SRAM internal frame Buffer - LTDC - Strange Issue

[MMARI.1]

hi,

I have successfully connected LTDC display(480x272) with STM32H723ZGT6 - RGB565 mode .

I could able to image file from internal Flash Memory .

I could able to Load Perfect colour from DMA2D by using. framebuffer in global level .

uint16_t framebuffer[480*272];

HAL_DMA2D_Start(&hdma2d, 0x000FF000,(uint32_t)framebuffer, 480, 272);
HAL_DMA2D_PollForTransfer(&hdma2d, 10);

I could not able to transfer colour from SRAM to LTDC by using .

for (int y=0; y<272; y++)
       {
          for (int x=0; x<480; x++)
  	        {
        	  framebuffer[y*480 + x] = 0xF800;
  	        }
       }

Erratic fill Screen happening when i transfer data to frame buffer memory . Even i reduced the speed of LTDC and total clock but nothing worked out .

DMA2D using same frame buffer memory and transferring register to Memory and working fine .

[STea]

Hello @MMARI.1 ,

could you please share your code as this description is not clear to me.

I could not able to transfer color from SRAM to LTDC by using.

for (int y=0; y<272; y++)
       {
          for (int x=0; x<480; x++)
  	        {
        	  framebuffer[y*480 + x] = 0xF800;
  	        }
       }

in this case is the frame buffer declared in SRAM ?

also, I would recommend you check 4861 section 7.2.5.
Regards

[MMARI.1]

How to separate the SRAM- d1 exclusive for LTDC frame buffer . how  i can directly assign the SRAM address in the LTDC Frame buffer setting . 255kb size required for frame buffer  . i can't assign the staring address the of SRAM- D1 because   mcu using some initialization data's . what should i have to include and modify in the linker file for Dividing the SRAM-D1 in to 2 .? 

/* USER CODE BEGIN Header */
/**
  ******************************************************************************
  * @file           : main.c
  * @brief          : Main program body
  ******************************************************************************
  * @attention
  *
  * Copyright (c) 2024 STMicroelectronics.
  * All rights reserved.
  *
  * This software is licensed under terms that can be found in the LICENSE file
  * in the root directory of this software component.
  * If no LICENSE file comes with this software, it is provided AS-IS.
  *
  ******************************************************************************
  */
/* USER CODE END Header */
/* Includes ------------------------------------------------------------------*/
#include "main.h"

/* Private includes ----------------------------------------------------------*/
/* USER CODE BEGIN Includes */

/* USER CODE END Includes */

/* Private typedef -----------------------------------------------------------*/
/* USER CODE BEGIN PTD */

/* USER CODE END PTD */

/* Private define ------------------------------------------------------------*/
/* USER CODE BEGIN PD */

/* USER CODE END PD */

/* Private macro -------------------------------------------------------------*/
/* USER CODE BEGIN PM */

/* USER CODE END PM */

/* Private variables ---------------------------------------------------------*/

DMA2D_HandleTypeDef hdma2d;

LTDC_HandleTypeDef hltdc;

/* USER CODE BEGIN PV */

uint16_t framebuffer[480*272];

//(uint32_t)&framebuffer;

/* USER CODE END PV */

/* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);
static void MPU_Config(void);
static void MX_GPIO_Init(void);
static void MX_DMA2D_Init(void);
static void MX_LTDC_Init(void);
/* USER CODE BEGIN PFP */

/* USER CODE END PFP */

/* Private user code ---------------------------------------------------------*/
/* USER CODE BEGIN 0 */

/* USER CODE END 0 */

/**
  * @brief  The application entry point.
  * @retval int
  */
int main(void)
{

  /* USER CODE BEGIN 1 */

  /* USER CODE END 1 */

  /* MPU Configuration--------------------------------------------------------*/
  MPU_Config();

  /* Enable the CPU Cache */

  /* Enable I-Cache---------------------------------------------------------*/
  SCB_EnableICache();

  /* Enable D-Cache---------------------------------------------------------*/
  SCB_EnableDCache();

  /* MCU Configuration--------------------------------------------------------*/

  /* Reset of all peripherals, Initializes the Flash interface and the Systick. */
  HAL_Init();

  /* USER CODE BEGIN Init */

  /* USER CODE END Init */

  /* Configure the system clock */
  SystemClock_Config();

  /* USER CODE BEGIN SysInit */

  /* USER CODE END SysInit */

  /* Initialize all configured peripherals */
  MX_GPIO_Init();
  MX_DMA2D_Init();
  MX_LTDC_Init();
  /* USER CODE BEGIN 2 */

  /* USER CODE END 2 */

  /* Infinite loop */
  /* USER CODE BEGIN WHILE */
  while (1)
  {
    /* USER CODE END WHILE */

