//函数声明
#include ”reg51.h”
#include ”intrins.h”
//管脚声明
sbit CS?_93=P1^0
sbit CLK?_93=P1^1
sbit DI?_93=P1^2
sbitDO_93=P1^3
sbit VCC?_93=P1^4
#define READ_c 0x02
#define WRITE_c 0x01
#define RRASE_c 0x03
#define RWEN_c 0x00
#define RWDS_c 0x00
#define RRAL_c 0x00
#defineWRAL_c 0x00

void delay(unsigned int N)
{
 int i;
 for(i=0;i<N;i++)
}

void SEND_1(void)
{
 DI_93=1;
 CLK_93=1;
 _nop_();
 CLK_93=0;
_nop_();
}

void SEND_0(void)
{
 DI_93=0;
 CLK_93=1;
 _nop_();
 CLK_93=0;
_nop_();
}

void start_operation(unsigned char operation_code)
{
 CS_93=1;
 SEND_1();
 if (operation_code&0x02)
 SEND_1();
 else
SEND_0();
if (operation_code&0x01)
SEND_1();
else
SEND_0();
}

void SEND_BYTE(unsigned char dd)
{
 unsigned char i;
 for (i=0;i<8;i++)
    {
     if (dd>=0x80)
     SEND_1();
     else
     SEND_0();
     dd=dd<<1
     }
}

unsigned char RECEIVE_BYTE(void)
{
 unsigned char i,dd;
 DO_93=1;
 for (i=0;i<8;i++)
   {
     dd<<1;
     CLK_93=1;
     _nop_();
     CLK_93=0;
     _nop_();
     if (DO_93)
     dd!=1;
    }
 return(dd)
}

void EWEN(void)
{
 _nop_();
 CS_93=1;
 start_operation(EWEN_c);
 SEND_BYTE(0xC0);
 CS_93=0;
}

void EWDS(void)
{
 _nop_();
 CS_93=1;
 start_operation(EWDS_c);
 SEND_BYTE(0x00);
 CS_93=0;
}

void ERAL(void)
{
 _nop_();
 CS_93=1;
 start_operation(ERAL_c);
 SEND_BYTE(0x80);
 CS_93=0;
}

unsigned char READ_BYTE(unsigned char address)
{
 unsigned char dat;
 CS_93=CLK_93=0;
 CS_93=1;
 start_operation(READ_c)
 SEND_BYTE(address)
 dat=RECEIVE_BYTE();
 CS_93=0;
}

bit WRITE_BYTE(unsigned char address,unsigned char dat)
{
 unsigned char e,time,temp=address;
 e=0;
 while(e<3)
   {
     CS_93=CLK_93=0;
     CS_93=1;
     EWEN();
     _nop_();
     CS_93=1;
     _nop_();
     start_operation(WRITE_c)
     SEND_BYTE(address);
     SEND_BYTE(dat);
     CS_93=0;
     _nop_();
CS_93=1;
     time=0;
     DI_93=1;
     while(1)
       {
        if (DO_93==1)
        break;
        if (time>20)
        break;
        time++;
       }
     CS_93=0;
     if (READ_BYTE(temp)==dat)
       {
         return(0)
        }
      e++
        }
         return(1);
   }