hello masters,

i am a software programmer in visual basic. I have not touched the hard ware programming part yet. I have devoloped an electronic circuit and trying to interface it with my software. All i need is just detect a 5volt (high signal or binary '1') on a communication port pin which would be 0 volt (low signal or binary '0') most of the time through the coding. I only know which pins is ment for which task and nothing else. Can anybody suggest me which pin to be used for the purpose and how to program ?

Any help would be greatly appreciated.