sst29sf040不是flash吗,为什么我把它当作数据存储器时一掉电数据就会丢失呢？
sst29sf040的A0-A7接74ls373的输出，74373集成在CPLD中，没画出来,A8-A14接AT89C52的P20-P26，而A15-A18接地，因为我用不到那么大的空间，而其片选端CE接AT89C52的P27

void  ByteProgram(uchar data SrcByte,uint Dst)
{
XBYTE[0x0555] = 0xAA;
XBYTE[0x02AA] = 0x55;
XBYTE[0x0555] = 0xA0;
    XBYTE[Dst]   = SrcByte;
    wait(1,9);//等待25us
}

int Erase_One_Sector(uint Dst)
{

        /*  Issue the Sector Erase command to 39SF040   */

        XBYTE[0x0555] = 0xAA; /* set up address to be 555h    */
                             /* write data 0xAA to the address     */
        XBYTE[0x02AA] = 0x55; /* set up address to be 2AAh    */
                             /* write data 0x55 to the address     */
        XBYTE[0x0555] = 0x80; /* set up address to be 555h    */
                             /* write data 0x80 to the address     */
        XBYTE[0x0555] = 0xAA; /* set up address to be 555h    */
                             /* write data 0xAA to the address     */
        XBYTE[0x02AA] = 0x55; /* set up address to be 2AAh    */
                             /* write data 0x55 to the address     */
        XBYTE[Dst]   = 0x20; /* set up starting address to be erased */
                             /* write data 0x30 to the address     */
        wait(85,134);        /* check DATABOOK for the most  */
                             /* accurate value -- Tse        */
}

uchar ByteRead(uint addr)
{
uchar GetData;
GetData = XBYTE[addr];
return(GetData);
}
void sst_save()//用于保存易丢失数据
{
  uchar i;
Erase_One_Sector(128);
     for(i=0;i<4;i++)
   {  
          
     ByteProgram(syn[2*i+1],0x0080+i);
     syn[2*i+1]=ByteRead(0x0080+i);
    
   }
}
void main()
{
   sst_save();我 在程序中改变syn 的值未写出，为什么我一断电，syn 的值还是原来的赋的初值呢？
}

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