STM32F429I-discovery Purple screen

grisom13 · ‎2025-08-06

Hello. This is my first week with MCU's. I choose STM and want to stick with it. But it makes only pain :) So I was able to make some GPIO to work but have a complete disaster with LCD. The board came with some demo firm, and it was erased. So I am dealing with a complete new firmware. My helper is a chat GPT but he cant fix my Purple screen. I want to print some basic text like "Hello" and have no luck. Adding code here. Please advise that else I can share so there will be a clear mistake I made. Thank you.

/* USER CODE BEGIN Header */
/**
  ******************************************************************************
  * @file           : main.c
  * @brief          : Main program body
  ******************************************************************************
  * @attention
  *
  * Copyright (c) 2025 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"
#include "stm32f429i_discovery_lcd.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;

I2C_HandleTypeDef hi2c1;

LTDC_HandleTypeDef hltdc;

SPI_HandleTypeDef hspi1;

SDRAM_HandleTypeDef hsdram1;

/* USER CODE BEGIN PV */

/* USER CODE END PV */

/* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);
static void MX_GPIO_Init(void);
static void MX_SPI1_Init(void);
static void MX_I2C1_Init(void);
static void MX_FMC_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 */

  /* 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();

  BSP_SDRAM_Init();

  BSP_LCD_Init();
  BSP_LCD_LayerDefaultInit(0, LCD_FRAME_BUFFER);
  BSP_LCD_LayerDefaultInit(1, LCD_FRAME_BUFFER + BUFFER_OFFSET);
  BSP_LCD_SelectLayer(0);
  BSP_LCD_SetFont(&LCD_DEFAULT_FONT);       // ✅ Needed

  BSP_LCD_Clear(LCD_COLOR_WHITE);

  BSP_LCD_SetBackColor(LCD_COLOR_RED);
  BSP_LCD_Clear(LCD_COLOR_BLUE);

  /* Set the LCD Text Color */
  BSP_LCD_SetTextColor(LCD_COLOR_WHITE);

  /* Display LCD messages */
  BSP_LCD_DisplayStringAt(0, 10, (uint8_t*)"Welcome", CENTER_MODE);

  /* USER CODE BEGIN SysInit */

  /* USER CODE END SysInit */

  /* Initialize all configured peripherals */
  MX_GPIO_Init();
  MX_SPI1_Init();
  MX_I2C1_Init();
  MX_FMC_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 */
  }
  /* USER CODE END 3 */
}

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

  /** Macro to configure the PLL multiplication factor
  */
  __HAL_RCC_PLL_PLLM_CONFIG(16);

  /** Macro to configure the PLL clock source
  */
  __HAL_RCC_PLL_PLLSOURCE_CONFIG(RCC_PLLSOURCE_HSI);

  /** Configure the main internal regulator output voltage
  */
  __HAL_RCC_PWR_CLK_ENABLE();
  __HAL_PWR_VOLTAGESCALING_CONFIG(PWR_REGULATOR_VOLTAGE_SCALE3);

  /** 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_ON;
  RCC_OscInitStruct.HSICalibrationValue = RCC_HSICALIBRATION_DEFAULT;
  RCC_OscInitStruct.PLL.PLLState = RCC_PLL_NONE;
  RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSI;
  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_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_HSI;
  RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
  RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV1;
  RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1;

  if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_0) != HAL_OK)
  {
    Error_Handler();
  }
}

/**
  * @brief DMA2D Initialization Function
  *  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_M2M;
	  hdma2d.Init.ColorMode = DMA2D_OUTPUT_ARGB8888;
	  hdma2d.Init.OutputOffset = 0;
	  hdma2d.LayerCfg[1].InputOffset = 0;
	  hdma2d.LayerCfg[1].InputColorMode = DMA2D_INPUT_ARGB8888;
	  hdma2d.LayerCfg[1].AlphaMode = DMA2D_NO_MODIF_ALPHA;
	  hdma2d.LayerCfg[1].InputAlpha = 0;
  if (HAL_DMA2D_Init(&hdma2d) != HAL_OK)
  {
    Error_Handler();
  }
  if (HAL_DMA2D_ConfigLayer(&hdma2d, 1) != HAL_OK)
  {
    Error_Handler();
  }
  /* USER CODE BEGIN DMA2D_Init 2 */

  /* USER CODE END DMA2D_Init 2 */

}

/**
  * @brief I2C1 Initialization Function
  *  None
  * @retval None
  */
static void MX_I2C1_Init(void)
{

