2.26

#include<reg52.h>


void timer0_init()
{
    EA = 1;
TMOD |= 0x01;
TH0 = (65536 - 50000)/256;
TL0 = (65536 - 50000)%256;
ET0 = 1;
TR0 = 1;
}


void timer0_isr() interrupt 1
{
    static unsigned int i = 0;


TH0 = (65536 - 50000)/256;
TL0 = (65536 - 50000)%256;
i++;
if(i == 20)
{
   i = 0;
Led = ~Led;
}
}


void main()
{
    
}