/* 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"
#include "dma.h"
#include "spi.h"
#include "usart.h"
#include "gpio.h"

/* Private includes ----------------------------------------------------------*/
/* USER CODE BEGIN Includes */
#include "stdio.h"
#include "string.h"
/* USER CODE END Includes */

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

/* USER CODE END PTD */

/* Private define ------------------------------------------------------------*/
/* USER CODE BEGIN PD */
#define PL_PIN     GPIO_PIN_0
#define PL_PORT    GPIOB
#define CE_PIN     GPIO_PIN_1
#define CE_PORT    GPIOB
/* USER CODE END PD */

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

/* USER CODE END PM */

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

/* USER CODE BEGIN PV */

/* USER CODE END PV */

/* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);
/* USER CODE BEGIN PFP */
uint8_t read74HC165(void);
uint8_t read74HC165_SPI(void);
uint16_t readTwo74HC165_SPI(void);
void printBinary(uint8_t data, char* buffer, size_t size);
void printBinary16(uint16_t value);
/* 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();

  /* USER CODE BEGIN SysInit */

  /* USER CODE END SysInit */

  /* Initialize all configured peripherals */
  MX_GPIO_Init();
  MX_DMA_Init();
  MX_USART1_UART_Init();
  MX_SPI1_Init();
  /* USER CODE BEGIN 2 */

  /* USER CODE END 2 */

  /* Infinite loop */
  /* USER CODE BEGIN WHILE */
  while (1)
  {
	  // Read data from 74HC165
	  //uint8_t inputData = read74HC165_SPI();

	  // Print data to UART in binary format
	  //char buffer[20]; // Sufficient buffer size to hold the binary string
	  //printBinary(inputData, buffer, sizeof(buffer));

	  uint16_t inputData = readTwo74HC165_SPI();
	  printBinary16(inputData);
	  //HAL_UART_Transmit(&huart1, (uint8_t*)buffer, strlen(buffer), HAL_MAX_DELAY);

	  //HAL_Delay(1000);
    /* 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};

  /** Initializes the RCC Oscillators according to the specified parameters
  * in the RCC_OscInitTypeDef structure.
  */
  RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSE;
  RCC_OscInitStruct.HSEState = RCC_HSE_ON;
  RCC_OscInitStruct.HSEPredivValue = RCC_HSE_PREDIV_DIV1;
  RCC_OscInitStruct.HSIState = RCC_HSI_ON;
  RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
  RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSE;
  RCC_OscInitStruct.PLL.PLLMUL = RCC_PLL_MUL9;
  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_PLLCLK;
  RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
  RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV2;
  RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1;

  if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_2) != HAL_OK)
  {
    Error_Handler();
  }
}

/* USER CODE BEGIN 4 */
uint8_t read74HC165(void) {
    uint8_t data = 0;

    // Load data from parallel input pins
    HAL_GPIO_WritePin(GPIOB, GPIO_PIN_1, RESET);
    HAL_Delay(1);
    HAL_GPIO_WritePin(GPIOB, GPIO_PIN_1, SET);
    HAL_Delay(1);

    // Read 8 bits from the shift register
    for (int i = 0; i < 8; i++) {
    	data |= HAL_GPIO_ReadPin(GPIOA, GPIO_PIN_6) << (7 - i);

    	HAL_GPIO_WritePin(GPIOB, GPIO_PIN_0, SET);
        HAL_GPIO_WritePin(GPIOB, GPIO_PIN_0, RESET);
    }

    return data;
}

uint8_t read74HC165_SPI(void) {
    uint8_t data = 0;

    // Load data from parallel input pins
    HAL_GPIO_WritePin(PL_PORT, PL_PIN, GPIO_PIN_RESET);
    HAL_Delay(1); // Small delay for stability
    HAL_GPIO_WritePin(PL_PORT, PL_PIN, GPIO_PIN_SET);
    HAL_Delay(1); // Small delay for stability

    // Enable the 74HC165
    HAL_GPIO_WritePin(CE_PORT, CE_PIN, GPIO_PIN_RESET);

    // Receive 8 bits from the shift register using SPI
    HAL_SPI_Receive(&hspi1, &data, 1, HAL_MAX_DELAY);

    // Disable the 74HC165
    HAL_GPIO_WritePin(CE_PORT, CE_PIN, GPIO_PIN_SET);

    return data;
}

uint16_t readTwo74HC165_SPI(void) {
    uint8_t data[2] = {0};
    uint8_t dummy = 0xFF;  // Dummy data to generate clock pulses

    // Load data from parallel input pins
    HAL_GPIO_WritePin(PL_PORT, PL_PIN, GPIO_PIN_RESET);
    HAL_Delay(1); // Small delay for stability
    HAL_GPIO_WritePin(PL_PORT, PL_PIN, GPIO_PIN_SET);
    HAL_Delay(1); // Small delay for stability

    // Enable the 74HC165
    HAL_GPIO_WritePin(CE_PORT, CE_PIN, GPIO_PIN_RESET);

    // Send dummy data and receive 16 bits from the shift registers using SPI
    if (HAL_SPI_TransmitReceive(&hspi1, &dummy, data, 2, HAL_MAX_DELAY) != HAL_OK) {
        // Communication Error
        Error_Handler();
    }

    // Disable the 74HC165
    HAL_GPIO_WritePin(CE_PORT, CE_PIN, GPIO_PIN_SET);

    // Combine the two bytes into a single 16-bit value
    uint16_t result = (data[0] << 8) | data[1];
    return result;
}

void printBinary(uint8_t data, char* buffer, size_t size) {
	// Ensure buffer size is sufficient
	    if (size < 12) { // "Data: 0b" + 8 bits + "\r\n" + null terminator
	        return;
	    }

	    snprintf(buffer, size, "Data: 0b");
	    for (int i = 7; i >= 0; i--) {
	        snprintf(buffer + strlen(buffer), size - strlen(buffer), "%d", (data & (1 << i)) ? 1 : 0);
	    }
	    strcat(buffer, "\r\n");  // Use strcat to append "\r\n"
}

void printBinary16(uint16_t value) {
    char buffer[20] = {0};  // Increased buffer size to accommodate binary string and newline characters
    for (int i = 0; i < 16; i++) {
        buffer[15 - i] = (value & (1 << i)) ? '1' : '0';
    }
    buffer[16] = '\r';
    buffer[17] = '\n';
    HAL_UART_Transmit(&huart1, (uint8_t*)buffer, 18, HAL_MAX_DELAY);
}

/* 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.
  * @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 */