Teach you how to use Hal library to get started -- become a lighting master

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Preface

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Basic knowledge of

The clock

• HSI： Internal high speed clock
• LSI： Internal low speed clock
• HSE： External high-speed clock
• LSE： External low speed clock

Because the internal clock is easily affected by the chip temperature , So the accuracy is not very good . Therefore, the external clock is generally used .

GPIO I / O mode of

• Push pull output ：
  The push-pull structure consists of two MOS The tubes are connected in a complementary and symmetrical manner , At any time, one of the triodes is always on , The other triode is off . Such as ① Shown , The interior consists of a P-MOS Tube and a N-MOS Tube composition , Two MOS The grid of the tube （ Gate, G） Receive
  Left “ Output control ” , Drain electrode （ Drain, D） Connected to external output , P-MOS The source of the tube （ Source, S） Receive VDD（ 3.3V）,N-MOS The source of the tube is connected to Vss（ 0V）.
  MOS The tube is used as a switch ,“ Output control ” To two MOS Apply a certain voltage to the tube grid , P-MOS Conduction between the source and drain of the tube ,VDD after P-MOS Tubular S->G->D Output , N-MOS The tube is in a high resistance state （ The resistance is very high , Approximate open circuit ）, The overall external is high level ;“ Output control ” Cancel to two MOS Apply voltage to the tube grid , P-MOS Tube source and grid cut-off ,P-MOS The tube is in a high resistance state , N-MOS The source and drain of the tube are connected , The overall external is low level .
  Push pull mode , Give Way “ Output control ” Change into VDD/Vss Output , Increase the output current , The driving ability of the output pin is improved , Improve
  The load capacity of the circuit and the action speed of the switch .

• Open drain output
  In open drain mode ,“ Output control ” Will not control P-MOS tube , “ Output control ” Only to N-MOS Apply a certain voltage to the tube grid , Two
  MOS All tubes are in the cut-off state , The two drains are suspended , It's called open drain .“ Output control ” Cancel the applied voltage of the grid , PMOS The tube is still in the high resistance state , N-MOS The pipe is open , The overall external is low level .
  

• Multiplexing push pull output / Reuse open drain output
  GPIO In addition to being a general-purpose input / The output pin uses an external pin , It can also be used as an on-chip peripheral （ USART、 I2C、 SPI etc. ） Dedicated pin , That is, one pin can be used for many purposes , But one pin can only use one of the multiplexing functions at the same time .
  When the pin is set to the multiplexing function , The multiplexed push-pull output mode or multiplexed open drain output mode can be selected , Set to multiplex open drain output mode
  when , It needs to be connected with pull resistance .

• Pull up input
  Such as ② Shown , VDD Through the switch 、 Pull up resistance , Connect external I/O Pin . When the switch is closed , external I/O When there is no input signal , The default input is high .
  The typical application of this mode is the external key , When no key is pressed , MCU The pin of is the determined high level , When the key is pressed , The pin level is pulled to low level .

• Drop down input
  Such as ② Shown , Vss Through the switch 、 Pull down resistance , Connect external I/O Pin . When the switch is closed , external I/O When there is no input signal , The default input is low .

• Floating input
  Such as ② Shown , Two up / The pull-down resistance switches are disconnected , Neither pull-up nor pull-down , I/O The pins are connected directly TTL Schottky trigger , here I/O The pin is floating , The reading level is uncertain , What level is the external signal , MCU The pin inputs what level . MCU
  Reset after power on , The default is floating input mode .

• Analog input
  Such as ② Shown , Two up / The pull-down resistance switches are disconnected , meanwhile TTL The Schottky trigger switch is also off , The pin signal is directly connected to the analog input , Realize the acquisition of external signals .

CubeMX To configure

First step , Set the clock


The second step , To configure GPIO Pin
First, check the schematic diagram , find LED And the buttons

Keil Programming

The main program

main.c

/* USER CODE BEGIN Header */
/** ****************************************************************************** * @file : main.c * @brief : Main program body ****************************************************************************** * @attention * * Copyright (c) 2022 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 ---------------------------------------------------------*/

/* USER CODE BEGIN PV */

/* USER CODE END PV */

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

/* 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();// System clock configuration 

  /* USER CODE BEGIN SysInit */

  /* USER CODE END SysInit */

  /* Initialize all configured peripherals */
  MX_GPIO_Init(); //GPIO initialization 
  /* USER CODE BEGIN 2 */

  /* USER CODE END 2 */

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

    /* USER CODE BEGIN 3 */
      while(1){
    
          if(GPIO_PIN_RESET==HAL_GPIO_ReadPin(GPIOA,GPIO_PIN_0)){
    
                HAL_Delay(8);// Delay , Eliminate key jitter 
              if(GPIO_PIN_RESET==HAL_GPIO_ReadPin(GPIOA,GPIO_PIN_0)){
     // still 0, It means pressing 
                  HAL_GPIO_WritePin(GPIOA,GPIO_PIN_1,GPIO_PIN_RESET);// Light on 
              }else{
    
                  HAL_GPIO_WritePin(GPIOA,GPIO_PIN_1,GPIO_PIN_SET);// The light goes out 
              }
          }
      }
  }
  /* 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();
  }
}

/** * @brief GPIO Initialization Function * @param None * @retval None */
static void MX_GPIO_Init(void)
{
    
  GPIO_InitTypeDef GPIO_InitStruct = {
    0};

  /* GPIO Ports Clock Enable */
  __HAL_RCC_GPIOD_CLK_ENABLE();
  __HAL_RCC_GPIOA_CLK_ENABLE();

  /*Configure GPIO pin Output Level */
  HAL_GPIO_WritePin(GPIOA, GPIO_PIN_1, GPIO_PIN_RESET);

  /*Configure GPIO pin : PA0 */
  GPIO_InitStruct.Pin = GPIO_PIN_0;
  GPIO_InitStruct.Mode = GPIO_MODE_INPUT;  
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);

  /*Configure GPIO pin : PA1 */
  GPIO_InitStruct.Pin = GPIO_PIN_1;
  GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;  // Push pull output 
  GPIO_InitStruct.Pull = GPIO_PULLUP;   // Pull up 
  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
  HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);

}

/* 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 */

Experimental phenomena

No problem