Use Pico-ePaper-2.13 display on Duo S

Working Principle

Using SPI communication interface, the "microcapsule electrophoresis display" technology is used for image display. The basic principle is that charged nanoparticles suspended in liquid migrate under the action of electric field. The electronic paper display screen displays patterns by reflecting ambient light and does not require backlight. Under ambient light, the electronic paper display screen is clearly visible, and the viewing angle reaches almost 180°. Therefore, the electronic paper display screen is very suitable for reading.

Hardware wiring

Connection name	GND	VCC	DC	CS	RST	BUSY	CLK	DIN
Pin	GND	VCC (3.3V)	PIN50	PIN11	PIN13	PIN46	PIN23	PIN19

Build the operating environment

Reference:https://github.com/milkv-duo/duo-examples

Compile c

git clone https://github.com/zwyzwm/Pico-ePaper-2.13.git

After downloading and compiling, run the command scp [email protected]:/root/, copy the generated paper to the login terminal, and run the program.

Display characters

• Take the character size of Font16 as an example:

In the main function, call Paint_DrawString_EN(5, 10, "HELLO", &Font16, WHITE, BLACK);, and the character HELLO can be displayed vertically.

Display black dots

• Take the black dot size of 2x2 as an example:

In the main function, call Paint_DrawPoint(2, 2, BLACK, DOT_PIXEL_2X2, DOT_STYLE_DFT);, and the black dots can be displayed vertically.

In the main function, call Paint_DrawPoint(250,122, BLACK, DOT_PIXEL_2X2, DOT_STYLE_DFT);, and the black dots can be displayed in the lower right corner.

Display the image

• Reduce the resolution of the jpg image to 250x122

Run resize_image.py to get a jpg image with a resolution of 250x122.

• Convert the jpg format to bmp

In the terminal in the same directory, run the command covert input.jpg output.bmp to get a bmp format image.

• Convert the bmp format image to a black and white image

In the terminal in the same directory, run the command convert input.bmp -colorspace Gray output.bmp to get a black and white image.

• Modulo the image to get the modulo array

For reference: https://github.com/riuson/lcd-image-converter

Or for simpler images, you can run Modulo_array.py to get the hexadecimal array and copy the array to the ImageData.c file

• Display the image Call Paint_DrawBitMap(your arrays); in the main function to display the image.