STM3完成FLASH的读写操作

读取操作：
- 读取Flash数据的过程是将要读取的Flash地址转换为指针，然后获取该指针指向的数据。
- 读取操作通常不需要解锁Flash，因为读取数据不会对Flash造成任何影响。
写入操作：
- 写入Flash数据需要先解锁Flash，然后擦除目标扇区，最后写入数据。
- Flash的写入操作是以块（扇区）为单位进行的，因此在写入新数据之前，必须先擦除目标扇区。
- 写入数据时，需要确保指定的地址没有被写保护，否则写入操作将失败。

四、注意事项

擦写次数限制：Flash的擦写次数是有限制的，通常为10万次至100万次。因此，在编程时应尽量减少对Flash的频繁写操作。
读写保护：STM32提供了读写保护功能，以防止数据被意外修改。这可以通过设置选项字节来实现。
编程顺序：在进行Flash编程时，需要遵循一定的编程顺序，如先解锁Flash、再擦除目标扇区、最后写入数据等。

五、应用场景

程序代码存储：Flash存储器的主要应用场景之一是存储程序代码。编译后的程序代码被烧录到Flash中，以便在微控制器上运行。
数据存储：除了程序代码外，Flash还可以用于存储一些需要长期保存的数据，如配置参数、用户设置等。
固件更新：在嵌入式系统中，固件更新是一个常见的需求。通过Flash存储器，可以实现固件的在线更新（In-Circuit Programming，ICP）或在程序中编程（In-Application Programming，IAP）。

二、工程建立

（1）建立新工程

打开cubemx，点击new project建立文件(笔者选用的是STM32C8T6芯片）

（2）配置RCC

（3）配置SYS

（4）配置pc13为输出引脚

（5）配置时钟

（6）完成相关基础配置

（7）完成配置后生成keil文件

三、代码编写

打开生成的keil文件加入相应代码

（1）flash.c

/*
 * flash.c
 *
 * Created: 2018-01-29
 * Author: zhanglifu
 */
 
/*********************************************************************/
//                        头文件
/*********************************************************************/
#include "flash.h"
 
 
// 不检查的写入
// WriteAddr:起始地址
// pBuffer:  数据指针
// NumToWrite:字节数数
void FlashWriteNoCheck( uint32_t WriteAddr,uint8_t *pBuffer,uint16_t NumToWrite )
{
    uint16_t i;
 
    for( i=0; i<NumToWrite; i+=4 )
    {
        while( HAL_OK != HAL_FLASH_Program(FLASH_TYPEPROGRAM_WORD, WriteAddr+i,*(uint32_t *)(pBuffer+i) ) );
    }
 
}
 
extern void FLASH_PageErase(uint32_t PageAddress);
void FlashWriteBuff( const uint32_t destination_address, uint8_t *const buffer,uint32_t length )
{
    uint16_t i;
    uint8_t FlashBuff[FMC_SECTOR_SIZE];
    uint32_t StartAddress = destination_address - destination_address%FMC_SECTOR_SIZE;
    uint16_t Offset = destination_address - StartAddress;
    uint8_t *pBuf = buffer;
    uint32_t remaindNum = length;
 
    HAL_StatusTypeDef status = HAL_ERROR;
 
    // 地址检查
    if( (destination_address < FMC_FLASH_BASE) || ( destination_address + length >= FMC_FLASH_END) || (length <= 0) )
        return;
 
    HAL_FLASH_Unlock();	// 解锁
    do
    {
        // 读出一页数据
        for(i=0; i < FMC_SECTOR_SIZE; i += 4 )
            *(uint32_t *)(FlashBuff+i) = *(uint32_t *)(StartAddress+i);
 
        // 修改要改入的数据
        for ( i=0; (i+Offset)<FMC_SECTOR_SIZE && i< remaindNum; i++ )
            *(FlashBuff+Offset+i) = *(pBuf+i);
 
 
        // 擦除一ROW数据
        FLASH_PageErase( StartAddress );
 
        // HAL库 FLASH_PageErase有BUFF,要加上下面三行代码
        while( status != HAL_OK )
            status = FLASH_WaitForLastOperation(FLASH_TIMEOUT_VALUE);
        CLEAR_BIT(FLASH->CR, FLASH_CR_PER);
 
        // 写入数据
        FlashWriteNoCheck( StartAddress,FlashBuff,FMC_SECTOR_SIZE );
 
        // 为下一页做准备
        StartAddress +=  FMC_SECTOR_SIZE;
        remaindNum -= i;
        pBuf += i;
        Offset = 0;
 
    } while( remaindNum > 0 );
 
    HAL_FLASH_Lock();  // 上锁
		
}
 
 
 
// 从FLASH中读指定长度数据
void FlashReadBuff(const uint32_t source_address,uint8_t *const buffer,uint16_t length)
{
    uint16_t i;
    uint8_t Offset = 0;
    uint32_t StartAddress = source_address;
    uint16_t data;
 
    // 地址检测
    if( source_address + length > FMC_FLASH_END ) return;
 
