Is Stm32f769IIT feasible with ST7701 and NT35510MH LCD IC driver?

Hello,

I don't use CUBE MX for LTDC I generate my project with LTDC to enable TouchGFX but timing are wrong in cubemx.

But you can see here revelant code.

You need to adapt your Pixel clock with your screen resolution to have the frame rate expected.

The LCD_ST7701_Init() function is your function with adapted value for my specific screen.

Please find attached full project with cubeMx, CubeIde Project and TouchGfxProject.

Best regards,

Julien.

void LCD_Init(){
	DSI_PLLInitTypeDef dsiPllInit;
	RCC_PeriphCLKInitTypeDef PeriphClkInitStruct;
	DSI_VidCfgTypeDef VidCfg = {0};
 
	//uint32_t LcdClock = 27429; /*!< LcdClk = 27429 kHz => To fast more than 120 FPS with 480*480 screen*/
	uint32_t LcdClock = 13714; /*!< LcdClk = 13714 kHz */
 
 
	uint32_t laneByteClk_kHz = 62500; /* 500 MHz / 8 = 62.5 MHz = 62500 kHz */
	uint32_t VSA = 1; /*!< Vertical start active time in units of lines */
	uint32_t VBP = 15; /*!< Vertical Back Porch time in units of lines */
	uint32_t VFP = 16; /*!< Vertical Front Porch time in units of lines */
	uint32_t VACT = GUI_HEIGHT ; /*!< Vertical Active time in units of lines = imageSize Y in pixels to display */
	uint32_t HSA = 2; /*!< Horizontal start active time in units of lcdClk */
	uint32_t HBP = 34; /*!< Horizontal Back Porch time in units of lcdClk */
	uint32_t HFP = 34; /*!< Horizontal Front Porch time in units of lcdClk */
	uint32_t HACT = GUI_WIDTH; /*!< Horizontal Active time in units of lcdClk = imageSize X in pixels to display */
 
	/* Toggle Hardware Reset of the DSI LCD using
	* its XRES signal (active low) */
	Lcd_Reset();
 
	/* Call first MSP Initialize only in case of first initialization
	* This will set IP blocks LTDC, DSI and DMA2D
	* - out of reset
	* - clocked
	* - NVIC IRQ related to IP blocks enabled
	*/
	LCD_MspInit();
 
	/*************************DSI Initialization***********************************/
 
	/* Base address of DSI Host/Wrapper registers to be set before calling De-Init */
	hdsi.Instance = DSI;
 
	HAL_DSI_DeInit(&(hdsi));
 
	dsiPllInit.PLLNDIV = 100;
	dsiPllInit.PLLIDF = DSI_PLL_IN_DIV5;
	dsiPllInit.PLLODF = DSI_PLL_OUT_DIV1;
 
	/* Set number of Lanes */
	hdsi.Init.NumberOfLanes = DSI_TWO_DATA_LANES;
 
	/* TXEscapeCkdiv = f(LaneByteClk)/15.62 = 4 */
	hdsi.Init.TXEscapeCkdiv = 4;
	//hdsi.Init.TXEscapeCkdiv = laneByteClk_kHz/15620;
 
	HAL_DSI_Init(&(hdsi), &(dsiPllInit));
 
	//To allow read
	//HAL_DSI_ConfigFlowControl(&hdsi, DSI_FLOW_CONTROL_BTA);
 
 
	VidCfg.VirtualChannelID = 0;
	VidCfg.ColorCoding = DSI_RGB888;
 
	//probably not used
	VidCfg.VSPolarity = DSI_HSYNC_ACTIVE_HIGH;
	VidCfg.HSPolarity = DSI_VSYNC_ACTIVE_HIGH;
	VidCfg.DEPolarity = DSI_DATA_ENABLE_ACTIVE_HIGH;
 
	VidCfg.LooselyPacked = DSI_LOOSELY_PACKED_DISABLE;
	VidCfg.Mode = DSI_VID_MODE_BURST; /* Mode Video burst ie : one LgP per line */
	VidCfg.NullPacketSize = 0; //0xFFF;
	VidCfg.NumberOfChunks = 0;
 
 
	VidCfg.PacketSize = HACT; /* Value depending on display orientation choice portrait/landscape */
	VidCfg.HorizontalSyncActive = (HSA * laneByteClk_kHz)/LcdClock;
	VidCfg.HorizontalBackPorch = (HBP * laneByteClk_kHz)/LcdClock;
	VidCfg.HorizontalLine = ((HACT + HSA + HBP + HFP) * laneByteClk_kHz)/LcdClock; /* Value depending on display orientation choice portrait/landscape */
	VidCfg.VerticalSyncActive = VSA;
	VidCfg.VerticalBackPorch = VBP;
	VidCfg.VerticalFrontPorch = VFP;
	VidCfg.VerticalActive = VACT; /* Value depending on display orientation choice portrait/landscape */
 
