>I wasn't clear in the explanation of my problem!
>
        I wanna to do a HARDKEY for my Software (using the parallel port), >but
i don't
> want
>to have problems with this same port for print something!


>
>        Parallel <--------->Cable printer
                   Hardkey

>        Miguel.

The standard way of doing this is to interface to your hard key without ever
activating the strobe line of the parallel port.  Most all printers will ignore
data line activity until the strobe line is active.  Send out your data on D0 to
D7, have your hard key interpret the data and answer on the status lines (
status lines are input only), while always leaving the strobe line inactive.

------- Steve