5 Dec
2008
5 Dec
'08
1:57 p.m.
On 4 Dec 2008 at 21:17, Tony Duell wrote:
I thought the idea was to use any PS/2 keyboard, in which case having to
modify that ws a bad idsea.
But yes, you could remove the intenral electronics from the keyboard and
be left with a matrix of switches. Encoding that to ASCII is a very
standard problem which has been solved many times (and using TTL).
Whgy does it have to fit in the keyboard enclosure? The PS/2 -> 8 bit
parallel interface is an external unit, surely? In which case the
switc_matrix->8 bit interface can be too, linked with a bit of ribbon
cable to the keyboard matrix.
-tony
This makes no sense commerically, I agree. If I
was going to make this as
a product, or part of one, I'd use a microcontroller. Period. But classic
computign is a _hobby_ for me, and darn it, I get to do it the way I
enjoy. And if that means a board of TTL chips. that's my business.
Perhaps a good place to start would be to replace that pesky uC in
the keyboard itself with a bunch of TTL--if you could still get the
result inside the enclosure.