Finally i got my hands on SDCC
Now after learning this sufficiently i will try keil also
first one should try simple programs. So one can asure all things are allright.



/* Author Nikhil S Arora
ele.nikhil@gmail.com
program 1
Checking if condition
if port3.1 is high make p1=00 and if port3.1 is low then make p1=ff
and this goes on continuosly
*/
#include <at89x051.h>
void main(void)
{
while(1)
{
if(P3_1)
P1 =0x00;
else
P1 =0xff;
}

}

second program

#include <at89x051.h>
void main(void)
{
int i;
char j;

while(1)
{
P3 =0xff;
for(i=0;i<1000;i++)
{
for(j=0;j<100;j++)
{}
}
P3 =0x00;
for(i=0;i<1000;i++)
{
for(j=0;j<100;j++)
{}
}
}

}