    // 如果没有对16齐
    if( source_address & 1 )
    {
        Offset = 1;
        StartAddress = source_address-1;
    }
 
    // flash的操作要求16对齐 最小读写操作16个比特
    if ( Offset )
    {
        data = *(uint16_t *)(StartAddress);
        buffer[0] = data >> 8;
        StartAddress += 2;
    }
 
    for ( i = 0; i < (length-Offset); i += 2)
    {
        data = *(uint16_t *)(StartAddress+i);
        buffer[i+Offset] = (data & 0xFF);
        if ( (i+Offset) < (length - 1) )
            buffer[i + Offset + 1] = (data >> 8);
    }
 
}

（2）flash.h

/*
 * flash.h
 *
 * Created: 2016-04-22
 * Author: zhanglifu
 */
#ifndef _flash_H_
#define _flash_H_
 
 
#include "stm32f1xx_hal.h"
 
 
/*********************************************************************/
//                        变量定义
/*********************************************************************/
//-- 用途划分
// 0x0800FC00-0x0800FFFF -- 使用最后4k 个字节用来存放电机信息
#define FMC_FLASH_BASE      0x08000000 	// FLASH的起始地址
#define APP_MAX_SIZE        0x00010000  // 
 
 
#define FMC_FLASH_END        0x08010000  // FLASH的结束地址 256
#define DEVICE_INFO_ADDRESS  0x0800C000  //（STM32_FLASH_END - DEVICE_INFO_SIZE）   // 设备信息起始地址
#define DEVICE_LOG_ADDRESS   0x0800E000  //（STM32_FLASH_END - 2*DEVICE_INFO_SIZE） // 设备日志起始地址
 
 
 
#define FMC_FLASH_SIZE 64			          // 定义Flash大小，单位KB
 
 
#if FMC_FLASH_SIZE < 256
#define FMC_SECTOR_SIZE 1024            // 字节
#define MOD_SECTOR_SIZE 0X3FF
#define PAGE_COUNT_BY16 512
#else
#define FMC_SECTOR_SIZE	2048
#define MOD_SECTOR_SIZE 0X7FF
#define PAGE_COUNT_BY16 1024
#endif
 
 
 
 
 
/*********************************************************************/
//                        函数声明
/*********************************************************************/
void FlashWriteBuff( const uint32_t destination_address, uint8_t *const buffer,uint32_t length );
void FlashReadBuff(const uint32_t source_address,uint8_t *const buffer,uint16_t length);
 
 
 
 
#endif

（3）main.c

/* USER CODE BEGIN Header */
/**
  ******************************************************************************
  * @file           : main.c
  * @brief          : Main program body
  ******************************************************************************
  ** This notice applies to any and all portions of this file
  * that are not between comment pairs USER CODE BEGIN and
  * USER CODE END. Other portions of this file, whether 
  * inserted by the user or by software development tools
  * are owned by their respective copyright owners.
  *
  * COPYRIGHT(c) 2019 STMicroelectronics
  *
  * Redistribution and use in source and binary forms, with or without modification,
  * are permitted provided that the following conditions are met:
  *   1. Redistributions 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 its contributors
  *      may be used to endorse or promote products derived from this software
  *      without specific prior written permission.
  *
  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER 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.
  *
  ******************************************************************************
  */
/* USER CODE END Header */
 
/* Includes ------------------------------------------------------------------*/
#include "main.h"
#include "gpio.h"
 
/* Private includes ----------------------------------------------------------*/
/* USER CODE BEGIN Includes */
#include "flash.h"
/* 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);
/* USER CODE BEGIN PFP */
 
/* USER CODE END PFP */
 
/* Private user code ---------------------------------------------------------*/
/* USER CODE BEGIN 0 */
uint8_t FlashWBuff [255];
uint8_t FlashRBuff [255];
/* USER CODE END 0 */
 
/**
  * @brief  The application entry point.
  * @retval int
  */
int main(void)
{
  /* USER CODE BEGIN 1 */
	uint8_t i;
	uint8_t FlashTest[] = "Hello This is xingyejin Flash Test DEMO";
  /* 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 */
	FlashWriteBuff( DEVICE_INFO_ADDRESS, FlashTest,sizeof(FlashTest) );        // 写入数据到Flash
	
	for(i=0;i<255;i++)
    FlashWBuff[i] = i;
	
    FlashWriteBuff( DEVICE_INFO_ADDRESS + sizeof(FlashTest), FlashWBuff,255 );  // 写入数据到Flash
    FlashReadBuff(  DEVICE_INFO_ADDRESS + sizeof(FlashTest),FlashRBuff,255  );  // 从Flash中读取数
  /* USER CODE END SysInit */
 
  /* Initialize all configured peripherals */
  MX_GPIO_Init();
  /* USER CODE BEGIN 2 */
	
	
 
  /* USER CODE END 2 */
 
  /* Infinite loop */
  /* USER CODE BEGIN WHILE */
  while (1)
  {
    /* 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 CPU, AHB and APB busses clocks 
  */
  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 busses 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 */
 
/* 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 */
 
  /* 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,
     tex: 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****/