Date   : Fri, 19 Mar 1999 13:56:13 -0000
From   : "Fraser, Colin J" <Colin.Fraser@...>
Subject: Re: the ultimate in bbc emulation

> -----Original Message-----
> From: Mark Usher [mailto:marku@...]
> Sent: 19 March 1999 13:28
> To: BBC MICRO Mailing List POSTINGS (E-mail)
> Subject: [BBC-Micro] the ultimate in bbc emulation
> 
> A while ago JGH was talking about attaching a PC keyboard to 
> a BBC, and how
> it could be achieved. Now, in one of my rare moments, it 
> occurred to me that
> it would be the ultimate to attach a BBC keyboard to a PC, 
> just to get the
> correct feel of an emulator.
> 
> Any thoughts apart from those on the state of my mental health :-)

You can pick up a PC keyboard for next to nothing these days. You could
extract the controller chip from a cheapo PC keyboard, and connect it up to
the switch matrix of a BBC keyboard. I doubt the matrix layout would map
correctly to what the PC controller was expecting, so your emulator would
need to use a custom key map. If your PC can cope with the keyboard being
removed and reconnected without rebooting, then you could add a switch box
to switch from the normal keyboard to the BBC keyboard when you start up
your emulator.
If you wanted to remap the BBC keyboard matrix to use as a standard PC
keyboard (missing a few keys of course), you could code your own keyboard
scanning software for a microcontroller, and give it a PS2 serial output.
The complement to this would be to build a PS2 keyboard to BBC interface
that would allow you to use the PS2'd BBC keyboard with a real BBC.
Whether this is worthwhile probably depends on how many people have BBC
keyboards from unrepairable Beebs.


Colin f