  /* USER CODE BEGIN I2C1_Init 0 */

  /* USER CODE END I2C1_Init 0 */

  /* USER CODE BEGIN I2C1_Init 1 */

  /* USER CODE END I2C1_Init 1 */
  hi2c1.Instance = I2C1;
  hi2c1.Init.ClockSpeed = 100000;
  hi2c1.Init.DutyCycle = I2C_DUTYCYCLE_2;
  hi2c1.Init.OwnAddress1 = 0;
  hi2c1.Init.AddressingMode = I2C_ADDRESSINGMODE_7BIT;
  hi2c1.Init.DualAddressMode = I2C_DUALADDRESS_DISABLE;
  hi2c1.Init.OwnAddress2 = 0;
  hi2c1.Init.GeneralCallMode = I2C_GENERALCALL_DISABLE;
  hi2c1.Init.NoStretchMode = I2C_NOSTRETCH_DISABLE;
  if (HAL_I2C_Init(&hi2c1) != HAL_OK)
  {
    Error_Handler();
  }

  /** Configure Analogue filter
  */
  if (HAL_I2CEx_ConfigAnalogFilter(&hi2c1, I2C_ANALOGFILTER_ENABLE) != HAL_OK)
  {
    Error_Handler();
  }

  /** Configure Digital filter
  */
  if (HAL_I2CEx_ConfigDigitalFilter(&hi2c1, 0) != HAL_OK)
  {
    Error_Handler();
  }
  /* USER CODE BEGIN I2C1_Init 2 */

  /* USER CODE END I2C1_Init 2 */

}

/**
  * @brief LTDC Initialization Function
  *  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};
  LTDC_LayerCfgTypeDef pLayerCfg1 = {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 = 41;
  hltdc.Init.VerticalSync = 10;
  hltdc.Init.AccumulatedHBP = 54;    // 41 + 13
  hltdc.Init.AccumulatedVBP = 12;    // 10 + 2
  hltdc.Init.AccumulatedActiveW = 534;  // 480 + 54
  hltdc.Init.AccumulatedActiveH = 284;  // 272 + 12
  hltdc.Init.TotalWidth = 531;
  hltdc.Init.TotalHeigh = 284;
  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 = 239;
    pLayerCfg.WindowY0 = 0;
    pLayerCfg.WindowY1 = 319;
    pLayerCfg.PixelFormat = LTDC_PIXEL_FORMAT_ARGB8888;
    pLayerCfg.Alpha = 255;
    pLayerCfg.Alpha0 = 0;
    pLayerCfg.BlendingFactor1 = LTDC_BLENDING_FACTOR1_PAxCA;
    pLayerCfg.BlendingFactor2 = LTDC_BLENDING_FACTOR2_PAxCA;
    pLayerCfg.FBStartAdress = 0xD0000000;
    pLayerCfg.ImageWidth = 240;
    pLayerCfg.ImageHeight = 320;
    pLayerCfg.Backcolor.Blue = 0;
    pLayerCfg.Backcolor.Green = 0;
    pLayerCfg.Backcolor.Red = 0;
    if (HAL_LTDC_ConfigLayer(&hltdc, &pLayerCfg, 0) != HAL_OK)
    {
      Error_Handler();
    }
    pLayerCfg1.WindowX0 = 0;
    pLayerCfg1.WindowX1 = 239;
    pLayerCfg1.WindowY0 = 0;
    pLayerCfg1.WindowY1 = 319;
    pLayerCfg1.PixelFormat = LTDC_PIXEL_FORMAT_ARGB8888;
    pLayerCfg1.Alpha = 255;
    pLayerCfg1.Alpha0 = 0;
    pLayerCfg1.BlendingFactor1 = LTDC_BLENDING_FACTOR1_PAxCA;
    pLayerCfg1.BlendingFactor2 = LTDC_BLENDING_FACTOR2_PAxCA;
    pLayerCfg1.FBStartAdress = 0xD0050000;
    pLayerCfg1.ImageWidth = 240;
    pLayerCfg1.ImageHeight = 320;
    pLayerCfg1.Backcolor.Blue = 0;
    pLayerCfg1.Backcolor.Green = 0;
    pLayerCfg1.Backcolor.Red = 0;
    if (HAL_LTDC_ConfigLayer(&hltdc, &pLayerCfg1, 1) != HAL_OK)
    {
      Error_Handler();
  }
  /* USER CODE BEGIN LTDC_Init 2 */

  /* USER CODE END LTDC_Init 2 */

}

/**
  * @brief SPI1 Initialization Function
  *  None
  * @retval None
  */
static void MX_SPI1_Init(void)
{

  /* USER CODE BEGIN SPI1_Init 0 */

  /* USER CODE END SPI1_Init 0 */

  /* USER CODE BEGIN SPI1_Init 1 */

  /* USER CODE END SPI1_Init 1 */
  /* SPI1 parameter configuration*/
  hspi1.Instance = SPI1;
  hspi1.Init.Mode = SPI_MODE_MASTER;
  hspi1.Init.Direction = SPI_DIRECTION_2LINES;
  hspi1.Init.DataSize = SPI_DATASIZE_8BIT;
  hspi1.Init.CLKPolarity = SPI_POLARITY_LOW;
  hspi1.Init.CLKPhase = SPI_PHASE_1EDGE;
  hspi1.Init.NSS = SPI_NSS_SOFT;
  hspi1.Init.BaudRatePrescaler = SPI_BAUDRATEPRESCALER_2;
  hspi1.Init.FirstBit = SPI_FIRSTBIT_MSB;
  hspi1.Init.TIMode = SPI_TIMODE_DISABLE;
  hspi1.Init.CRCCalculation = SPI_CRCCALCULATION_DISABLE;
  hspi1.Init.CRCPolynomial = 10;
  if (HAL_SPI_Init(&hspi1) != HAL_OK)
  {
    Error_Handler();
  }
  /* USER CODE BEGIN SPI1_Init 2 */

  /* USER CODE END SPI1_Init 2 */

}

/* FMC initialization function */
static void MX_FMC_Init(void)
{

  /* USER CODE BEGIN FMC_Init 0 */

  /* USER CODE END FMC_Init 0 */

  FMC_SDRAM_TimingTypeDef SdramTiming = {0};

  /* USER CODE BEGIN FMC_Init 1 */

  /* USER CODE END FMC_Init 1 */

  /** Perform the SDRAM1 memory initialization sequence
  */
  hsdram1.Instance = FMC_SDRAM_DEVICE;
  /* hsdram1.Init */
  hsdram1.Init.SDBank = FMC_SDRAM_BANK1;
  hsdram1.Init.ColumnBitsNumber = FMC_SDRAM_COLUMN_BITS_NUM_8;
  hsdram1.Init.RowBitsNumber = FMC_SDRAM_ROW_BITS_NUM_11;
  hsdram1.Init.MemoryDataWidth = FMC_SDRAM_MEM_BUS_WIDTH_16;
  hsdram1.Init.InternalBankNumber = FMC_SDRAM_INTERN_BANKS_NUM_4;
  hsdram1.Init.CASLatency = FMC_SDRAM_CAS_LATENCY_3;
  hsdram1.Init.WriteProtection = FMC_SDRAM_WRITE_PROTECTION_DISABLE;
  hsdram1.Init.SDClockPeriod = FMC_SDRAM_CLOCK_PERIOD_2;
  hsdram1.Init.ReadBurst = FMC_SDRAM_RBURST_ENABLE;
  hsdram1.Init.ReadPipeDelay = FMC_SDRAM_RPIPE_DELAY_0;
  /* SdramTiming */
  SdramTiming.LoadToActiveDelay    = 2;
  SdramTiming.ExitSelfRefreshDelay = 7;
  SdramTiming.SelfRefreshTime      = 4;
  SdramTiming.RowCycleDelay        = 7;
  SdramTiming.WriteRecoveryTime    = 2;
  SdramTiming.RPDelay              = 2;
  SdramTiming.RCDDelay             = 2;

  if (HAL_SDRAM_Init(&hsdram1, &SdramTiming) != HAL_OK)
  {
    Error_Handler( );
  }

  /* USER CODE BEGIN FMC_Init 2 */

  /* USER CODE END FMC_Init 2 */
}

/**
  * @brief GPIO Initialization Function
  *  None
  * @retval None
  */
static void MX_GPIO_Init(void)
{
  /* 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_GPIOE_CLK_ENABLE();
  __HAL_RCC_GPIOD_CLK_ENABLE();

  /* USER CODE BEGIN MX_GPIO_Init_2 */

  /* USER CODE END MX_GPIO_Init_2 */
}

/* USER CODE BEGIN 4 */

/* USER CODE END 4 */

/**
  * @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.
  *   file: pointer to the source file name
  *   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 */

Dor_RH · ‎2025-08-07

Hello @grisom13,

I recommend checking out the example provided at this link: BSP_Example

This example might offer useful insights and solutions for your application.

For additional guidance on working with the STM32F429I-Discovery board, you can also refer to other projects available within STM32CubeF4.

I hope my answer has helped you. When your question is answered, please select this topic as the solution that answered you, as it will help others find that answer faster.

Thanks for your contribution.

Dor_RH