各位大哥sst29sf040当数据存储器的时候有限制吗？

只看该作者 · 2007-9-14 09:49

我在使用flash  sst29sf040作为数据存储器时，好像得要首先声明unsigned char data型的数组，然后才能一个一个写到sst29sf040内部，也就是AT89C52要消耗掉同样多的数据空间，才能将数据写进sst29sf040,难道必须这样吗？这样不还是会消耗AT89C52的程序空间,等于没有外扩ram吗？下面是我的程序
#define _SST_C_
#include "reg51.h"
#include "sst.h"
#include <intrins.h>
#include <absacc.h>

#define FALSE             0
#define TRUE              1

#define SECTOR_SIZE          128       /*Must be 128 bytes for 29EE020*/

#define SST_ID            0xBF
#define SST_29SF040       0X13
#define uchar             unsigned char
#define uint              unsigned int
uchar data buff[5]={0x4e,0xae,0x89 ,0x39,0x43};

void  wait(uchar p,uchar q);
void  ByteProgram(uchar SrcByte,uint Dst);
int   Erase_One_Sector(uint Dst);
uchar ByteRead(uint addr);
void main()
{
    uchar i;
    Erase_One_Sector(0);

         for (i=0;i<128;i++)
    {
        if(i<5)
        {
            ByteProgram(buff,0x0000+i);
        }
         else
             ByteProgram(i,0x0000+i);
    }
    Erase_One_Sector(128);
    for (i=0;i<128;i++)
    {
        if(i<5)
        {
            ByteProgram(buff,0x0080+i);
        }
         else
             ByteProgram(0x80+i,0x0080+i);
    }

}

void  ByteProgram(uchar data SrcByte,uint Dst)
{
    XBYTE[0x0555] = 0xAA;
    XBYTE[0x02AA] = 0x55;
    XBYTE[0x0555] = 0xA0;
    XBYTE[Dst]   = SrcByte;
    //Check_Toggle_Ready(Dst);
    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  wait(uchar p,uchar q)
{
   uchar  i,j;                //(2*j+3)*i+4
for (i=p;i>0;i--)

         for (j=q;j>0;j--);
}