text: /**
    ******************************************************************************
    * @file    USB_Device/CustomHID_Standalone/Src/main.c
    * @author  MCD Application Team
    * @brief   USB device Custom HID demo main file
    ******************************************************************************
    * @attention
    *
    * <h2><center>&copy; Copyright(c) 2017 STMicroelectronics International N.V. 
    * All rights reserved.</center></h2>
    *
    * Redistribution and use in source and binary forms, with or without 
    * modification, are permitted, provided that the following conditions are met:
    *
    * 1. Redistribution of source code must retain the above copyright notice, 
    *    this list of conditions and the following disclaimer.
    * 2. Redistributions in binary form must reproduce the above copyright notice,
    *    this list of conditions and the following disclaimer in the documentation
    *    and/or other materials provided with the distribution.
    * 3. Neither the name of STMicroelectronics nor the names of other 
    *    contributors to this software may be used to endorse or promote products 
    *    derived from this software without specific written permission.
    * 4. This software, including modifications and/or derivative works of this 
    *    software, must execute solely and exclusively on microcontroller or
    *    microprocessor devices manufactured by or for STMicroelectronics.
    * 5. Redistribution and use of this software other than as permitted under 
    *    this license is void and will automatically terminate your rights under 
    *    this license. 
    *
    * THIS SOFTWARE IS PROVIDED BY STMICROELECTRONICS AND CONTRIBUTORS "AS IS" 
    * AND ANY EXPRESS, IMPLIED OR STATUTORY WARRANTIES, INCLUDING, BUT NOT 
    * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A 
    * PARTICULAR PURPOSE AND NON-INFRINGEMENT OF THIRD PARTY INTELLECTUAL PROPERTY
    * RIGHTS ARE DISCLAIMED TO THE FULLEST EXTENT PERMITTED BY LAW. IN NO EVENT 
    * SHALL STMICROELECTRONICS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
    * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
    * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, 
    * OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF 
    * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING 
    * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
    * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
    *
    ******************************************************************************
    */
  
  /* Includes ------------------------------------------------------------------*/
  #include "main.h"
  
  /* Private typedef -----------------------------------------------------------*/
  /* Private define ------------------------------------------------------------*/
  /* Private macro -------------------------------------------------------------*/
  /* Private variables ---------------------------------------------------------*/
  USBD_HandleTypeDef USBD_Device;
  extern PCD_HandleTypeDef hpcd;
  /* Private function prototypes -----------------------------------------------*/
  static void SystemClock_Config(void);
  static void Error_Handler(void);
  
  /* Private functions ---------------------------------------------------------*/
  
  /**
    * @brief  Main program
    * @param  None
    * @retval None
    */
  int main(void)
  {
    /* STM32L4xx HAL library initialization:
         - Configure the Flash prefetch
         - Systick timer is configured by default as source of time base, but user 
           can eventually implement his proper time base source (a general purpose 
           timer for example or other time source), keeping in mind that Time base 
           duration should be kept 1ms since PPP_TIMEOUT_VALUEs are defined and 
           handled in milliseconds basis.
         - Set NVIC Group Priority to 4
         - Low Level Initialization
       */
    
    /* Initialize the HAL Library */
    HAL_Init();
    
    /* Configure the system clock to 80 MHz */
    SystemClock_Config();
    
    /* Enable Power Clock*/
    __HAL_RCC_PWR_CLK_ENABLE();
    
    /* enable USB power on Pwrctrl CR2 register */
    HAL_PWREx_EnableVddUSB();
    
    /* Configure LED3 */
    BSP_LED_Init(LED3);
  
    /* Init Device Library */
    USBD_Init(&USBD_Device, &HID_Desc, 0);
    
    /* Add Supported Class */
    USBD_RegisterClass(&USBD_Device, &USBD_CUSTOM_HID);
    
    /* Add Custom HID callbacks */
    USBD_CUSTOM_HID_RegisterInterface(&USBD_Device, &USBD_CustomHID_fops);
    
    /* Start Device Process */
    USBD_Start(&USBD_Device);
  
    /* Run Application (Interrupt mode) */
    while (1)
    {
    }
  }
  
  /**
    * @brief  System Clock Configuration
    *         The system Clock is configured as follow : 
    *
    *         If define USB_USE_LSE_MSI_CLOCK enabled:
    *            System Clock source            = PLL (MSI)
    *            SYSCLK(Hz)                     = 80000000
    *            HCLK(Hz)                       = 80000000
    *            AHB Prescaler                  = 1
    *            APB1 Prescaler                 = 1
    *            APB2 Prescaler                 = 2
    *            MSI Frequency(Hz)              = 4800000
    *            LSE Frequency(Hz)              = 32768
    *            PLL_M                          = 6
    *            PLL_N                          = 40
    *            PLL_P                          = 7
    *            PLL_Q                          = 4
    *            PLL_R                          = 4
    *            Flash Latency(WS)              = 4
    * 
    *         If define USB_USE_HSE_CLOCK enabled:
    *            System Clock source            = PLL (HSE)
    *            SYSCLK(Hz)                     = 80000000
    *            HCLK(Hz)                       = 80000000
    *            AHB Prescaler                  = 1
    *            APB1 Prescaler                 = 1
    *            APB2 Prescaler                 = 2
    *            HSE Frequency(Hz)              = 8000000
    *            PLL_M                          = 1
    *            PLL_N                          = 20
    *            PLL_P                          = 7
    *            PLL_Q                          = 4
    *            PLL_R                          = 2
    *            Flash Latency(WS)              = 4
    * 
    * @param  None
    * @retval None
    */
  static void SystemClock_Config(void)
  {
    RCC_ClkInitTypeDef RCC_ClkInitStruct;
    RCC_OscInitTypeDef RCC_OscInitStruct;
    RCC_PeriphCLKInitTypeDef PeriphClkInitStruct;
  
