一个经典的指针交换数值函数：

#include <stdio.h>void interchange(int *u,int *v);
void interchange(int *u,int *v)
{int temp;temp=*v;*v=*u;*u=temp;
}int main()
{int x=5,y=10;printf("before swap value x:%d value y:%d\n",x,y);interchange(&x,&y);printf("after swap value x:%d value y:%d\n",x,y);return 0;
}

输出结果

before swap value x:5 value y:10
after swap value x:10 value y:5

//计算所要擦除 的页数
static u32 FLASH_PagesMask(vu32 Size)
{u32 pagenumber = 0x0;u32 size = Size;if ((size % FLASH_PAGE_SIZE) != 0){pagenumber = (size / FLASH_PAGE_SIZE) + 1;}else{pagenumber = size / FLASH_PAGE_SIZE;}return pagenumber;
}
/*flash的写函数：输入： u32 StarAddr :FLASH起始地址u32 p_data	 :待写入数据指针u32 size	 :写入数据的数量输出：0			 :写入成功非0			 :出错注意：输入数据一定是u32 的指针，即数据一定是按照4字节对齐写入的。所以：size也是u32的个数（字节数的4分之一）
*/
bool flash_write(u32 StartAddr,u32 *p_data,u32 size_u32)
{volatile FLASH_Status FLASHStatus;			 //FLASH状态u32 EndAddr	= StartAddr + 4*size_u32;		   	 //末地址vu32 NbrOfPage = 0;u32 EraseCounter = 0x0, Address = 0x0;int MemoryProgramStatus = 1,i;FLASH_Unlock();									 //FLASH解锁NbrOfPage = FLASH_PagesMask(size_u32*4);	//有多少个页被擦除	//清除所有已有标志FLASH_ClearFlag(FLASH_FLAG_BSY | FLASH_FLAG_EOP | FLASH_FLAG_PGERR | FLASH_FLAG_WRPRTERR);//擦除FLASHStatus = FLASH_COMPLETE; for(EraseCounter = 0;(EraseCounter<NbrOfPage)&&(FLASHStatus==FLASH_COMPLETE);EraseCounter++){FLASHStatus = FLASH_ErasePage(StartAddr+(FLASH_PAGE_SIZE*EraseCounter));}//写入FLASHAddress = StartAddr;for(i = 0 ;(Address < EndAddr) && (FLASHStatus==FLASH_COMPLETE);Address += 4){FLASHStatus = FLASH_ProgramWord(Address,p_data[i++]);	}//校验写入的数据Address = StartAddr;for(i = 0 ;(Address < EndAddr) && (MemoryProgramStatus != 0);Address += 4){if((*(vu32*)Address != p_data[i++])){MemoryProgramStatus = 0;return false;}}return true;	
}/*flash的读函数：输入： u32 StarAddr :FLASH起始地址u32 p_data	 :读出数据预存地址指针u32 size	 :读出数据的数量*/ 
bool flash_read(u32 StartAddr,u32 *p_data,u32 size_u32)
{u32 EndAddr = StartAddr + 4*size_u32;	//flash末地址int MemoryProgramStatus = 1;u32 Address = 0x0;int i = 0;Address = StartAddr;//读取flashwhile( (Address < EndAddr) && (MemoryProgramStatus != 0) ){p_data[i++]=(*(vu32*) Address);Address += 4;	}return true;
}