Origianl Floyd-Fish lib has a problem with color output when using DMA - colors are mixed up. The code may not compile at all with an error, or produce firmware with mixed up colors during DMA
-Correct display of colors with DMA
-Removed interference on the screen when turning on
-Added functions for drawing using DMA
Using STM32's Hardware SPI(with simple DMA support) to drive a ST7789 based LCD display.
- Copy the "st7789" dir to your project src path, add it to include path
- Include
"st7789.h"in where you want to use this driver. - Configure parameters in
"st7789.h"according to your own display panel - In system startup, perform
ST7789_Init();. - Run a
ST7789_Test()to exam this driver. - Run a
ST7789_TestColors()to test colors - Don't forget to turn the backlight on
This code has been tested on 240x240 & 170x320 LCD screens.
Most MCUs don't have a large enough RAM, so a framebuffer is "cut" into pieces, e.g: a 240x5 pixel buffer for a 240x240 screen.
If you are using Dupont Line(or jumper wire), please notice that your CLK frequency should not exceed 40MHz (may vary, depends on the length of your wire), otherwise data transfer will collapse!
For higher speed applications, it's recommended to use PCB rather than jumper wires.
In STM32CubeMX/CubeIDE, config the SPI params as follow:
I've had a simple test, connect the screen and mcu via 20cm dupont line, and it works normally on 21.25MB/s. And if I connect a logic analyzer to the clk and data lines(15cm probe), 21.25MB/s doesn't work anymore, I have to lower its datarate to 10.625MB/s. Using PCB to connect the display, it works up to 40MB/s and still looks nice.
- 135*240
- 240*240
- 170*320 (new)
If you like, you could customize it's resolution to drive different displays you prefer.
For example, a 240x320 display is perfectly suited for st7789.
Just set all X_SHIFT and Y_SHIFT to 0, and set resolution to 240|320.
For more details, please refer to ST7789's datasheet.