If you can scrounge the key switches and caps you need from an extra
PC-keyboard, that's great! As for the displays, I'd suggest you either (1) wire
the displays in parallel with what's already there, or (2) fabricate a duplicate
driver circuit, with both the encoders (or segment drivers) and the digit
selects (I haven't yet looked at the schematic to see what's easiest) as well as
the current-limiting resistors. The latter will provide more satisfying
results, methinks. I'd recommend LARGE displays and a convenient keypad layout.
The reason will become obvious as you get older.
Dick
----- Original Message -----
From: "Ross Archer" <dogbert_at_mindless.com>
To: <classiccmp_at_classiccmp.org>
Sent: Friday, April 13, 2001 7:17 AM
Subject: Re: Kim / Commie keypads
>
> ----- Original Message -----
> From: Richard Erlacher <edick_at_idcomm.com>
> To: <classiccmp_at_classiccmp.org>
> Sent: Wednesday, April 11, 2001 11:41 AM
> Subject: Re: Kim / Commie keypads
>
>
> > Yes ... cannibalizing a PC keyboard might be a solution, provided you can
> come
> > up with a way to modify the keycap legends.
>
> Or not.
>
> 0-9 ==> 0-9 (from top row)
> A-F ==> A-F
> AD ==> * (from numeric keypad)
> DA ==> Insert (from stand-alone pad)
> PC ==> P
> + ==> +/= (or + on numeric if not oversize cap)
> GO ==> G
> ST ==> S
> RS ==> R
>
> Of course, you could duplicate the layout exactly.
>
> :)
>
> Thanks for the ideas again. This ought to work relatively
> well.
>
> The outboard display is mostly no-go though.
> Although the 7-segment digital lines go out to
> the application connector, where they can be
> re-buffered with a 74HC06 or similar, the lines
> to select which LED to light at any particular scan
> moment (nor the raw undecoded input selecting them)
> do not leave the board. I'd have to solder to something,
> whether it was the 6530 or the decoder. For obvious
> reasons, if I did solder to it, it would be on the decoder
> outputs x 6, since I can get another one of those if they fried. :)
>
>
> > MicroSwitch once made keyboard
> > switches that had an undersized keycap with a clear plastic cover that was
> > "normal" sized. You could put a paper legend underneath the clear cover,
> > obviously, and thereby avoid having to replace it all the time, not that
> > replacing it would be a big chore.
> >
> > Dick
> >
> > ----- Original Message -----
> > From: "Sellam Ismail" <foo_at_siconic.com>
> > To: <classiccmp_at_classiccmp.org>
> > Sent: Wednesday, April 11, 2001 1:12 AM
> > Subject: Re: Kim / Commie keypads
> >
> >
> > > On Wed, 11 Apr 2001, Ross Archer wrote:
> > >
> > > > But still I would like a "nice looking"
> > > > keypad, or at least "not amateurish".
> > > > So does anyone know where one might find
> > > > a "take a bunch of keycaps and fit into a plastic
> > > > grid to make your own keypad array" sort of kit?
> > >
> > > Maybe you can find an old calculator with a suitable keypad and
> > > cannibalize it? Or perhaps some old PC numeric keypad?
> > >
> > > Sellam Ismail Vintage Computer
> Festival
> >
> > --------------------------------------------------------------------------
> ----
> > > International Man of Intrigue and Danger
> http://www.vintage.org
> > >
> > >
> >
>
>
Received on Fri Apr 13 2001 - 10:18:46 BST