5 Dec
2008
5 Dec
'08
12:06 p.m.
On Thursday 04 December 2008 02:59:21 pm Chuck Guzis wrote:
On 4 Dec 2008 at 14:14, Roy J. Tellason wrote:
Because I don't know a darn thing about any of that current stuff?
This was only a couple or three logic parts, from what I can remember, not
all that much...
I've had idle thoughts from time to time
about building one of those and
sticking an EPROM between the outputs of that circuit and the device to
be driven, to convert the scan codes that you get to ASCII or whatever.
Maybe one of these days I'll get that particular round tuit. :-)
Why bother? AVRs and PICs are cheap and easy to work with (in
particular, an AVR with SPI can be programmed with little more than a
parallel port and a handful of resistors). Code for handling AT-
style keyboards abounds. One DIP--that's all that it takes. I can see the motivation to do something "the
vintage way", but even
the 5170 uses a uC to interface to the keyboard. If you wanted to go
"vintage', an 8048 or 8051-family uC would do the trick.
I remember seeing those on some old (XT-class?) MBs, for handling the
keyboard interface, but don't know much about programming those, either. I
just haven't gotten around to messing with them yet.
--
Member of the toughest, meanest, deadliest, most unrelenting -- and
ablest -- form of life in this section of space, a critter that can
be killed but can't be tamed. --Robert A. Heinlein, "The Puppet Masters"
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Information is more dangerous than cannon to a society ruled by lies. --James
M Dakin