• sales

    +86-0755-88291180

4.2inch e-Paper Module (B)

Introduction


Note:
 The raw panel require a driver board, If you are the first time use this e-Paper, we recommend you to buy the HAT version or buy more one driver hat for easy use, otherwise you need to make the driver board yourself. And this instruction is based on the version with PCB or driver board.

400x300, 4.2inch E-Ink display module, three-color, SPI interface


Interfaces


VCC3.3V
GNDGND
DINSPI MOSI
CLKSPI SCK
CSSPI chip select (Low active)
DCData/Command control pin (High for data, and low for command)
RSTExternal reset pin (Low for reset)
BUSYBusy state output pin (Low for busy)


Working principle


Introduction


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 sunshine, the E-paper screen still has high visibility with a wide viewing angle of 180 degree. It is the ideal choice for E-reading.


Communication protocol




Note: Different from the traditional SPI protocol, the data line from the slave to the master is hidden since the device only has display requirement.

  • CS is slave chip select, when CS is low, the chip is enabled.
  • DC is data/command control pin, when DC = 0, write command, when DC = 1, write data.
  • SCLK is the SPI communication clock.
  • SDIN is the data line from the master to the slave in SPI communication.

SPI communication has data transfer timing, which is combined by CPHA and CPOL.

  1. CPOL determines the level of the serial synchronous clock at idle state. When CPOL = 0, the level is Low. However, CPOL has little effect to the transmission.
  2. CPHA determines whether data is collected at the first clock edge or at the second clock edge of serial synchronous clock; when CPHL = 0, data is collected at the first clock edge.
  • There are 4 SPI communication modes. SPI0 is commonly used, in which CPHL = 0, CPOL = 0.

As you can see from the figure above, data transmission starts at the first falling edge of SCLK, and 8 bits of data are transferred in one clock cycle. In here, SPI0 is in used, and data is transferred by bits, MSB first.


TAG: Serial UART Bus Servo ST3025 TTL 40KG.CM Magnetic Encoder 360° High Precision And Large Torque SIM7600G H Mini PCIe SIMCom Original 4G LTE Cat-4 Module Global Coverage GNSS Raspberry Pi Pico 2 RP2350 GEEK 1.14 inch LCD 240x135 65K SWD/UART/I2C For OpenOCD/CMSIS-DAP RP2040 RP2040 LoRa Raspberry Pi Core3566102000 ESP32-S3 Development Board 3.16 inch LCD display 3.16inch Screen SD slot 320x820 RGB LED ST7701 Raspberry Pi CM5 Mini Base IO Board NANO B Development For Compute Module 5 ESP32 C3 树莓派Pico 2 RP2350B-Plus-W开发板WIFI官方Radio Module 2 ESP32 S3 Development Board 1.91 inch AMOLED Display Screen For Arduino LVGL With SD-Port/ QMI8658C 6-Axis Sensor Raspberry Pi 5 PCIe USB HUB 3.2 Gen1 HAT+ High Speed Pi5 DeepSeek AI Voice Chat ESP32 S3 Development Board 1.8 inch AMOLED Display 368×448 1.8inch TouchScreen Programmable Watch QMI8658 /MIC /Audio /Battery 3key Keyboard Development Board Milk-V Duo Camera Raspberry Pi Mini TV ESP32 1.44inch LCD RISC-V