习近平出访将为中芬和中美关系绘制蓝图、指明方向

在项目中复制出来的程序，使用时可能有些地方需要修改。
编译环境：WinAVR-20060421+AVRStudio4.12.498ServicePack4
基本思路：每份写到EEPRM的数据，都做三个备份，每个备份的数据都做CRC16校验，只要系统运行中出错，错误地修改了EEPROM数据，
那么根据校验字节就知道哪个备份的数据被修改了，然后用正确的备份覆盖出错的备份，达到数据恢复的目的。
EEPROMSave.h文件：
#defineEepromPageSize 64 //页容量定义
#defineEepromPage0Addr 0x0000 //各个页的其始地址定义
#defineEepromPage1Addr (EepromPage0Addr+EepromPageSize)
#defineEepromPage2Addr (EepromPage1Addr+EepromPageSize)
#defineEepromPage3Addr (EepromPage2Addr+EepromPageSize)
#defineEepromPage4Addr (EepromPage3Addr+EepromPageSize)
#defineEepromPage5Addr (EepromPage4Addr+EepromPageSize)
#defineEepromPage6Addr (EepromPage5Addr+EepromPageSize)
#defineEepromPage7Addr (EepromPage6Addr+EepromPageSize)
#defineVALID 0x01
#defineINVALID 0x00
EEPROMSave.c文件：
unsignedcharEepromReadByte(unsignedchar*address)
{
unsignedchardata;
data=0;
eeprom_busy_wait();
data=eeprom_read_byte(address);
returndata;
}
uint16_tEepromReadWord(uint16_t*address)
{
uint16_tdata;
data=0;
eeprom_busy_wait();
data=eeprom_read_word(address);
returndata;
}
voidEepromWriteByte(unsignedchar*address,unsignedchardata)
{
eeprom_busy_wait();
eeprom_write_byte(address,data);
}
voidEepromWriteWord(unsignedint*address,unsignedintdata)
{
eeprom_busy_wait();
eeprom_write_word(address,data);
}
voidEepromWriteBlock(unsignedchar*buff,unsignedchar*address,unsignedcharn)
{
unsignedchari;
for(i=0;i<n;i++)
{
EepromWriteByte((unsignedchar*)(address+i),*buff);
buff++;
}
}
unsignedcharEepromCheck(unsignedchar*pdata,unsignedcharpacksize)
{
unsignedchari,j;
unsignedintcrc,ref_crc;
crc=0;
ref_crc=0;
for(i=0;i<(packsize-2);i++)
{
crc=crc^((uint16_t)EepromReadByte(pdata)<<8);
for(j=0;j<8;j++)
{
if(crc&0x8000)
{
crc=(crc<<1)^0x1021;
}
else
{
crc=crc<<1;
}
}
pdata++;
}
ref_crc=(uint16_t)EepromReadByte(pdata);
ref_crc=ref_crc<<8;
pdata++;
ref_crc|=(uint16_t)EepromReadByte(pdata);
if(crc==ref_crc)
{
returnVALID;
}
else
{
returnINVALID;
}
}
unsignedcharCheckWriteCRC(unsignedchar*pdata,unsignedcharpacksize)
{
unsignedchari,j;
unsignedintcrc;
crc=0;
for(i=0;i<(packsize-2);i++)
{
crc=crc^((uint16_t)EepromReadByte(pdata)<<8);
for(j=0;j<8;j++)
{
if(crc&0x8000)
{
crc=(crc<<1)^0x1021;
}
else
{
crc=crc<<1;
}
}
pdata++;
}
EepromWriteByte(pdata,(uint8_t)(crc>>8));
pdata++;
EepromWriteByte(pdata,(uint8_t)crc);
pdata++;
if(EepromCheck((pdata-packsize),packsize))
{
returnVALID;
}
else
{
returnINVALID;
}
}
uint8_tCheckAllPage(void)
{
if((EepromCheck((unsignedchar*)EepromPage1Add,EepromPageSize)==VALID)
&&(EepromCheck((unsignedchar*)EepromPage2Add,EepromPageSize)==VALID)
&&(EepromCheck((unsignedchar*)EepromPage3Add,EepromPageSize)==VALID))
{
returnVALID;
}
returnINVALID;
}
uint8_tDataRecover(void)
{
unsignedchari;
unsignedchartemp;
unsignedcharpage;
unsignedintinvalidpage[3];
unsignedintvalidpage;
invalidpage[0]=0;
invalidpage[1]=0;
invalidpage[2]=0;
validpage=0;
temp=0;
page=0;
if(EepromCheck((uint8_t*)EepromPage1Add,EepromPageSize)==VALID)
{
validpage=EepromPage1Add;
}
else
{
invalidpage[page]=EepromPage1Add;
page++;
}
if(EepromCheck((uint8_t*)EepromPage2Add,EepromPageSize)==VALID)
{
validpage=EepromPage2Add;
}
else
{
invalidpage[page]=EepromPage2Add;
page++;
}
if(EepromCheck((uint8_t*)EepromPage3Add,EepromPageSize)==VALID)
{
validpage=EepromPage3Add;
}
else
{
invalidpage[page]=EepromPage3Add;
page++;
}
if(page==3) //三个备份都被破坏了
{
returnINVALID; //数据完全无效了
}
while((page--)>0) //数据恢复
{
for(i=0;i<EepromPageSize;i++)
{
temp=EepromReadByte((uint8_t*)(validpage+i));
EepromWriteByte((uint8_t*)(invalidpage[page]+i),temp);
}
}
if(CheckAllPage()==VALID)
{
returnVALID;
}
returnINVALID;
}
使用方法(三个备份）：
1、定义一个数组：EEPROMData[EepromPageSize-2]，数组定义为EepromPageSize-2是为了给每个备份留2个字节的校验
2、要保存数据时，先把数据放到数组中，然后调用EepromWriteBlock()函数，把这个数组的数据写进EEPROM，三个备份要写三次。
3、写完了之后，调用CheckWriteCRC()函数，该函数会计算出当前备份的CRC16检验数据并写到EEPROM备份的尾部，有多少个备份就要调用多少次。
4、至此，数据的备份工作已经完成。
5、校验数据（一般在复位后运行），执行CheckAllPage()函数，若通过了，则EEPROM数据没有问题，否则要运行DataRecover()函数，对损坏的备份进行修复