Fix function ST7789_Fill_Color not fill correct color

[codead]

Hello,
function ST7789_Fill_Color is not correct because memset is not working with uint16_t data, and the uint16_t buffer should be swap 2 byte high and low . So, we have to modify this function to working correct:
`void MemsetBuffer(uint16_t buf, uint16_t data, uint32_t size)
{
while(size--)
{
buf++ = data;
}
}
/

• @brief Fill the DisplayWindow with single color
• @param color -> color to Fill with
• @return none
  */
  void ST7789_Fill_Color(uint16_t color)
  {
  uint16_t i;
  uint16_t convert_color;
  ST7789_SetAddressWindow(0, 0, ST7789_WIDTH - 1, ST7789_HEIGHT - 1);
  ST7789_Select();
  convert_color = ((color & 0xFF) << 8) | ((color & 0xFF00) >> 8);
  #ifdef LCD_USE_DMA
  for (i = 0; i < ST7789_HEIGHT / HOR_LEN; i++)
  {
  MemsetBuffer(disp_buf, convert_color, ST7789_WIDTH * HOR_LEN);
  ST7789_WriteData((uint8_t *)disp_buf, sizeof(disp_buf));
  }
  #else
  uint16_t j;
  for (i = 0; i < ST7789_WIDTH; i++)
  for (j = 0; j < ST7789_HEIGHT; j++) {
  uint8_t data[] = {color >> 8, color & 0xFF};
  ST7789_WriteData(data, sizeof(data));
  }
  #endif
  ST7789_UnSelect();
  }`

[JorikWit]

I can confirm that this is a working fix. Had the same issue. To clarify, this fix is only needed if u use DMA.

[jorgie0]

I could not get MemsetBuffer to compile using STMCubeIDE so I changed it to:
`
void MemsetBuffer(void *m, uint16_t val, size_t count) {
{
char *buf = m;
union
{
uint8_t d8[2];
uint16_t d16;
}u16 = {.d16 = val};

    while(count--)
    {
        *buf++ = u16.d8[0];
        *buf++ = u16.d8[1];
    }
    return m;
}

}
I then called it using this slightly modified code:
MemsetBuffer(disp_buf, convert_color, ST7789_WIDTH * HOR_LEN);
for (i = 0; i < ST7789_HEIGHT / HOR_LEN; i++) {
ST7789_WriteData(&disp_buf, sizeof(disp_buf));
}
`
I moved the call to 'MemsetBuffer' out of the for loop as the buffer already contains what it needs to so we are just wasting clock cycles filling it up again.

[igorpie]

My non-dma fill function with close to DMA speed.
Driver uses DMA for only fill, so it's not too useful and no memory buffer and memset needed.

void ST7789FillColor2(uint16_t color){
	int i;
	ST7789_Select();
	ST7789_SetAddressWindow(0, 0, ST7789_WIDTH - 1, ST7789_HEIGHT - 1);

	uint8_t data[] = {color >> 8, color & 0xFF};

	ST7789_DC_Set();
	for (i = 0; i < ST7789_WIDTH * ST7789_HEIGHT; i++)
		HAL_SPI_Transmit(&ST7789_SPI_PORT, data, 2, 1);
	ST7789_UnSelect();
}

And fast draw filled rectangle

void ST7789DrawFilledRectangle2(uint16_t x, uint16_t y, uint16_t w, uint16_t h, uint16_t color){
	ST7789_Select();
	int i;
	if (x >= ST7789_WIDTH || y >= ST7789_HEIGHT) return;
	if ((x + w) >= ST7789_WIDTH) w = ST7789_WIDTH - x;
	if ((y + h) >= ST7789_HEIGHT) h = ST7789_HEIGHT - y;

	ST7789_SetAddressWindow(x, y, x + w, y + h);
	uint8_t data[] = {color >> 8, color & 0xFF};
	ST7789_DC_Set();
	for (i = 0; i < w * h; i++)
		HAL_SPI_Transmit(&ST7789_SPI_PORT, data, 2, 1);
	ST7789_UnSelect();
}