2.13inch E-Ink Display HAT for Raspberry Pi

Product Overview

This product is a 2.13-inch ink screen expansion module, based on the Raspberry Pi 40PIN interface design and suitable for Raspberry Pi series motherboards. We provide C and Python version demo codes for Raspberry Pi, and reserve the SPI control interface for easy access to Arduino, STM32 and other main control boards. We also provide Arduino, STM32, ESP32 version demo codes, which can realize picture display, English and digital character display, and point, line, rectangle, circle drawing.

Features

250 x 122 pixels
SPI interface, less pin occupation
Onboard Voltage Translator, which can be compatible with 3.3V and 5V MCUs
Based on Raspberry Pi 40PIN GPIO header design, applicable to Raspberry Pi series motherboard
SPI communication interface is reserved to facilitate connect to Arduino/STM32 and other control boards
Open source demo codes available for Raspberry Pi, Arduino Mega, STM32, ESP32 development boards

Specifications

Size	65mm(Length) x 30mm(width)
Pixels	250 x 122
Display Color	monochrome(Black and white)
Voltage Translator	TXS0108EPWR
Signal interface	SPI
Supply voltage	3.3V/5V
LCD display area	23.7046mm (W) x 48.55mm (H)
Partial Refresh	0.3S (4-wire SPI status)
Global Refresh	2S (4-wire SPI status)

Usage

Precautions for using the E-Paper

Avoid direct sunlight. Electronic paper will display particles under strong light, that is, the charged particles in the microcapsules will dry out under strong light, and then lose their activity and cannot be refreshed. This condition is irreversible. At the same time, moisture-proof and waterproof measures must be taken, and the operation should be strictly in accordance with the temperature and humidity range required by the specification. If the electronic paper is not used for a long time, it needs to be placed upside down, and the screen should be placed with a full white screen.
After the electronic paper is refreshed, you need to set the sleep mode, or turn off the power after setting the sleep mode. The refresh interval of the SPI serial port electronic paper is at least 180s, especially for large-sized electronic paper, if the interval is too short, afterimages will appear, which will affect the display effect of the electronic paper.
In order to reduce afterimages, it is recommended to add black and white full-screen refresh display after 5 partial refreshes, and increase the refresh interval.
If the E-Paper is not refreshed for a long time, it must be powered off or enter the deep sleep mode.
The EPD Panel / Module is manufactured from fragile materials such as glass and plastic, and may be broken or cracked if dropped. Please handle with care. Do not apply force such as bending or twisting to the EPD panel .
High temperature, high humidity, sunlight or fluorescent light may degrade the EPD panel's performance. Please do not expose the unprotected EPD panel to high temperature, high humidity, sunlight, or fluorescent for long periods of time. Please store the EPD panel in controllable environment of warehouse and original package.

All the demo codes provided by this product are based on the 4-wire SPI mode, so the BS selection switch on the back of the board is set to "0" by default.

Module Resource Profile

Module Resource Profile is shown in the figure below:

1. SPI line number selector switch

2. Reserved SPI connector

3. Raspberry Pi 40PIN header

4. E-Ink display connector

Raspberry Pi Demo Codes Usage

Since the bookworm system no longer supports the wiringpi library, the example program for this system uses the lgpio library, and for the bullseye system, the wiringpi library version of the example program can be used.

Raspberry Pi Platform Interface Definition

The example program used in the Raspberry Pi motherboard employs pin definitions numbered with wiringPi, and the bookworm system uses the pin definition of the BCM number. The definition of the wiring with the Raspberry Pi motherboard is shown in the following table:

E-Ink display	Pin function	BCMnumber
VCC	3.3V
GND	GND
BUSY	P5	24
RSTN	P0	17
D/C	P6	25
SDA	P_MOSI	10
SCL	P_SCK	11
CSB	P_CE0	8

