x5045.c

看门狗X5045的访问

#include <reg52.h>

extern unsigned char read_portC(void);

sbit CS    = P2^6;
sbit SI    = P2^0;
sbit SCK   = P2^1;

void  X5045_Input(unsigned char d);
unsigned char X5045_Output(void);
void  X5045_ENW(void);
void  X5045_DISW(void);

void  X5045_Input(unsigned char d)
{   unsigned char i=8;
    while(i--)
      { SCK=0;
        if(d & 0x80)
          {SI=1;SI=1;}
        else
          {SI=0;SI=0;}
        SCK=1;
        d <<=1;
      }
}

unsigned char X5045_Output(void)
{  unsigned char i=8, d;

   while(i--)
   { d <<=1;
     SCK=1;
     SCK=0;
     if((read_portC() & 0x08))
      d++;
   }
   return d;
}

void X5045_ENW(void)
{  CS=0;
   X5045_Input(0x06);
   CS=1;
}
extern unsigned char WD_RDSR(void)
{  unsigned char status;
   CS=0;
   X5045_Input(0x05);
   status=X5045_Output();
   CS=1;
   return status;
}
extern void WD_WRSR(unsigned char status)
{  X5045_ENW();
   CS=0;
   X5045_Input(0x01);
   X5045_Input(status);
   CS=1;
   while(WD_RDSR() &0x01);
}

extern void WD_RST(void)
{  CS=1;
   CS=0;
   CS=1;
}

extern void WD_WRITE(unsigned char val,unsigned char address)
{
     X5045_ENW();
     CS=0;
     X5045_Input(0x02 | ((address & 0x0100) >>5 ));
     X5045_Input(address & 0xff);
     X5045_Input(val);
     CS=1;
     while(WD_RDSR() &0x01);
}

extern unsigned int WD_READ(unsigned char address)
{
     unsigned char retval;
     CS=0;
     X5045_Input(0x03 | ((address & 0x0100) >>5 ));
     X5045_Input(address & 0xff);
     retval=X5045_Output();
     CS=1;
     return retval;
}