Hi All

Thanks god , now I can blink my LED's
The problem before is on C syantax.

I ( with help of friend ) change the code as below

#include <at89c55wd.h>
#include <stdio.h>

int counter;
int counter1;

void wait(void);


void main(void)
{
start:
T2 = 0;
wait();
T2 = 1;
wait();
goto start;
}

void wait(void)
{
int a,b,z;
for (a=0; a<2000; a++)
{
for (b=0; b<20; b++) {z=5;}
}
}


p/s:
what I mean with:
1. minimun microcontroller is actually minimum microcontroller circuit ie just with Vcc, Crystal and Reset switch.
2.Pull up LED is just like Steave said :one end of the resistor to +5, one end to LED anode, LED cathode to port pin
3.about pin state toggle but LED not blink, I don't know why .. may be there's ghost inside .... :)


Regards
Parif