//#include <reg52.h>
//#include <stdio.h>
//xjj chang 。
sbit SO=P1^2;
sbit SI=P1^3;
sbit SCK=P1^5;
sbit CS=P1^6;

//25045可編程看門狗監控EEPROM指令集
#define WREN 0x06; 00000110 //設置寫使能鎖存器（允許寫操作)
#define WRDI 0x04; 00000100 //復位寫使能鎖存器（禁止寫操作）
#define RDSR 0x05; 00000101 //讀狀態寄存器
#define WRSR 0x01; 00000001 //寫狀態寄存器（塊鎖定）
#define READ 0x03; 00000011 //從開始于所選地址的存儲器列陣中讀出數據
#define WRTE 0x02; 00000010 //把數據寫入開始于所選地址的存儲器陣列中（1至4字
節）

void in_byte(unsigned char BYT);
unsigned char out_byte(void);
unsigned char rdsr_dog(void);
void wrsr_dog(unsigned char status_reg);
unsigned char wip_poll(void);
void wrdi_dog(void);
void rest_dog(void);
unsigned char byte_read(unsigned char H,unsigned char L);
void byte_write(unsigned char H,unsigned char L,unsigned char D);
//void page_read(unsigned char H,unsigned char L,unsigned char D);
//void page_write(unsigned char H,unsigned char L,unsigned char D);

unsigned char rda[8];
unsigned char cs_rda[8]; 
//看門狗寫使能子程序
void wren_dog(void)
{
// unsigned char com;
// com=0x06;//WREN;
SCK=0;
CS=0;
in_byte(0x06);
SCK=0;
CS=1;
}

//看門狗寫禁止子程序
void wrdi_dog(void)
{
//unsigned char com;
//com=0x04;//WRDI;
SCK=0;
CS=0;
in_byte(0x04);
SCK=0;
CS=1;

}



//寫狀態寄存器
void wrsr_dog(unsigned char status_reg)
{
// unsigned char com=0x01;//WRSR;
SCK=0;
CS=0;
in_byte(0x01);
in_byte(status_reg);
SCK=0;
CS=1;
wip_poll();
}


//讀狀態寄存器
unsigned char rdsr_dog(void)
{
// unsigned char com=0x05;//RDSR;
SCK=0;
CS=0;
in_byte(0x05);
return(out_byte());
SCK=0;
CS=1;
}

//字節讀
unsigned char byte_read(unsigned char H,unsigned char L)
{
unsigned char data_dog,add;
SCK=0;
CS=0;
SO=1;
SI=1;
add=H<<3;
add|=0x03;//READ;
in_byte(add);
add=L;
in_byte(add);
data_dog=out_byte();
SCK=0;
CS=1;
return(data_dog);
}
//字節寫
//H,地址高字節；L地址低字節；D寫入的數據
void byte_write(unsigned char H,unsigned char L,unsigned char D)
{
unsigned char data_dog,add;
SCK=0;
CS=0;
SO=1;
SI=1;
add=H<<3;
add|=0x02;//WRTE;
in_byte(add);
add=L;
in_byte(add);
data_dog=D;
in_byte(data_dog);
CS=1;
wip_poll();
}
//復位看門狗子程序
void rest_dog(void)
{
CS=0;
CS=1;
}


//檢驗寫操作是否結束。
unsigned char wip_poll(void)
{
unsigned char i;
unsigned char wip;
for(i=0xff;i>=1;i--) 
{
wip=rdsr_dog();
wip&=0x01;
if(wip==0) break;
}
return(wip);

}

//單字節指令或數據寫入X25045
//在SI線上輸入的數據在SCK的上升沿被鎖存。
void in_byte(unsigned char byt)
{
unsigned char i;
//SCK=0;
//CS=0;
for(i=8;i>=1;i--)
{
SCK=0; 
SI=byt&0x80; 
SCK=1; 
byt=byt<<1; 
}
// SI=0;
// SCK=0;
// CS=1;
}

//單字節數據從X25045讀到單片機
//數據由SCK的下降沿輸出到SO線上。
unsigned char out_byte(void)
{
unsigned char i;
unsigned char byt;
//SO=1;
//SCK=0;
//CS=0;
for(i=8;i>=1;i--)
{
byt=byt<<1;
SCK=1;
SCK=0; 
byt|=SO; 

}
//SCK=0;
//CS=1;
return (byt);
}