	/* Enable or disable sending LP command while streaming is active in video mode */
	VidCfg.LPCommandEnable = DSI_LP_COMMAND_ENABLE; /* Enable sending commands in mode LP (Low Power) */
 
	/* Largest packet size possible to transmit in LP mode in VSA, VBP, VFP regions */
	/* Only useful when sending LP packets is allowed while streaming is active in video mode */
	VidCfg.LPLargestPacketSize = 16;
 
	/* Largest packet size possible to transmit in LP mode in HFP region during VACT period */
	/* Only useful when sending LP packets is allowed while streaming is active in video mode */
	VidCfg.LPVACTLargestPacketSize = 0;
 
	/* Specify for each region of the video frame, if the transmission of command in LP mode is allowed in this region */
	/* while streaming is active in video mode */
	VidCfg.LPHorizontalFrontPorchEnable = DSI_LP_HFP_ENABLE; /* Allow sending LP commands during HFP period */
	VidCfg.LPHorizontalBackPorchEnable = DSI_LP_HBP_ENABLE; /* Allow sending LP commands during HBP period */
	VidCfg.LPVerticalActiveEnable = DSI_LP_VACT_ENABLE; /* Allow sending LP commands during VACT period */
	VidCfg.LPVerticalFrontPorchEnable = DSI_LP_VFP_ENABLE; /* Allow sending LP commands during VFP period */
	VidCfg.LPVerticalBackPorchEnable = DSI_LP_VBP_ENABLE; /* Allow sending LP commands during VBP period */
	VidCfg.LPVerticalSyncActiveEnable = DSI_LP_VSYNC_ENABLE; /* Allow sending LP commands during VSync = VSA period */
	VidCfg.FrameBTAAcknowledgeEnable = DSI_FBTAA_ENABLE;
 
	/* Configure DSI Video mode timings with settings set above */
	HAL_DSI_ConfigVideoMode(&hdsi, &VidCfg);
	HAL_DSI_SetGenericVCID(&hdsi, 0);
 
	/*************************End DSI Initialization*******************************/
 
 
	/************************LTDC Initialization***********************************/
 
	/* Timing Configuration */
	hltdc.Init.HorizontalSync = (HSA - 1);
	hltdc.Init.AccumulatedHBP = (HSA + HBP - 1);
	hltdc.Init.AccumulatedActiveW = (GUI_WIDTH + HSA + HBP - 1);
	hltdc.Init.TotalWidth = (GUI_WIDTH + HSA + HBP + HFP - 1);
 
	/* Initialize the LCD pixel width and pixel height */
	hltdc.LayerCfg->ImageWidth = GUI_WIDTH;
	hltdc.LayerCfg->ImageHeight = GUI_HEIGHT;
 
	/** LCD clock configuration
	* Note: The following values should not be changed as the PLLSAI is also used
	* to clock the USB FS
	* PLLSAI_VCO Input = HSE_VALUE/PLL_M = 1 Mhz
	* PLLSAI_VCO Output = PLLSAI_VCO Input * PLLSAIN = 384 Mhz
	* PLLLCDCLK = PLLSAI_VCO Output/PLLSAIR = 384 MHz / 7 = 54.85 MHz
	*
	*
	* LTDC clock frequency = PLLLCDCLK / LTDC_PLLSAI_DIVR_2 = 54.85 MHz / 2 = 27.429 MHz => Too fast MCU doesn't have time too draw between frame
	* LTDC clock frequency = PLLLCDCLK / LTDC_PLLSAI_DIVR_4 = 54.85 MHz / 4 = 13.71 MHz
	*/
	PeriphClkInitStruct.PeriphClockSelection = RCC_PERIPHCLK_LTDC;
	PeriphClkInitStruct.PLLSAI.PLLSAIN = 384;
	PeriphClkInitStruct.PLLSAI.PLLSAIR = 7;
	PeriphClkInitStruct.PLLSAIDivR = RCC_PLLSAIDIVR_4;
	HAL_RCCEx_PeriphCLKConfig(&PeriphClkInitStruct);
 
	/* Background value */
	hltdc.Init.Backcolor.Blue = 0;
	hltdc.Init.Backcolor.Green = 0;
	hltdc.Init.Backcolor.Red = 0;
	hltdc.Init.PCPolarity = LTDC_PCPOLARITY_IPC;
	hltdc.Instance = LTDC;
 
	/* Get LTDC Configuration from DSI Configuration */
	HAL_LTDC_StructInitFromVideoConfig(&hltdc, &VidCfg);
 
	/* Initialize the LTDC */
	HAL_LTDC_Init(&hltdc);
 
	/* Enable the DSI host and wrapper after the LTDC initialization
	 To avoid any synchronization issue, the DSI shall be started after enabling the LTDC */
	HAL_DSI_Start(&hdsi);
 
	LCD_ST7701_Init();
 
	//To test LTDC
	//HAL_DSI_PatternGeneratorStart(&hdsi, 0, 0);
}