  #if defined (USB_USE_LSE_MSI_CLOCK)
   
    /* Enable the LSE Oscilator */
    RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_LSE;
    RCC_OscInitStruct.LSEState = RCC_LSE_ON;
    RCC_OscInitStruct.PLL.PLLState        = RCC_PLL_OFF;
    HAL_RCC_OscConfig(&RCC_OscInitStruct);
    
    /* Enable the CSS interrupt in case LSE signal is corrupted or not present */
    HAL_RCCEx_DisableLSECSS();
    
    /* Enable MSI Oscillator and activate PLL with MSI as source */
    RCC_OscInitStruct.OscillatorType      = RCC_OSCILLATORTYPE_MSI;
    RCC_OscInitStruct.MSIState            = RCC_MSI_ON;
    RCC_OscInitStruct.MSICalibrationValue = RCC_MSICALIBRATION_DEFAULT;
    RCC_OscInitStruct.MSIClockRange       = RCC_MSIRANGE_11;
    RCC_OscInitStruct.PLL.PLLState        = RCC_PLL_ON;
    RCC_OscInitStruct.PLL.PLLSource       = RCC_PLLSOURCE_MSI;
    RCC_OscInitStruct.PLL.PLLM            = 6;
    RCC_OscInitStruct.PLL.PLLN            = 40;
    RCC_OscInitStruct.PLL.PLLP            = 7;
    RCC_OscInitStruct.PLL.PLLQ            = 4;
    RCC_OscInitStruct.PLL.PLLR            = 4;
    if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK)
    {
      Error_Handler();
    }
  
    /* Enable MSI Auto-calibration through LSE */
    HAL_RCCEx_EnableMSIPLLMode();
  
    /* Select MSI output as USB clock source */
    PeriphClkInitStruct.PeriphClockSelection = RCC_PERIPHCLK_USB;
    PeriphClkInitStruct.UsbClockSelection = RCC_USBCLKSOURCE_MSI;
    HAL_RCCEx_PeriphCLKConfig(&PeriphClkInitStruct);
  
    /* Select PLL as system clock source and configure the HCLK, PCLK1 and PCLK2 
    clocks dividers */
    RCC_ClkInitStruct.ClockType = (RCC_CLOCKTYPE_SYSCLK | RCC_CLOCKTYPE_HCLK | RCC_CLOCKTYPE_PCLK1 | RCC_CLOCKTYPE_PCLK2);
    RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;
    RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
    RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV1;
    RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV2;
    if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_4) != HAL_OK)
    {
      Error_Handler();
    }
    
  #elif defined (USB_USE_HSE_CLOCK)
    
    /* Enable HSE Oscillator and activate PLL with HSE as source */
    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 = 1;
    RCC_OscInitStruct.PLL.PLLN = 20;
    RCC_OscInitStruct.PLL.PLLR = 2;
    RCC_OscInitStruct.PLL.PLLP = 7;
    RCC_OscInitStruct.PLL.PLLQ = 4;  
    
    if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK)
    {
      Error_Handler();
    }
    
    /* Select PLLSAI output as USB clock source */
    PeriphClkInitStruct.PeriphClockSelection = RCC_PERIPHCLK_USB;
    PeriphClkInitStruct.UsbClockSelection = RCC_USBCLKSOURCE_PLLSAI1;
    PeriphClkInitStruct.PLLSAI1.PLLSAI1N = 24;
    PeriphClkInitStruct.PLLSAI1.PLLSAI1Q = 4; 
    PeriphClkInitStruct.PLLSAI1.PLLSAI1P = 1;
    PeriphClkInitStruct.PLLSAI1.PLLSAI1M = 1;
    PeriphClkInitStruct.PLLSAI1.PLLSAI1Source = RCC_PLLSOURCE_HSE;
    PeriphClkInitStruct.PLLSAI1.PLLSAI1ClockOut= RCC_PLLSAI1_48M2CLK;
    if(HAL_RCCEx_PeriphCLKConfig(&PeriphClkInitStruct)!= HAL_OK)
    {
      Error_Handler();
    }
    
    /* Select PLL as system clock source and configure the HCLK, PCLK1 and PCLK2 
    clocks dividers */
    RCC_ClkInitStruct.ClockType = (RCC_CLOCKTYPE_SYSCLK | RCC_CLOCKTYPE_HCLK | RCC_CLOCKTYPE_PCLK1 | RCC_CLOCKTYPE_PCLK2);
    RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;
    RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV2;
    RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV1;
    RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV2;
    if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_4) != HAL_OK)
    {
      Error_Handler();
    }
    
  #endif /* USB_USE_LSE_MSI_CLOCK */
  }
  
  /**
    * @brief  This function is executed in case of error occurrence.
    * @param  None
    * @retval None
    */
  static void Error_Handler(void)
  {
    /* Turn LED3 on */
    BSP_LED_On(LED3);
  
    while (1)
    {
    }
  }
  
  #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(char *file, uint32_t line)
  {
    /* 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) */
  
    /* Infinite loop */
    while (1)
    {
    }
  }
  #endif
  
  /************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/
  