LED X patern

Refer 'LED Basic Circuit' in 'Embedded Systems Circuits' Label


#include<reg51.h>
#include<intrins.h>
void ms_delay(unsigned int a)
{
unsigned char b=255;
for(;a-->0;)
for(;b-->0;)
_nop_();
}


void main()
{
 unsigned char i,a,b,c;
 while(1)
 {
  a=0xfe;
  b=0x7f;
  for(i=0;i<8;i++)
  {
   c=a^b;
   c=~c;
   P1=c;
   a=a<<1;
   b=b>>1;
   ms_delay(500);
  }  
 }

}