step13.c

不少单片机C代码

#include <reg51.h>
#define DL 500
#define DR 1
#define uchar unsigned char
#define uint  unsigned int

void  dlms(uint x);

void ctrl(cf,n)
 bit cf;
 uint n;
{ uint i;
  uchar j=0x01;
  if(cf=0)  for(i=0;i<n;i++)
	     { P1=j;
	       dlms(DL);
	       j=j<<1;
	       if((j^0x08)==0)  j=0x01;
	     }
   else
     { for(i=0;i<n;i++)
	{ P1=j;
	  dlms(DL);
	  j=j>>1;
	  if(j==0) j=0x04;
	}
     }
 }

void main(void) 
{
  if (DR==1) ctrl(1,100);
  else  ctrl(0,100);
}