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{{Infobox item
|name=2.7inch e-Paper (B)
|name2=2.7inch e-Paper HAT (B)
|img=[[File:2.7inch-e-Paper-B-1.jpg|300px|{{Amazon_nolink|default={{#ifeq: {{#urlget:amazon|0}}|{{#urlget:Amazon|0}}| default|}}|url=link=}}]]
|img2=[[File:2.7inch-e-paper-hat-b-4.jpg|300px|{{Amazon_nolink|default={{#ifeq: {{#urlget:amazon|0}}|{{#urlget:Amazon|0}}| default|}}|url=link=}}]]
|caption=264x176, 2.7inch EPD panel
|caption2=264x176, 2.7inch EPD HAT for Raspberry Pi, three-color
|category=[[:Category:OLEDs / LCDs|OLEDs / LCDs]], [[:Category:LCD|LCD]]
|{{#ifeq: {{#urlget:amazon|0}}|{{#urlget:Amazon|0}}| default|}}=display
|website_cn=[ 官方中文站点]
|website_en=[ Waveshare website]
{{Product List|OLEDs / LCDs/e-Paper}}
<div class="tabber">
<div class="tabbertab" title="Introduction">
<font backgound=white; color=#DD1223>
The 2.7inch e-Paper (B) raw panel was updated to the V2 version. The controller and the driver codes are different and the codes of the two versions are not compatible with each other. Except for the software, the outline of the two versions is the same. If you are the regulars of this display, please note that you need to update your driver codes with the new version refer to our new examples for the V2 version. if your the first time buy and use this display, just need to download and use the new V2 examples. The V2 version has a "V2" sticker on the backside of the display panel. Please confirm the version by the sticker.
{{E-Paper Raw Panel}}
264x176, 2.7inch EPD (Electronic Paper Display) HAT for Raspberry Pi, three-color
{{Amazon|{{#ifeq: {{#urlget:amazon|0}}|{{#urlget:Amazon|0}}| default|}}=display
|More = [ More]}}
*Size: 2.7inch
*Outline dimensions(raw panel): 70.42mm × 45.8mm × 0.98mm
*Outline dimension(driver board):73.5mm × 56.0mm
*Sisplay voltage: 73.5mm × 56.0mm
*Operating voltage: 3.3V/5V
*Interface: SPI
*Dot pitch: 0.217 × 0.217
*Resolution: 264 × 176
*Grey level: 2
*Full refresh time: 15s
*Refresh power: 26.4mW(typ.)
*Standby current: <0.01uA(almost none)
1. Refresh time: The refresh time is the experimental results, the actual refresh time will have errors, and the actual effect shall prevail. There will be a flickering effect during the global refresh process, this is a normal phenomenon
2. Power consumption: The power consumption data is the experimental results. The actual power consumption will have a certain error due to the existence of the driver board and the actual use situation. The actual effect shall prevail.
==SPI Communication Timing==
Since the ink screen only needs to be displayed, the data cable (MISO) sent from the machine and received by the host is hidden here.
*CS: Slave chip select, when CS is low, the chip is enabled
*DC: data/command control pin, write command when DC=0; write data when DC=1
*SCLK: SPI communication clock
*SDIN: SPI communication master sends, slave receives
*Timing: CPHL=0, CPOL=0 (SPI0)
[Remarks] For specific information about SPI, you can search for information online.<big>
==Working Protocol==
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 displays patterns by reflecting the ambient light, so it has no background light requirement. ('''Note that the e-Paper cannot support updating directly under sunlight''').
===How to define pixels===
In a monochrome picture we define the pixels, 0 is black and 1 is white.<br />
White:□,Bit 1<br />
Black:■:Bit 0<br />
*The dot in the figure is called a pixel. As we know, 1 and 0 are used to define the color, therefore we can use one bit to define the color of one pixel, and 1 byte = 8pixels<br />
*For example, If we set the first 8 pixels to black and the last 8 pixels to white, we show it by codes, they will be 16 bit as below:<br />
[[file:e-paper_hardware_work_1.png]]<br />
For computer, the data is saved in MSB format:<br />
[[file:e-paper_hardware_work_2.png]]<br />
So we can use two bytes for 16 pixels.<br />
For 2.7inch e-paper B, the display colors are red, black, and white. We need to split the picture into 2 pictures, one is the black and white picture, another is the red and white picture. When transmitting, because one register controls a black or white pixel, one controls Red or white display. The black and white part of 2.7 use 1 byte to control 8 pixels, and the red and white part use 1 byte to control 8 pixels.<br />
For example, suppose there are 8 pixels, the first 4 are red, and the back 4 are black:<br />
They need to be disassembled into a black and white picture and a red and white picture. Both pictures have 8 pixels, but the first four pixels of the black and white picture are white, the last 4 pixels are black, and the first 4 pixels of the red and white picture One pixel is red, and the last four pixels are white. <br />
If you define that the data of white pixel is 1 and the black is 0, then we can get:
So that we can use 1 byte to control every eight pixels.
#For the screen that supports partial update, please note that you cannot refresh the screen with the partial mode all the time. After several partial updating, you need to fully refresh the screen once. Otherwise, the screen display effect will be abnormal, which cannot be repaired!<br/>
#Because of the different batches, some of them have aberrations. Store the e-Paper right side up will reduce it. And if the e-Paper didn't be refreshed for a long time, it will become more and more reddish/yellowish. Please use the demo code to refresh the e-paper several times in this case.<br/>
