static关键字在定义接口初始化结构体的用处是什么？

/* USER CODE BEGIN PV */

static GPIO_InitTypeDef  GPIO_InitStruct;



/* 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 */



/* USER CODE END 0 */



/**

  * [url=home.php?mod=space&uid=247401]@brief[/url]  The application entry point.

  * @retval int

  */

int main(void)

{

  /* USER CODE BEGIN 1 */

  /* STM32G4xx 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

     */

  /* 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 */

  /* USER CODE BEGIN 2 */



   /* -1- Enable GPIO Clock (to be able to program the configuration registers) */

  LED2_GPIO_CLK_ENABLE();



  /* -2- Configure IO in output push-pull mode to drive external LEDs */

  GPIO_InitStruct.Mode  = GPIO_MODE_OUTPUT_PP;

  GPIO_InitStruct.Pull  = GPIO_PULLUP;

  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_HIGH;



  GPIO_InitStruct.Pin = LED2_PIN;

  HAL_GPIO_Init(LED2_GPIO_PORT, &GPIO_InitStruct);