch, 30pin
  • 4.37inch, 7.3inch, 0.5mm pitch, 50pin
  • The rest (non-parallel port) are 0.5mm pitch, 24pin


 Answer:
  • Cable socket 0.5-XXpin rear flip 2.0H (FPC connector).


Screen issues

 Answer:
  • [Working conditions] Temperature range: 0~40°C (the seven-color screen is: 15~35°C); humidity range: 35%~65%RH.
  • [Storage conditions]: Temperature range: below 30°C; Humidity range: below 55%RH; Maximum storage time: 6 months.
  • [Transportation conditions]: temperature range: -25~50°C; Maximum shipping time: 10 days.
  • [After unpacking]: Temperature range: 20°C±5°C; Humidity range: 50±5%RH; Maximum storage time: Complete assembly within 72 hours.


 Answer:
  • Refresh mode:
    • Full refresh: The e-Paper will flash multiple times during the refresh process (the number of flashes depends on the refresh time). The flashing is to remove residual images to achieve the best display effect.
    • Partial refresh: The e-Paper screen has no flickering effect during the refresh process. Users who use the partial refresh function should pay attention to performing a "full refresh" operation to clear the residual images after refreshing several times. Otherwise, the residual image problem will become more and more serious and even damage the screen. (Currently, only some black and white e-Paper screens support partial refresh, please refer to the product page description for details.)
  • Refresh frequency:
    • During use, it is recommended that customers set the refresh interval of the e-Paper screen to at least 180 seconds. (Except for products that support partial refresh function)
    • During the standby process (that is, after the refresh operation), it is recommended that customers set the e-Paper screen to sleep mode or power off (the power supply of the e-Paper can be disconnected with an analog switch) to reduce power consumption and extend the life of the e-Paper screen. (If some e-ink screens are powered on for a long time, the screen may be damaged and cannot be repaired.)
    • During the use of multi-color e-Paper screen, it is recommended that customers update the display screen at least once every 24 hours. (If the screen remains the same image for a long time, it may burn out and be difficult to repair.)
  • Usage Scenarios:
    • The e-Paper screen is recommended for indoor use, not for outdoor use.
    • If the usage scenario is outdoors, we cannot guarantee its display effect. If the screen is damaged due to outdoor use, we do not provide warranty service.
    • The following are some protections for outdoor use. We do not guarantee that the e-Paper can be used normally after taking these protections.
      • Avoid direct sunlight on the e-Paper screen, and at the same time take ultraviolet protection measures, because charged particles will dry out under strong light for a long time, resulting in inactivation and cannot be refreshed, which is irreversible.
      • Use 3M tape to completely cover the white plastic part on the e-Paper connection cable. Complete coverage or no tape will have different reactions under ultraviolet light.
      • Place the e-Paper in a relatively cool area, such as under the shade of trees or under the shadow of eaves.
    • When designing e-Paper products, customers should determine whether the use environment meets the requirements of e-Paper screens.


 Answer:
  • Ideally, with normal use, it can be refreshed 1,000,000 times (1 million times).


 Answer:
  • When the development board is powered on for a long time, after each refresh operation, it is recommended to set the screen to sleep mode or directly cut off the power, otherwise the screen may be burned when the e-Paper is in a high voltage state for a long time.


 Answer:
  • Yes, but you need to redo the e-paper initialization operation with the software.


 Answer:
  • The SPI rate may be too high, causing data loss, try to reduce the SPI rate.
  • Insufficient power supply or unstable power supply causes data loss.
  • The data cable is too long and causes data loss, and the extension cable should not exceed 20cm.


 Answer:
  • The gray scale of electrophoresis e-paper is determined by the spatial position of the particles in the microcapsule or microcup, and the electrophoresis phenomenon occurs between black particles and white particles under the action of voltage, and the voltage timing that prompts the electrophoretic movement of the particles is the driving waveform of the e-paper. The driving waveform is the core part of the e-paper display, and the optimization of the driving waveform will directly affect the display effect of the display. The drive waveform file is a parameter formed to describe the voltage timing that causes the electrophoretic motion of the particles, and needs to be called periodically when the e-paper is refreshed.
  • Different batches of e-paper diaphragms and electrophoretic matrices will have different voltage values ​​when driving the display due to reasons such as materials and manufacturing processes. The relationship between grayscale, voltage, and temperature is reflected in the waveform of the e-Paper screen. Generally speaking, after each batch of electrophoresis matrices is generated, there will be a corresponding waveform file in the form of a .wbf file. The membrane manufacturer will provide the waveform file and electrophoresis matrix to the manufacturer of the e-paper screen, and then the the manufacturer of the e-paper screen integrates the protective board, substrate and driver and provides them to customers later; if the waveform file does not correspond to the screen, it is likely to cause the display to fail or the display effect to be unsatisfactory. Generally, the waveform file has been OTP built into the driver IC of the e-paper screen when it leaves the factory, and some of the demos we provide also call external waveform files to drive the e-paper screen.


 Answer:
  • LUT is the abbreviation of LOOK UP TABLE, and OTP is the abbreviation of ONE TIME PROGRAM. The original meaning of LUT is to load waveform files, and waveform files are divided into two types: OTP and REGISTER. OTP is the built-in waveform storage method, and REGISTER is the external waveform storage method.


 Answer:
  • There are two main types of e-paper screens:
    • One is to refresh the background image first.
    • The other is to alternately refresh old data and new data.


 Answer:
  • Simultaneous partial refresh at different locations requires programming, that is, first refresh the data at different locations into the e-paper IC, and finally complete Updata/TurnOnDisplay in a unified manner.


 Answer:
  • Yes, there will be some color difference when e-Paper is produced in batches, which is normal. Storing the e-Paper face up can reduce the reddish/yellow cast to a certain extent.



 Answer:
  • All current screens have built-in temperature sensors, or an external LM75 temperature sensor can be used using the IIC pins.


Potential issues during development

 Answer:
  • In the config.txt file on the Raspberry Pi, no corresponding code has been added. Please refer to the Raspberry Pi Preparation to proceed Configuration


 Answer:
  • During the first refresh, the refresh of the e-Paper screen was forcibly terminated
  • After the refresh ended, it did not enter sleep mode and directly cut off the power


 Answer:
  • The power supply is insufficient, the current required for the e-Paper screen and the driver board to run is relatively large, it is recommended to use a power supply of 3.3V/1A or more to power it



Support



Technical Support

If you need technical support or have any feedback/review, please click the Submit Now button to submit a ticket, Our support team will check and reply to you within 1 to 2 working days. Please be patient as we make every effort to help you to resolve the issue.
Working Time: 9 AM - 6 PM GMT+8 (Monday to Friday)