Template: Pico e-Paper 5.83 Spec

Overview

5.83inch EPD (Electronic Paper Display) Module For Raspberry Pi Pico, 648 × 480 Pixels, Black / White, SPI Interface.

Features

• No backlight keeps displaying last content for a long time even when power down.
• Ultra-low power consumption, basically power is only required for refreshing.
• SPI interface requires minimal IO pins.
• 2 x user buttons and 1x reset button for easy interaction.

Specification

• Dimension: 5.83inch
• Outline dimensions(raw panel): 125.40mm x 99.50mm x 1.18mm
• Outline dimensions(driver board): 65mm x 31mm
• Display Size: 119.232(H) x 88.320(V)
• Operating voltage: 3.3V
• Interface: SPI
• Dot pitch: 0.184 x 0.184
• Display color: Black, White
• Resolution: 648(H) x 480(V)
• Greyscale: 2
• Full refresh time: 5s
• Refresh power: 26.4mW (typ.)
• Standby current: <0.01uA (almost none)

【Note】: Refresh time: The refresh time is the experimental test data, 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.
Power consumption: The power consumption data is the experimental test data. 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 Timing

Note: Different from the traditional SPI protocol, the data line from the slave to the master is hidden since the device only has a 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.
• Timing: CPHL=0, CPOL=0 (SPI0)

[Remarks] For specific information about SPI, 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 initial approach is to create tiny spheres, in which the charged color pigments are suspended 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 ambient light, the E-paper screen still has high visibility with a wide viewing angle of 180 degrees. It is the ideal choice for E-reading. (Note that the e-Paper cannot support updating directly under sunlight.)

Pixel & Byte

We define the pixels in a monochrome picture, 0 is black and 1 is white.
White：□: Bit 1
Black：■: Bit 0

• 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 = 8 pixels.
  
• 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:
  

For the computer, the data is saved in MSB format:

So we can use two bytes for 16 pixels.

• 5.83inch e-paper:

Because of the controller problem, it defines 0000b that the corresponding pixel is black, 0011b that the corresponding pixel is white, as 4bit = 1pixel, and the lower two bits of 4bit are 0 at the same time to show black, and vice versa, the lowest two bits of 4bit are 1 at the same time to show white, and other data will lead to uncertainty about the color of the pixel. Example:
0x00: 2 pixels ■■
0x03: 2 pixels ■□
0x30: 2 pixels □■
0x33: 2 pixels □□
Taking the 4-pixel points as an example, we assume that the first 2-pixel points are black and the last 2-pixel points are white, then the human logic is such that they are stored in order in:

For a computer, it stores data in such a way that the high bits come first and the low bits come second, and there are only 8 bits in a byte, so it is stored in the byte as follows: