/* 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"

/* 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 ---------------------------------------------------------*/

DMA_HandleTypeDef hdma_memtomem_dma1_stream0;
/* USER CODE BEGIN PV */

/* USER CODE END PV */

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

/* USER CODE END PFP */

/* Private user code ---------------------------------------------------------*/
/* USER CODE BEGIN 0 */
void XferCpltCallback(DMA_HandleTypeDef *hdma);
uint8_t Buffer_Src[] = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 };
uint8_t Buffer_Dest[10];
volatile uint32_t gpio_value; // To store the 32-bit GPIO register value
volatile uint8_t transfer_complete = 0; // Flag to indicate transfer completion
volatile uint32_t toggle_counter = 0; // Counter to slow down pin toggling
#define TOGGLE_DIVIDER 100 // Slow down by 100x
/* 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();

  /* 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_DMA_Init();
  MX_GPIO_Init();
  /* USER CODE BEGIN 2 */
	hdma_memtomem_dma1_stream0.XferCpltCallback = &XferCpltCallback;

	// CRITICAL: Enable GPIOA clock first!
	__HAL_RCC_GPIOA_CLK_ENABLE();
	
	// Configure only a few safe GPIOA pins to test
	GPIO_InitTypeDef GPIO_InitStruct = { 0 };
	GPIO_InitStruct.Pin = GPIO_PIN_0 | GPIO_PIN_1 | GPIO_PIN_2 | GPIO_PIN_3 | GPIO_PIN_4 | GPIO_PIN_5;  // Just PA0 and PA1 for testing
	GPIO_InitStruct.Mode = GPIO_MODE_INPUT;
	GPIO_InitStruct.Pull = GPIO_PULLDOWN; // Pull down makes pins read as 0 when unconnected
	

	
	HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);

	HAL_DMA_Start_IT(&hdma_memtomem_dma1_stream0, (uint32_t) &GPIOA->IDR,
			(uint32_t) Buffer_Dest, 4);
  /* USER CODE END 2 */

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

    /* USER CODE BEGIN 3 */
		// Check if DMA transfer completed
		if (transfer_complete) {
			transfer_complete = 0; // Reset flag

			// At this point, you can examine:
			// - Buffer_Dest[0-3]: individual bytes from GPIOA->IDR
			// - gpio_value: reconstructed 32-bit value

			// Increment counter and only toggle pin every TOGGLE_DIVIDER times
			toggle_counter++;
			if (toggle_counter >= TOGGLE_DIVIDER) {
				toggle_counter = 0; // Reset counter
				// Toggle LED to indicate transfer completed (slowed down 100x)
				HAL_GPIO_TogglePin(PC0_GPIO_Port, PC0_Pin);
			}

			// Wait a bit before next transfer
//			HAL_Delay(1000);

			// Start another transfer
			HAL_DMA_Start_IT(&hdma_memtomem_dma1_stream0,
					(uint32_t) &GPIOA->IDR, (uint32_t) Buffer_Dest, 4);
		}
	}
  /* 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 = RCC_HSICALIBRATION_DEFAULT;
  RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
  RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSI;
  RCC_OscInitStruct.PLL.PLLM = 10;
  RCC_OscInitStruct.PLL.PLLN = 150;
  RCC_OscInitStruct.PLL.PLLP = 2;
  RCC_OscInitStruct.PLL.PLLQ = 2;
  RCC_OscInitStruct.PLL.PLLR = 2;
  RCC_OscInitStruct.PLL.PLLRGE = RCC_PLL1VCIRANGE_2;
  RCC_OscInitStruct.PLL.PLLVCOSEL = RCC_PLL1VCOWIDE;
  RCC_OscInitStruct.PLL.PLLFRACN = 0;
  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_4) != HAL_OK)
  {
    Error_Handler();
  }
}

/**
  * Enable DMA controller clock
  * Configure DMA for memory to memory transfers
  *   hdma_memtomem_dma1_stream0
  */
static void MX_DMA_Init(void)
{

  /* DMA controller clock enable */
  __HAL_RCC_DMA1_CLK_ENABLE();

  /* Configure DMA request hdma_memtomem_dma1_stream0 on DMA1_Stream0 */
  hdma_memtomem_dma1_stream0.Instance = DMA1_Stream0;
  hdma_memtomem_dma1_stream0.Init.Request = DMA_REQUEST_MEM2MEM;
  hdma_memtomem_dma1_stream0.Init.Direction = DMA_MEMORY_TO_MEMORY;
  hdma_memtomem_dma1_stream0.Init.PeriphInc = DMA_PINC_ENABLE;
  hdma_memtomem_dma1_stream0.Init.MemInc = DMA_MINC_ENABLE;
  hdma_memtomem_dma1_stream0.Init.PeriphDataAlignment = DMA_PDATAALIGN_BYTE;
  hdma_memtomem_dma1_stream0.Init.MemDataAlignment = DMA_MDATAALIGN_BYTE;
  hdma_memtomem_dma1_stream0.Init.Mode = DMA_NORMAL;
  hdma_memtomem_dma1_stream0.Init.Priority = DMA_PRIORITY_LOW;
  hdma_memtomem_dma1_stream0.Init.FIFOMode = DMA_FIFOMODE_ENABLE;
  hdma_memtomem_dma1_stream0.Init.FIFOThreshold = DMA_FIFO_THRESHOLD_FULL;
  hdma_memtomem_dma1_stream0.Init.MemBurst = DMA_MBURST_SINGLE;
  hdma_memtomem_dma1_stream0.Init.PeriphBurst = DMA_PBURST_SINGLE;
  if (HAL_DMA_Init(&hdma_memtomem_dma1_stream0) != HAL_OK)
  {
    Error_Handler( );
  }

  /* DMA interrupt init */
  /* DMA1_Stream0_IRQn interrupt configuration */
  HAL_NVIC_SetPriority(DMA1_Stream0_IRQn, 0, 0);
  HAL_NVIC_EnableIRQ(DMA1_Stream0_IRQn);

}

/**
  * @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_GPIOC_CLK_ENABLE();

  /*Configure GPIO pin Output Level */
  HAL_GPIO_WritePin(PC0_GPIO_Port, PC0_Pin, GPIO_PIN_RESET);

  /*Configure GPIO pin : PC0_Pin */
  GPIO_InitStruct.Pin = PC0_Pin;
  GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
  HAL_GPIO_Init(PC0_GPIO_Port, &GPIO_InitStruct);

  /* USER CODE BEGIN MX_GPIO_Init_2 */

  /* USER CODE END MX_GPIO_Init_2 */
}

/* USER CODE BEGIN 4 */
void XferCpltCallback(DMA_HandleTypeDef *hdma) {
	// Transfer completed - combine the 4 bytes to a 32-bit value for easier interpretation
	gpio_value = (Buffer_Dest[3] << 24) | (Buffer_Dest[2] << 16)
			| (Buffer_Dest[1] << 8) | Buffer_Dest[0];

	// For debugging: you can examine individual bytes here
	// Buffer_Dest[0] = LSB of GPIOA->IDR (pins PA0-PA7)
	// Buffer_Dest[1] = pins PA8-PA15  
	// Buffer_Dest[2] = pins PA16-PA23 (if available)
	// Buffer_Dest[3] = MSB of GPIOA->IDR (pins PA24-PA31, if available)

	transfer_complete = 1;
	__NOP(); //Line reached only if transfer was successful. Toggle a breakpoint here
}
/* 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 */