#Note that the screen cannot be powered on for a long time. When the screen is not refreshed, please set the screen to sleep mode, or power off the e-Paper. Otherwise, the screen will remain in a high voltage state for a long time, which will damage the e-Paper and cannot be repaired!<br/>
#When using the e-Paper, it is recommended that the refresh interval be at least 180s, and refresh at least once every 24 hours. If the e-Paper is not used for a long time, the ink screen should be brushed and stored. (Refer to the datasheet for specific storage environment requirements)<br/>
#After the screen enters sleep mode, the sent image data will be ignored, and it can be refreshed normally only after initializing again.<br/>
#Control the 0x3C or 0x50 (refer to the datasheet for details) register to adjust the border color. In the routine, you can adjust the Border Waveform Control register or VCOM AND DATA INTERVAL SETTING to set the border.<br/>
#If you find that the created image data is displayed incorrectly on the screen, it is recommended to check whether the image size setting is correct, change the width and height settings of the image and try again.<br/>
#The working voltage of the e-Paper is 3.3V. If you buy the raw panel and you need to add a level convert circuit for compatibility with 5V voltage. The new version of the driver board (V2.1 and subsequent versions) has added a level processing circuit, which can support both 3.3V and 5V working environments. The old version can only support a 3.3V working environment. You can confirm the version before using it. (The one with the 20-pin chip on the PCB is generally the new version)<br/>
#The FPC cable of the screen is relatively fragile, pay attention to bending the cable along the horizontal direction of the screen when using it, and do not bend the cable along the vertical direction of the screen<br/>
#The screen of e-Paper is relatively fragile, please try to avoid dropping, bumping, and pressing hard.<br/>
#We recommend that customers use the sample program provided by us to test with the corresponding development board after they get the screen.<br/>
<div style="background-color: #343434;text-align: center;color: white;padding: 20px;margin: 8px;">
=2.7inch e-Paper HAT (B) Manual=
<div class="tabbertab" title="Hardware/Software setup">
{{Hardware/Software setting for SPI e-paper}}
|content =
<div class="tabbertab" title="Codes description">
{{e-Paper Codes Description}}
<div class="tabbertab" title="Resources">
|heading = Introduction
|content = Parameters, principles, and precautions
|img=[[File:Tinker Board 2硬件-test1.png|121px|link=]]
|heading = Starting from the Arduino
|content = Routines developed based on Arduino UNO R3 and their usage instructions
*[ User Manual]
{{Commom Instruction of SPI e-paper}}
|heading = Start with Raspberry Pi
* [[:File:2.7inch_e-Paper_HAT_Schematic.pdf|Schematic]]
|content = Using BCM2835, WiringPi, file IO, RPI (Python) library development routines and instructions
==Demo code==
*[[:File:E-Paper_code (3).7z | Sample Program]]
*[ Github]
|heading = Start with the Jetson Nano
|content = Use C language, Python developed routines and instructions
* [[:File:2.7inch-e-paper-b-specification.pdf|Datasheets]]
*[ 2.7inch e-Paper (B) V2 Specification]
|heading = Starting from the STM32
|content = Use STM32CubeMX to develop routines based on STM32F103ZET6 and their usage instructions
==Related Resources==
This is a post in Arduino Form about our SPI e-Paper thanks to ZinggJM, maybe you want to refer to.
*[ Waveshare e-Paper display with SPI]
|heading = Resources
|content = Documentation, procedures and data sheets, etc
==Related applications==
*[ Raspberry Pi E-paper Display demo]
|heading = FAQ
|content = e-Paper frequently asked questions
<div class="tabbertab" title="FAQ">
|heading = Support
|content = Technical support
= FAQ =
{{e-paper Hat FAQ}}
=== Display a Frame (DisplayFrame) ===
DisplayFrame is used to send a frame to module, and the screen will refresh and display it.
Process: Send command data start transmission 1 -> Send data of dark area -> Send command data start transmission 2 -> Send data of red area -> Refresh the screen.
* One frame consist of images of black area and red area, so we need to send two images for displaying one frame,
* 1 byte = 8 pixels, doesn’t support Gray scale (Can only display black and white). A bit set stands for black/red pixel, otherwise a bit reset stands for white.
For example:
0xC3:8 pixels ■■□□□□■■
0x00:8 pixels □□□□□□□□
0xFF:8 pixels ■■■■■■■■
0x66:8 pixels □■■□□■■□
* This module doesn’t support partial refresh.
* The refresh rate of this module is slow, and it will flicker for several times during refreshing (about 15s). Please be patient.

Latest revision as of 09:53, 21 July 2022

2.7inch e-Paper HAT (B) Manual



Parameters, principles, and precautions
Tinker Board 2硬件-test1.png

Starting from the Arduino

Routines developed based on Arduino UNO R3 and their usage instructions

Start with Raspberry Pi

Using BCM2835, WiringPi, file IO, RPI (Python) library development routines and instructions

Start with the Jetson Nano

Use C language, Python developed routines and instructions

Starting from the STM32

Use STM32CubeMX to develop routines based on STM32F103ZET6 and their usage instructions


Documentation, procedures and data sheets, etc


e-Paper frequently asked questions


Technical support