2020-06-05 05:01 AM
Hi,
I'm working on a Touch Screen project and using STM32F746 MCU. I have an sync issue I couldn't solved yet. Here is video: https://www.youtube.com/watch?v=0T0yGYekXSE
My LTDC parameters are the same with datasheet I think there is some timing problem but I don't know what to do. Here are datasheet and my LTDC config codes.
Datasheet: https://cdn.ozdisan.com/ETicaret_Dosya/493618_9666178.pdf
LTDC Code:
/* USER CODE END LTDC_Init 1 */
hltdc.Instance = LTDC;
hltdc.Init.HSPolarity = LTDC_HSPOLARITY_AH;
hltdc.Init.VSPolarity = LTDC_VSPOLARITY_AH;
hltdc.Init.DEPolarity = LTDC_DEPOLARITY_AH;
hltdc.Init.PCPolarity = LTDC_PCPOLARITY_IPC;
hltdc.Init.HorizontalSync = 0;
hltdc.Init.VerticalSync = 0;
hltdc.Init.AccumulatedHBP = 46;
hltdc.Init.AccumulatedVBP = 23;
hltdc.Init.AccumulatedActiveW = 846;
hltdc.Init.AccumulatedActiveH = 503;
hltdc.Init.TotalWidth = 1200;
hltdc.Init.TotalHeigh = 650;
hltdc.Init.Backcolor.Blue = 0;
hltdc.Init.Backcolor.Green = 0;
hltdc.Init.Backcolor.Red = 0;
if (HAL_LTDC_Init(&hltdc) != HAL_OK)
{
Error_Handler();
}
pLayerCfg.WindowX0 = 0;
pLayerCfg.WindowX1 = 800;
pLayerCfg.WindowY0 = 0;
pLayerCfg.WindowY1 = 480;
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 = 0xC0000000;
pLayerCfg.ImageWidth = 800;
pLayerCfg.ImageHeight = 480;
pLayerCfg.Backcolor.Blue = 0;
pLayerCfg.Backcolor.Green = 0;
pLayerCfg.Backcolor.Red = 0;
2020-06-07 08:01 PM
Do you mean the flickering of the display?
2020-06-07 11:10 PM
Yes, the flickering.
2020-06-08 05:27 PM
Have you checked with a scope that you have the expected timings for pixel clock, vsync, hsync
2020-06-10 05:16 AM
I couldn't checked and can't right now but when I lower the LCD frequency (25MHz to 18Mhz) it worked. But now I added modal window and it happend again. It's like I'm losing some data.