• sales

    +86-0755-88291180

2.9inch e-Paper HAT (D)

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.




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: R7FA4 Plus A Board Based on R7FA4M1AB3CFM Compatible with Arduino UNO For R4 Minima Jetson Nano 3G module ESP32 Raspberry Pi Pico 2 RP2350 Pico2 ARM Cortex-M33 And RISC-V Hazard3 520KByte 4MByte QSPI Flash Raspberry Pi 18.5inch FHD LCD 1920x1080 Capacitive TouchScreen Display For Raspberry Pi/Jetson Nano/ Milk V JETSON-NANO-MINI X1006 Raspberry Pi 5 PCIe To 2.5 SATA And M.2 KEY-B 2280 SSD/HDD Double-SATA (NOT BOOT From SATA/SSD Bus servo driver board Raspberry Pi 5 DSI display Raspberry Pi 14 inch LCD 2K HDMI /Type C Display Capacitive TouchScreen 2160x1440 For Jetson Nano/mini Computer PC Raspberry-Pi-A7670E-GSM-GPRS-GNSS-LTE-Cat-1-2G-A-User-Guide ESP32 C3 ST7735 Mechanical Keyboard PI5 Case Changeable Photo Frames Raspberry Pi 5/4B easy Adapter Micro HDMI to HDMI 4K All Ports To Pi's USB Side Mini Uninterruptible Power Supply module Supports charging And Power output at the same time 5V 2.5A Font-Modulation-Tutorial User Guide Raspberry Pi 5 PCIe to M.2 NVMe SSD Adapter Board (D) HAT Pi5-2280-2242-2230