2.13inch Touch e-Paper HAT
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Specifications
- Size: 2.13inch
- Outline dimensions(Module): 69.15 × 38.90mm
- Outline dimensions(Driver Board): 59.51mm × 34.00mm
- Display area: 48.55mm × 23.71mm
- Oerrating Voltage: 3.3V
- Communication interface: SPI
- Dot pitch: 0.194 × 0.194mm
- Resolution: 250×122 pixels
- Display color: black, white
- Grey scale: 2
- Partial refresh time: 0.3s
- Full refresh time: 2s
- Refresh power: 26.4mW(typ.)
- Touch points: 5 (MAX)
- Touch type: Capacitive touch
- Touch interfaced: I2C
- Touch panel: Toughened Glass
【Note】
- Refresh time: The refresh time is experimental test data, there will have some deviation from the actual refresh time, so please refer to the actual refresh time. The e-paper will flicker during the full refresh process, this is a normal phenomenon.
- Power consumption: The power consumption data is experimental test data. The actual power consumption will have a certain deviation due to the existence of the driver board and the actual usage. Please refer to the actual refresh power consumption.
SPI 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 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
Working protocoal
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 = 8pixels
- For example, If we set 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 computer, the data is saved in MSB format:
So we can use two bytes for 16 pixels.