Re: IIe Keyboard

[Rubywand <rubywand@swbell.net>]

Bruce R. Baker writes ...
> 
> My experience is that this is more simple than it looks.  You have one
> stuck key.  It is stuck down.  Have you opened the machine and moved the
> keyboard?  If so you may have replaced it wrong, it is rubbing on one of
> edges.  The key that is stuck is next to the edge.
> 
> If this does not apply to you, often pressing all the keys until it stops
> (because by pressing on the right key, it comes unstuck) will work.
> 

     For sure, checking for a stuck key is a good idea!

     In this particular case, the symptoms do not seem to fit a stuck key:

> > ....
> > Every time you push a key it keeps on repeating until you push another
> > that continues to repeat. ....

     Normally, a stuck letter, number, etc. key would be filling the 
screen with A's, 9's, or whatever. Depending upon whether or not a keyboard 
locks out other keys, a second key, say a V, would either not be recognized 
or would be displayed along with the stuck key (like 999999999 <press V> 
9V9V9V9V9V9V9V <release V> 9999999999 ...).

     Unless this particular IIe has a keyboard with the old REPEAT key and 
this key is stuck (OR, the problem occurs only when running a particular 
program) there would seem to be no stuck key which produces the symptoms 
Keegan describes.

     The rationale for going to the bother of re-socketing the KB Controller 
and IOU IC's has to do with the 'Key Down',etc. signals going from the KR 
3600 KB Controller to the IOU. Both signals appear to be active High. 
Normally, High is also the state of an unconnected input.

     Were there a break in, say, the Key Down line, the IOU would believe 
that the most recently pressed key is always being pressed. With luck, the 
problem is just a bad socket-to-pin contact and re-socketing will scrape off 
some gunk and reestablish a good contact.

     Even so, maybe I've missed something. Actions like pulling any joysticks 
and diddling the keys take little effort and are worth a try. 



Rubywand