Bodmer's TFT_eSPI
TFT_eSPI library test!
Benchmark Time (microseconds)
Screen fill 483570
Text 46323
Lines 568886
Horiz/Vert Lines 48273
Rectangles (outline) 28452
Rectangles (filled) 1170283
Circles (filled) 258687
Circles (outline) 206782
Triangles (outline) 116314
Triangles (filled) 503370
Rounded rects (outline) 85290
Rounded rects (filled) 1244161
Done!
#define STM32
#define ST7796_DRIVER
#define TFT_SPI_PORT 1 // SPI port 1 maximum clock rate is 55MHz
#define TFT_MOSI PA7
#define TFT_MISO PA6
#define TFT_SCLK PA5
#define TFT_CS PB3
#define TFT_DC PB10
#define TFT_RST PB12
#define SPI_FREQUENCY 55000000
I'm unsure, but it seems to work at 27MHz and not 55MHz. The speed is better, but you can still see the number blinking.
Can you give an example of how you can keep, say, the time on the screen so that it refreshes, but no flickers are visible?