4-3.c

这是用proteus和keil两个平台一起完成的

#include<reg51.h>
#define unchar unsigned char
#define unint  unsigned int

unchar code ch1[]={0x01,0x02,0x04,0x08,0x10,0x20,0x40,0x80};
unchar code ch2[]={0x03,0x06,0x0C,0x18,0x30,0x60,0xC0,0x00};

void delay(void)
{
 unint i,j;
 for(i=0;i<200;i++)
  for(j=0;j<153;j++)
  ;
}

void main()
{
 int i;
 while(1)
  {
   switch(P1)
    {
	 case 0x03 :
	 for(i=0;i<8;i++)  {P2=ch1[i];delay();}  break;
	 case 0x02 :
	 for(i=7;i>=0;i--) {P2=ch1[i];delay();}	 break;
	 case 0x01 :
	 for(i=0;i<8;i++)  {P2=ch2[i];delay();}	 break;
	 case 0x00 :
	 for(i=7;i>=0;i--) {P2=ch2[i];delay();}	 break;
	 default: break;	
	}
  }
}