text: /* USER CODE BEGIN Header */
  /**
    ******************************************************************************
    * @file           : main.c
    * @brief          : Main program body
    ******************************************************************************
    * @attention
    *
    * SPI Master and Slave
    *
    ******************************************************************************
    */
  /* USER CODE END Header */
  /* Includes ------------------------------------------------------------------*/
  #include "main.h"
  #include "spi.h"
  #include "usart.h"
  #include "gpio.h"
  
  /* Private includes ----------------------------------------------------------*/
  /* USER CODE BEGIN Includes */
  #include "stdio.h"
  /* USER CODE END Includes */
  
  /* Private typedef -----------------------------------------------------------*/
  /* USER CODE BEGIN PTD */
  
  /* USER CODE END PTD */
  
  /* Private define ------------------------------------------------------------*/
  /* USER CODE BEGIN PD */
  
  #define SLAVE_INSTRUCTION_WAIT 0x00
  #define SLAVE_INSTRUCTION_FINGERPRINT 0x01
  #define SLAVE_INSTRUCTION_RECEIVING 0xff
  
  #define SLAVE_FINGERPRINT 0xdeadbeef
  
  /* USER CODE END PD */
  
  /* Private macro -------------------------------------------------------------*/
  /* USER CODE BEGIN PM */
  
  /* USER CODE END PM */
  
  /* Private variables ---------------------------------------------------------*/
  
  /* USER CODE BEGIN PV */
  
  uint8_t slave_tx_buffer[32];
  uint8_t slave_receive_byte;
  
  uint8_t master_tx_buffer[32];
  uint8_t master_rx_buffer[32];
  
  uint8_t slave_instruction = 0;
  
  /* USER CODE END PV */
  
  /* Private function prototypes -----------------------------------------------*/
  void SystemClock_Config(void);
  /* USER CODE BEGIN PFP */
  
  /* USER CODE END PFP */
  
  /* Private user code ---------------------------------------------------------*/
  /* USER CODE BEGIN 0 */
  
  // Send printf to uart1
  int _write(int fd, char* ptr, int len) {
    HAL_StatusTypeDef hstatus;
  
    if (fd == 1 || fd == 2) {
      hstatus = HAL_UART_Transmit(&huart1, (uint8_t *) ptr, len, HAL_MAX_DELAY);
      if (hstatus == HAL_OK)
        return len;
      else
        return -1;
    }
    return -1;
  }
  
  void HAL_GPIO_EXTI_Callback(uint16_t GPIO_Pin) {
  
  	if (GPIO_Pin == BTN_Pin) {
  		if (HAL_GPIO_ReadPin(BTN_GPIO_Port, BTN_Pin) == GPIO_PIN_SET) {
  			DBG("BTN Release");
  		} else {
  			DBG("BTN Push");
  		}
  	} else if (GPIO_Pin == SPI2_SS_Pin) {
  		if (HAL_GPIO_ReadPin(SPI2_SS_GPIO_Port, SPI2_SS_Pin) == GPIO_PIN_RESET) {
  			DBG("SPI2 SS Selected");
  			HAL_SPI_Receive_IT(&hspi2, &slave_receive_byte, 1);
  		} else {
  			DBG("SPI2 SS Done");
  			HAL_SPI_Abort(&hspi2);
  			slave_instruction = SLAVE_INSTRUCTION_WAIT;
  		}
  	}
  
  }
  
  void HAL_SPI_RxCpltCallback(SPI_HandleTypeDef *hspi) {
  	DBG("RXCB - received 0x%02x", slave_receive_byte);
  
  	switch (slave_instruction) {
  
  	case SLAVE_INSTRUCTION_WAIT:
  		slave_instruction = slave_receive_byte;
  		HAL_SPI_Receive_IT(&hspi2, &slave_receive_byte, 1);
  		break;
  
