The LPT1 has always been present in BIOS from the beginning PC. Hardware implementation varied. The physical address of the port on the monochrome adapter was different from the other implementations. BIOS assigned the neccessary linkage on boot to sort out LPT1 & LPT2. The original bidirectional capabilities were limited to what the Epson MX80 printer needed for handshake. Trying to determine what was "first" is impossible since there were so many innovations that seemed to happen concurrently around the world. I still have many examples of the old hardware in my shop taking up room. Last year I took a monochrome monitor and adapter to the dump, complete with origonal packing. No takers around here, too expensive to ship! I will soon relocate the collection to the garage attic (hot!) or take it to the dump. History is a lot less interesting if you were there.... John Ferrell 6241 Phillippi Rd Julian NC 27283 Phone: (336)685-9606 Dixie Competition Products NSRCA 479 AMA 4190 W8CCW "My Competition is Not My Enemy" ----- Original Message ----- From: "Michael Pont" To: Sent: Monday, March 24, 2003 4:57 AM Subject: [OT] History of the PC parallel port > Hi, > > I'm trying to do a little bit of background reading for an article I'm > putting together. > > Specifically, I'd like to find out which version of the IBM PC family first > included a parallel port. As far as I can tell, this was the IBM 5170 > PC/AT, released in 1984. > > Anyone know if this is correct (or suggest a reliable source of such > information)? > > Thanks, > > Michael. > > +==================================+ > > Michael J. Pont, PhD > Embedded Systems Laboratory > University of Leicester > > http://www.le.ac.uk/eg/embedded > > +==================================+ > > -- > http://www.piclist.com hint: The list server can filter out subtopics > (like ads or off topics) for you. See http://www.piclist.com/#topics > -- http://www.piclist.com hint: The list server can filter out subtopics (like ads or off topics) for you. See http://www.piclist.com/#topics