Hey Saathis, it seems you are very new to vb6 , am i right , in one blog you asked about parallel port programming also ,anyway,
seems you are having
1. Ur pc parallel port
2. Parallel port is connected to a analogous variac
and 3. the controlled variac output is to your motor directly .
Am I right Saathish. If it is then you should know what are the bit patterns available for step voltage increase and step voltage decrease for your stepper motor.
Then it's simple to implement in vb6, add "inpout32.dll" in your application and simply use
PortState% = vbInp(PortAddress%)
PortNum% = PortState% + OutNum%
vbOut PortAddress%, PortNum%
for your application.
The details for adding the dll and using that is already explained in your parallel port programming message.
Wish you best of luck and i know you will be able to do it by your own...
Regards,
Saubhik