  	case SLAVE_INSTRUCTION_FINGERPRINT:
  		slave_instruction = SLAVE_INSTRUCTION_RECEIVING;
  		slave_tx_buffer[0] = (SLAVE_FINGERPRINT & 0xff000000) >> 24;
  		slave_tx_buffer[1] = (SLAVE_FINGERPRINT & 0x00ff0000) >> 16;
  		slave_tx_buffer[2] = (SLAVE_FINGERPRINT & 0x0000ff00) >> 8;
  		slave_tx_buffer[3] = (SLAVE_FINGERPRINT & 0x000000ff);
  		HAL_SPI_Transmit_IT(&hspi2, &slave_tx_buffer[0], 5);
  		break;
  
  	case SLAVE_INSTRUCTION_RECEIVING:
  		break;
  //	default:
  //		DBG("Unknown SPI instruction 0x%02x", slave_receive_byte);
  //		slave_instruction = SLAVE_INSTRUCTION_WAIT;
  //		HAL_SPI_Receive_IT(&hspi2, &slave_receive_byte, 1);
  	}
  
  
  }
  
  void HAL_SPI_TxCpltCallback(SPI_HandleTypeDef *hspi) {
  	DBG("TXCB");
  
  	HAL_SPI_Receive_IT(&hspi2, &slave_receive_byte, 1);
  }
  
  void HAL_SPI_TxRxCpltCallback(SPI_HandleTypeDef *hspi) {
  	DBG("TXRXCB");
  }
  
  /* 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_SPI1_Init();
    MX_SPI2_Init();
    MX_USART1_UART_Init();
    /* USER CODE BEGIN 2 */
  
    /* USER CODE END 2 */
  
    /* Infinite loop */
    /* USER CODE BEGIN WHILE */
  
    uint32_t now = 0, last_tick = 0, last_blink = 0, last_spi = 0;;
  
    while (1)
    {
  
  	  now = HAL_GetTick();
  
  	  if (now - last_blink >= 500) {
  		  HAL_GPIO_TogglePin(LED_GPIO_Port, LED_Pin);
  		  last_blink = now;
  	  }
  
  	  if (now - last_tick >= 1000) {
  		  DBG("Tick %lu", now / 1000);
  		  last_tick = now;
  	  }
  
  	  if (now - last_spi >= 2000) {
  
  		  DBG("Checking slave fingerprint");
  		  //memcpy(&master_tx_buffer[0], 0, sizeof(master_tx_buffer));
  		  master_tx_buffer[0] = SLAVE_INSTRUCTION_FINGERPRINT;
  		  HAL_GPIO_WritePin(SPI1_SS_GPIO_Port, SPI1_SS_Pin, GPIO_PIN_RESET);
  		  HAL_SPI_Transmit(&hspi1, &master_tx_buffer[0], 1, HAL_MAX_DELAY);
  		  HAL_SPI_Receive(&hspi1, &master_rx_buffer[0], 5, HAL_MAX_DELAY);
  		  //HAL_SPI_TransmitReceive(&hspi1, &master_tx_buffer[0], &master_rx_buffer[0], 5, HAL_MAX_DELAY);
  		  HAL_GPIO_WritePin(SPI1_SS_GPIO_Port, SPI1_SS_Pin, GPIO_PIN_SET);
  
  		  DBG("Got 0x%02x 0x%02x 0x%02x 0x%02x 0x%02x", master_rx_buffer[0], master_rx_buffer[1], master_rx_buffer[2], master_rx_buffer[3], master_rx_buffer[4]);
  
  		  last_spi = now;
  	  }
  
  
      /* 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};
  
    /** Configure the main internal regulator output voltage
    */
    __HAL_RCC_PWR_CLK_ENABLE();
    __HAL_PWR_VOLTAGESCALING_CONFIG(PWR_REGULATOR_VOLTAGE_SCALE1);
    /** 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.PLL.PLLState = RCC_PLL_ON;
    RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSE;
    RCC_OscInitStruct.PLL.PLLM = 25;
    RCC_OscInitStruct.PLL.PLLN = 192;
    RCC_OscInitStruct.PLL.PLLP = RCC_PLLP_DIV2;
    RCC_OscInitStruct.PLL.PLLQ = 4;
    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_3) != HAL_OK)
    {
      Error_Handler();
    }
  }
  
  /* 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.
    * @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 */
  
  /************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/
  