继电器

 #include <reg52.h>
 #define uint unsigned int 
 #define uchar undingned char
 sbit relay=P2^7;
 void delayn50ms(uint n)
 {
    uint i,j;
    for(i=0;i<n;i++)
       for(j=0;j<=10000;j++);
    }
    main()
    {
       while(1)
       {
      
      relay=0;
      delayn50ms(5);
      relay=1;
      delayn50ms(5);
      
    }
       
       
       
       }