How to get 5" TFT LCD working with STM32H7A3 using LTDC and CubeIDE

[JNguyen]

I have STM32H7A3ZIQ Nucleo board and 5" Startek LCD KD050FWFPA011. I'd like to use CubeIDE to create code to copy an image from H7A's flash memory to the LCD using LTDC. I did get STM32H7A3ZIQ Nucleo to work with a 2" LCD using 4-wire SPI interface. The problem I have with 5" LCD is the LTDC interface. Attached is IOC file, CubeIDE code, init code from Startek, scope captures, etc.... Please help.

I got black screen. Backlight is on. IDE reports the image (Mushroom480x800) is defined but not used. Scope captures show 0x00 on pin LTDC_R4. LTDC_CLK is 24MHz, correct as designed. What do I miss?

[JNguyen]

LTDC_IRQHandler(void) is never been called. I've been looking for reason why IRQ is not generated.

From scope captures, VSYNC and HSYNC are generated continuously. RGB data lines are 0x0.

[MM..1]

Try edit generated part before you understand howto...

static void MX_LTDC_Init(void)
{
 /* USER CODE BEGIN LTDC_Init 0 */
 /* USER CODE END LTDC_Init 0 */
 LTDC_LayerCfgTypeDef pLayerCfg = {0};
 /* USER CODE BEGIN LTDC_Init 1 */
 /* USER CODE END LTDC_Init 1 */
 hltdc.Instance = LTDC;
 hltdc.Init.HSPolarity = LTDC_HSPOLARITY_AL;
 hltdc.Init.VSPolarity = LTDC_VSPOLARITY_AL;
 hltdc.Init.DEPolarity = LTDC_DEPOLARITY_AH;
 hltdc.Init.PCPolarity = LTDC_PCPOLARITY_IPC;
 hltdc.Init.HorizontalSync = 3;
 hltdc.Init.VerticalSync = 3;
 hltdc.Init.AccumulatedHBP = 33;
 hltdc.Init.AccumulatedVBP = 33;
 hltdc.Init.AccumulatedActiveW = 513;
 hltdc.Init.AccumulatedActiveH = 833;
 hltdc.Init.TotalWidth = 531;
 hltdc.Init.TotalHeigh = 853;
 hltdc.Init.Backcolor.Blue = 0;
 hltdc.Init.Backcolor.Green = 127;
 hltdc.Init.Backcolor.Red = 0;
 if (HAL_LTDC_Init(&hltdc) != HAL_OK)
 {
   Error_Handler();
 }
 pLayerCfg.WindowX0 = 0;
 pLayerCfg.WindowX1 = 480;
 pLayerCfg.WindowY0 = 0;
 pLayerCfg.WindowY1 = 800;
 pLayerCfg.PixelFormat = LTDC_PIXEL_FORMAT_RGB565;
 pLayerCfg.Alpha = 255;   //!!!
 pLayerCfg.Alpha0 = 0;
 pLayerCfg.BlendingFactor1 = LTDC_BLENDING_FACTOR1_CA;
 pLayerCfg.BlendingFactor2 = LTDC_BLENDING_FACTOR2_CA;
 //pLayerCfg.FBStartAdress = 0;
 pLayerCfg.FBStartAdress = (uint32_t)Mushroom380x600;
 pLayerCfg.ImageWidth = 480;
 pLayerCfg.ImageHeight = 800;
 pLayerCfg.Backcolor.Blue = 0;
 pLayerCfg.Backcolor.Green = 0;
 pLayerCfg.Backcolor.Red = 0;
 if (HAL_LTDC_ConfigLayer(&hltdc, &pLayerCfg, 0) != HAL_OK)
 {
   Error_Handler();
 }
 /* USER CODE BEGIN LTDC_Init 2 */
 
 /* USER CODE END LTDC_Init 2 */
}

[JNguyen]

I got the same result. LTDC IRQ is not generated. It's enable in CubeMX. Do you have any idea?

I issue ALL_PIXELS_ON/OFF commands, and LCD goes white/black. So LCD is init'ed correctly.

Scope capture shows CLK, HSYNC, DE, non-zero RGB.

[MM..1]

Check your PCLK DE and SYNC signals polarity with pdf

[JNguyen]

Startek signal names are confusing. So I checked them many times yesterday. Comparing scope capture and Startek pdf (below), it looks right.