#include <REG2051.H>
sbit led=P1^0;
sbit k1=P1^6;
sbit k2=P1^7;
void delay(unsigned char ms)
{
    unsigned char x,y;
    for(x=0;x<ms;x++)
    for(y=0;y<50;y++);
}

void main()
{
  unsigned char i,a=10,b=1;
  k1=1;
  k2=1;
  led=1;    
    while(1)
    {
        led=0;
        delay(a);
        led=1;
        delay(b);
        if(k1==0)
            delay(5);
            if(k1==0)
            {
                while(!k1);
                a++;
                b--;
            }

            if(k2==0)
                delay(5);
            if(k2==0)
            {
                while(!k2);
                a--;
                b++;
            }
            if(a>9)
            a=10;
            if(b<2)
            b=1;                
    }
}