Re: Mouse card --- Can EPROM go Bad?

[Rubywand <rubywand@swbell.net>]

stephen e buggie writes ...
> 
> I have two dead Mouse cards for IIe.
> 
> There is an odd Eprom with window.  Is it 2716, 2764, or 27256?  Its
> markings look strange.
>

     What are the markings? How many pins? Is it a normal 'fat' size
EPROM? By the time of the IIe, people were commonly using the 2716,
2732, 2516, and 2532.

     It seems unlikely that a mouse card would need much firmware; so,
if Apple was skimping, they may have gone with an ancient 1702 (or 1702A
... I think that's the right number).

 
> Can the mouse card IIe eprom go bad?

     If it's an EPROM, it can go bad. Mainly, it can 'forget' and need
to be re-programmed.


>   If so, can any of the standard
> 27xxx eproms be substituted for it?   I can burn a new one....
 ....

     You can substitute any of the popular oldie EPROMS with halfway
decent speed ratings if you are willing to swap a few leads and/or the
socket.



Rubywand