    /* USER CODE BEGIN 3 */
	  uint16_t *p_buf = framebuffer;
	  uint16_t color_tbl[3] = {0xF800, 0x07E0, 0x001F};
	  uint16_t color;
	  static uint8_t index = 0;
	  color = color_tbl[index];
	  index = (index + 1) % 3;
	  for (int y=0; y<272; y++)
	      {
	        for (int x=0; x<480; x++)
	         {
	           p_buf[y*480 + x] = color;
	         }
	      }
	  HAL_Delay(1500);
  }
  /* USER CODE END 3 */
}

/**
  * @brief System Clock Configuration
  * @retval None
  */
void SystemClock_Config(void)
{
  RCC_OscInitTypeDef RCC_OscInitStruct = {0};
  RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};

  /** Supply configuration update enable
  */
  HAL_PWREx_ConfigSupply(PWR_LDO_SUPPLY);

  /** Configure the main internal regulator output voltage
  */
  __HAL_PWR_VOLTAGESCALING_CONFIG(PWR_REGULATOR_VOLTAGE_SCALE0);

  while(!__HAL_PWR_GET_FLAG(PWR_FLAG_VOSRDY)) {}

  /** Initializes the RCC Oscillators according to the specified parameters
  * in the RCC_OscInitTypeDef structure.
  */
  RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSI;
  RCC_OscInitStruct.HSIState = RCC_HSI_DIV1;
  RCC_OscInitStruct.HSICalibrationValue = 64;
  RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
  RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSI;
  RCC_OscInitStruct.PLL.PLLM = 4;
  RCC_OscInitStruct.PLL.PLLN = 34;
  RCC_OscInitStruct.PLL.PLLP = 1;
  RCC_OscInitStruct.PLL.PLLQ = 2;
  RCC_OscInitStruct.PLL.PLLR = 2;
  RCC_OscInitStruct.PLL.PLLRGE = RCC_PLL1VCIRANGE_3;
  RCC_OscInitStruct.PLL.PLLVCOSEL = RCC_PLL1VCOWIDE;
  RCC_OscInitStruct.PLL.PLLFRACN = 3072;
  if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK)
  {
    Error_Handler();
  }

  /** Initializes the CPU, AHB and APB buses clocks
  */
  RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_HCLK|RCC_CLOCKTYPE_SYSCLK
                              |RCC_CLOCKTYPE_PCLK1|RCC_CLOCKTYPE_PCLK2
                              |RCC_CLOCKTYPE_D3PCLK1|RCC_CLOCKTYPE_D1PCLK1;
  RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;
  RCC_ClkInitStruct.SYSCLKDivider = RCC_SYSCLK_DIV1;
  RCC_ClkInitStruct.AHBCLKDivider = RCC_HCLK_DIV2;
  RCC_ClkInitStruct.APB3CLKDivider = RCC_APB3_DIV2;
  RCC_ClkInitStruct.APB1CLKDivider = RCC_APB1_DIV2;
  RCC_ClkInitStruct.APB2CLKDivider = RCC_APB2_DIV2;
  RCC_ClkInitStruct.APB4CLKDivider = RCC_APB4_DIV2;

  if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_3) != HAL_OK)
  {
    Error_Handler();
  }
}

/**
  * @brief DMA2D Initialization Function
  * @PAram None
  * @retval None
  */
static void MX_DMA2D_Init(void)
{

  /* USER CODE BEGIN DMA2D_Init 0 */

  /* USER CODE END DMA2D_Init 0 */

  /* USER CODE BEGIN DMA2D_Init 1 */

  /* USER CODE END DMA2D_Init 1 */
  hdma2d.Instance = DMA2D;
  hdma2d.Init.Mode = DMA2D_R2M;
  hdma2d.Init.ColorMode = DMA2D_OUTPUT_RGB565;
  hdma2d.Init.OutputOffset = 0;
  if (HAL_DMA2D_Init(&hdma2d) != HAL_OK)
  {
    Error_Handler();
  }
  /* USER CODE BEGIN DMA2D_Init 2 */

  /* USER CODE END DMA2D_Init 2 */

}

/**
  * @brief LTDC Initialization Function
  * @PAram None
  * @retval None
  */
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_AL;
  hltdc.Init.PCPolarity = LTDC_PCPOLARITY_IPC;
  hltdc.Init.HorizontalSync = 3;
  hltdc.Init.VerticalSync = 3;
  hltdc.Init.AccumulatedHBP = 46;
  hltdc.Init.AccumulatedVBP = 15;
  hltdc.Init.AccumulatedActiveW = 526;
  hltdc.Init.AccumulatedActiveH = 287;
  hltdc.Init.TotalWidth = 534;
  hltdc.Init.TotalHeigh = 295;
  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 = 480;
  pLayerCfg.WindowY0 = 0;
  pLayerCfg.WindowY1 = 272;
  pLayerCfg.PixelFormat = LTDC_PIXEL_FORMAT_RGB565;
  pLayerCfg.Alpha = 255;
  pLayerCfg.Alpha0 = 255;
  pLayerCfg.BlendingFactor1 = LTDC_BLENDING_FACTOR1_CA;
  pLayerCfg.BlendingFactor2 = LTDC_BLENDING_FACTOR2_CA;
  pLayerCfg.FBStartAdress = (uint32_t)&framebuffer;
  pLayerCfg.ImageWidth = 480;
  pLayerCfg.ImageHeight = 272;
  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 */

