From: shad04@ccu.umanitoba.ca (Dan Fandrich)
Subject: Re: IBM keyboard to CBM
Organization: University of Manitoba, Winnipeg, Manitoba, Canada
Date: Sun, 22 Nov 1992 22:40:22 GMT

In article <92324.081236EAO102@psuvm.psu.edu> Ernie Oporto <EAO102@psuvm.psu.edu> writes:
>I have heard of a project where you can take an IBM 101-key keyboard
>and connect it to a C128.  If anyone has any documentation on this
>project, please let me know.  I'm really interested in doing this to
>my machine.

Here's a message I saved from last year.  I haven't actually tried the i/f
myself, so I can't supply any more info.  Also, fingering the jomby address
yields no such user.  Hopefully the author changed his mind and allowed the
plans to be made available via ftp somewhere.


From: kolstad@jomby.cs.wisc.edu (Joel Kolstad)
Newsgroups: comp.sys.cbm
Subject: Wanna use a PC Keyboard with your C-64?
Date: 16 Apr 91 03:50:08 GMT
Organization: U of Wisconsin CS Dept
Originator: kolstad@jomby.cs.wisc.edu

From: kolstad@jomby.cs.wisc.edu (Joel Kolstad)
Newsgroups: comp.sys.cbm
Subject: Wanna use a PC keyboard with your C-64?
Followup-To: 
Distribution: world
Organization: U of Wisconsin CS Dept
Keywords: 

Well, after becoming very frustrated with my always dirty, rarely working
very well original Commodore 64 keyboard, I decided to built myself an
IBM PC to Commodore 64 keyboard interface.

I finished this little hack this past weekend, and am now happily typing
on a Bondwell PC-XT keyboard going through my circuit to a C-64 (this
was about the cheapest PC keyboard I could find... $25 from Lesko's, in
Wisconsin...).

The circuit is quite simple... just two chips: An Intel 8748 microcontroller
(yes, ancient, I know) and a (New! :-) ) Dallas Semiconductor's 8x8 Cross
Point switch.  (What's rather ironic, here, is that many PC keyboards,
including this one from Bondwell, use 8x48s themselves! :-) )

The 8748 just watches the PC keyboard's scan codes, and figures out what to tell
the 8x8 Cross Point switch to do -- that is, what keys to "fake" on the
Commodore 64 keyboard.

I think I did a decent job on the tiny program that runs the 8748... Caps lock
is supported, Num lock is supported, shifted PC keys function like their 64
counterparts should, hitting arrow keys on the PC keyboard automatically
adds shifts when needed, etc.  Overall, pretty much transparent to the user.
The only place wher there are a few quirks is in "non-standard" characters
such as vertical bars, tildes, etc.  I tried to map this characters into
the most standard C-64 keys I could, but by their natur of being non-
standard keys, how perfect the translation is depends on what the program
is looking for. :-) Also, sending "impossible" key combinations (like,
hitting Shift-2 (@) and U and the same time on the PC keyboard) won't
produce useful results.  But I wouldn't expect it too...

Personally, my C-64 and its assorted hardware lives in a big metal box, so it
was no problem to stick in another board.  But for people who would want to 
keep their original cases, it'd probably be possible to just drill a hole
for the keyboard connnector in the case, anad keep the circuit board inside.
Since this thing uses a crosspoint switch, a simple passthru lets both the
C-64 and PC keyboard work at once -- now there's where we could see
some productivity!  But more importantly, this means you can still use the
C-64 keyboard when there isn't a PC keyboard plugged in.

Sound useful?  Good!  Since I doubt I could ever generate enough interest
in this to make any money, I'm releasing it as more or less "public domain
hardware."  If anybody wants a schematic or more information, you can
mail me at my below e-mail address.  Sorry to say that I can only provide
HPGL or Epson printer dump outputs.  If you want the code for the 8748,
you can have Intel Hex format, or UUencoded binary.

I'd appreciate it if anyone sending for schematics and/or 8748 listings
keep the things off of FTP sites, and such, for awhile -- I might just
try to sell this to some magazine. :-)  All of you who want more
information, then, are my close personal friends and beta testers. :-)

That's about it.  I hope someone out there finds this as useful as I have --
I _love_ my new keyboard!

---Joel Kolstad
kolstad@jomby.cs.wisc.edu


>>> Dan
-- 
Internet: shad04@ccu.umanitoba.ca               Compu$erve: 72365,306