Table2-1 Definition of E-Ink display and Raspberry Pi pin

Wiringpi library installation

sudo apt-get install wiringpi
wget https://project-downloads.drogon.net/wiringpi-latest.deb # Raspberry Pi 4B version upgrade
sudo dpkg -i wiringpi-latest.deb
gpio -v # If version 2.52 appears, the installation is successful

Python:

pip install wiringpi

lgpio library installation

wget https://github.com/joan2937/lg/archive/master.zip
unzip master.zip
cd lg-master
make
sudo make install

Open SPI interface

sudo raspi-config

Enable SPI interface:

Interfacing Options->SPI->Yes

To view enabled SPI devices:

ls /dev/spi*

The following will be printed: "/dev/spidev0.0" and "/dev/spidev0.1"

Installation of python library

The demo codes uses the python 3 environment. To run the python demo codes, you need to install the pil, numpy, and spiderv libraries. Enter the following commands in order to install:

sudo apt-get install python3-pil
sudo apt-get install python3-numpy
sudo apt-get install python3-pip
sudo apt-get install spidev

C version demo codes

Enter2.13inch E-Paper Display\demo codes\raspberry_pi\c directory

sudo make clean
sudo make
sudo ./main

After entering the above command, you can observe the E-Ink display.

python Version demo codes

Enter 2.13inch E-Paper Display\demo codes\raspberry_pi\python directory

python3 gui_demo.py

After entering the above command, you can observe the E-Ink display.

Arduino Demo Codes Usage

Hardware interface configuration description

Table 4-2 is the wiring definition between Arduino Mega and ink screen:

E-Ink display	Arduino Mega
VCC	5V
GND	GND
CS	D53
CLK	D52
MOSI	D51
DC	D8
RST	D9
BUSY	D10

Table 4-2 Pin definition of ink screen and Arduino Mega

Table 4-3 is the wiring definition between Arduino UNO and ink screen:

E-Ink display	Arduino UNO
VCC	5V
GND	GND
CS	D11
CLK	D12
MOSI	D13
DC	D10
RST	D9
BUSY	D8

Table 4-3 Pin definition of ink screen and Arduino UNO

Demo Codes Usage

Open the \demo codes\Arduino_MEGA_2.13_V2\Arduino_MEGA_2.13_V2.ino or \demo codes\Arduino_UNO_2.13_V2\Arduino_UNO_2.13_V2.ino with Arduino IDE Click Verify to verify the project file, and then transfer it to the module to observe the E-Ink display.

STM32 Demo Codes Usage

Hardware interface configuration description

E-Ink display	STM32
VCC	3.3V
GND	GND
CS	PB12
CLK	PB13
MOSI	PB15
DC	PA8
RST	PA11
BUSY	PA12

Demo Codes Usage

Open the demo codes in directory \demo codes\STM32 with Keil uVision5 software, compile it correctly, download it to the module, and observe the E-Ink display.

ESP32 Demo Codes Usage

The ESP32 module used in this example program is ESP32-WROOM-32E.

Hardware interface configuration description

E-Ink display	ESP32
VCC	3.3V
GND	GND
CS	IO27
CLK	IO18
MOSI	IO23
DC	IO14
RST	IO33
BUSY	IO13

Demo Codes Usage

Open the demo codes in directory \demo codes\Arduino_ESP32_2.13_V2\ with Arduino IDE Click Verify to verify the project file, and then transfer it to the module to observe the E-Ink display.

Image Creation and Modeling Instructions

Image Creation

Create images that need to be displayed in 250 x 122 resolution as pure black and white images (grayscale is not supported), save them as BMP or JPG files (BMP format is recommended).

Modeling

Modeling can be done using the "image2lcd" software provided in the compressed package. the modeling parameter setting interface is shown in Figure 2-2:

1. Open the image that needs to be modeled.

2. Output data type: Select "C Language Array (*.c)".

3. Scanning method: Choose "Vertical scanning".

4. Output grayscale: Select "Monochrome".

5. Maximum width and height: Choose "250" "122". After selection, click the arrow next to it to confirm.

6. Do not check any of the 5 items as shown in the figure below.