Re: A plea: Looking for a working MM5740AAE/N for Apple II Keyboard

[rittwage <rittwage@gmail.com>]

On Dec 8, 3:07 am, Michael J. Mahon <mjma...@aol.com> wrote:
> rittwage <rittw...@gmail.com> wrote:
> > On Dec 7, 2:49 am, "Michael J. Mahon" <mjma...@aol.com> wrote:
> >> rittwage wrote:
> >>> I have an old Apple II that I've fixed every other odd problem
> >>> (besides a broken Applesoft E0 ROM) except the keyboard!
>
> >>> I found some AAC/N chips, but no luck- the encoding is wrong.  I need
> >>> to see if any kind soul has any AAE/N encoder chips left to spare.
>
> >>> I really hate to convert to PS/2- I like the original keyboard.
> >>> Without that, I might as well use an emulator.  :)
>
> >> Pete, I'd recommend keeping this thread in csa2 and avoiding
> >> crossposting to marketplace and emulators.
>
> >> Are you sure that the problem is the encoder chip, and not
> >> one or more shorted keyswitches?  Failed encoders are not
> >> the most common keyboard problems.
>
> >> If it is the encoder, then you will have a hard time finding
> >> an equivalent replacement.  It would be possible to construct
> >> an equivalent that plugs into the original electrical "footprint",
> >> but it's not a simple project.
>
> >> Since the encoder presents parallel ASCII to the Apple II, it
> >> should not be too difficult to replace the keyboard with, say,
> >> a later Apple ][+ keyboard.  Those used to be pretty plentiful,
> >> depending on how authentically "Apple" it had to be...
>
> >> -michael
>
> > It's definitely the encoder- the original does nothing and the AAC
> > works, but has all wrong keys.  No switches are shorted, and I traced
> > to find no "stuck" bits.  It's just that the AAC, AAD, etc. send
> > different keystrokes to the AAE.
>
> > This is an early Datanetics keyboard without the separate encoder
> > board, so that modern encoder board replacement won't work.  Also, I
> > know I can replace the keyboard entirely with a PIC and a PS/2
> > keyboard, but... yuck.  I know I can also swap the whole keyboard for
> > another, but they are about as hard to find!
>
> > I do have extra IIe keyboards, but to my knowledge they can't be
> > converted.  Or can they?
>
> > -Pete
>
> Yes, it shouldn't be hard to adapt a //e keyboard to an Apple II.  You'll
> need to stay in caps lock to keep things simple.
>
> -michael - NadaNet 3.1 and AppleCrate II:http://home.comcast.net/~mjmahon

Maybe, but the keyboard footprint is different- you can't mount one in
a IIe case.
I guess I'll wait until I can find a chip or another II keyboard one
day...  :(

-Pete