}

/**
  * @brief GPIO Initialization Function
  * @PAram None
  * @retval None
  */
static void MX_GPIO_Init(void)
{
  GPIO_InitTypeDef GPIO_InitStruct = {0};
/* USER CODE BEGIN MX_GPIO_Init_1 */
/* USER CODE END MX_GPIO_Init_1 */

  /* GPIO Ports Clock Enable */
  __HAL_RCC_GPIOF_CLK_ENABLE();
  __HAL_RCC_GPIOC_CLK_ENABLE();
  __HAL_RCC_GPIOA_CLK_ENABLE();
  __HAL_RCC_GPIOB_CLK_ENABLE();
  __HAL_RCC_GPIOD_CLK_ENABLE();

  /*Configure GPIO pin Output Level */
  HAL_GPIO_WritePin(GPIOB, GPIO_PIN_8, GPIO_PIN_SET);

  /*Configure GPIO pin : PB8 */
  GPIO_InitStruct.Pin = GPIO_PIN_8;
  GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
  HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);

/* USER CODE BEGIN MX_GPIO_Init_2 */
/* USER CODE END MX_GPIO_Init_2 */
}

/* USER CODE BEGIN 4 */

/* USER CODE END 4 */

 /* MPU Configuration */

void MPU_Config(void)
{
  MPU_Region_InitTypeDef MPU_InitStruct = {0};

  /* Disables the MPU */
  HAL_MPU_Disable();

  /** Initializes and configures the Region and the memory to be protected
  */
  MPU_InitStruct.Enable = MPU_REGION_ENABLE;
  MPU_InitStruct.Number = MPU_REGION_NUMBER0;
  MPU_InitStruct.BaseAddress = 0x0;
  MPU_InitStruct.Size = MPU_REGION_SIZE_4GB;
  MPU_InitStruct.SubRegionDisable = 0x87;
  MPU_InitStruct.TypeExtField = MPU_TEX_LEVEL0;
  MPU_InitStruct.AccessPermission = MPU_REGION_NO_ACCESS;
  MPU_InitStruct.DisableExec = MPU_INSTRUCTION_ACCESS_DISABLE;
  MPU_InitStruct.IsShareable = MPU_ACCESS_SHAREABLE;
  MPU_InitStruct.IsCacheable = MPU_ACCESS_NOT_CACHEABLE;
  MPU_InitStruct.IsBufferable = MPU_ACCESS_NOT_BUFFERABLE;

  HAL_MPU_ConfigRegion(&MPU_InitStruct);
  /* Enables the MPU */
  HAL_MPU_Enable(MPU_PRIVILEGED_DEFAULT);

}

/**
  * @brief  This function is executed in case of error occurrence.
  * @retval None
  */
void Error_Handler(void)
{
  /* USER CODE BEGIN Error_Handler_Debug */
  /* User can add his own implementation to report the HAL error return state */
  __disable_irq();
  while (1)
  {
  }
  /* USER CODE END Error_Handler_Debug */
}

#ifdef  USE_FULL_ASSERT
/**
  * @brief  Reports the name of the source file and the source line number
  *         where the assert_param error has occurred.
  * @PAram  file: pointer to the source file name
  * @PAram  line: assert_param error line source number
  * @retval None
  */
void assert_failed(uint8_t *file, uint32_t line)
{
  /* USER CODE BEGIN 6 */
  /* User can add his own implementation to report the file name and line number,
     ex: printf("Wrong parameters value: file %s on line %d\r\n", file, line) */
  /* USER CODE END 6 */
}
#endif /* USE_FULL_ASSERT */

i 

[MM..1 · Accepted solution]

Primary change two lines to by address mode :

//uint16_t framebuffer[480*272];
#define FBUF 0x... //reserved memory add start in Dx must be alligned for ltdc limits
...
pLayerCfg.FBStartAdress = (uint32_t)FBUF;

and in linker script setup RAM areas and sizes .

But when DMA2D into actual buf works, then maybe other mistake in your config. Check MPU and optimize level can remove your code , because filled p_buf is never used... change it to framebuffer and declare volatile.