[alt.msdos.programmer] How to watch the parallel port?

haverlan@boulder.Colorado.EDU (HAVERLAND MARC BRADLEY) (06/03/90)

I have a problem that I'm not too familiar with that I would like
to get comments on.  Any help is much appreciated.

The problem:  I need to watch the parallel port for an ASCII 7 (bell)
and send a bell to the serial port whenever I find one.  I also need
to let everything continue to go to the parallel port.  It would be
acceptable to simply copy everything going to the parallel port to the
serial port.

I don't think I can use MODE redirection, because I still need to let
the data out the parallel port.  What I need to do is *copy* the data.

Can I watch the parallel port with a simple TSR? Where would I look?
Where would I send it once I found it?  I'm not too familiar with TSR
programming, but it seems this would be a very small program that could be
written fairly easily.

For those interested, the specific problem is this:  a client with an
old Novell network and point-of-sale software that sends an ASCII 07 to
the parallel port to open a cash drawer, and a cash drawer that goes on
the serial port that accepts an ASCII 07 to open the drawer.  They still
need to have a printer on the parallel port.

Thanks to anyone with a suggestion.

Marc Haverland         haverlan@tramp.colorado.edu         (303) 650-1100