Re: Mousecard HW question...

[Randall Frank <randall-frank@computer.org>]

Wayne,
	Thanks for the info.  I think I can track down a
burner and will try making a new EROM. One thing, if an
EPROM goes bad, will its output look like static or 
dynamic garbage?  Right now, every time I list the ROM
for the slot (C400L), I get different information (very 
much not 6502 code).  My concern is that there may be 
more wrong with this card than just the EPROM.

Thanks.

Wayne Stewart wrote:
> 
> Randall Frank wote
> > Hello,
> >       I just picked up a mouse card (670-0030-C, 1983) and
> > poped it into my //e, slot 4.  Everything that looks for the
> > mouse came back saying there was no mouse.  So, I quick listed
> > the ROM at $C400 and found that there was no ROM there (random
> > bytes that changed with each read).  So, I think I may have a
> > defective card (yes, it does have all the chips on it).  I notice
> > that there are two pads on the card labeled 'X1' and 'X2' any
> > chance I need to open one up (X1 is closed) or solder one
> > closed (X2 is open)?  I have tried other slots and get the sam
> > results, no ROM.
> >       Any other diagnostics someone might suggest?  It looks
> > like a pretty simple card...
> >
> > Thanks.
> 
> X1 and X2 have to do with which chip is in the socket directly above
> them. If you have the chip labeled 341-0285 then X1 is closed and X2
> open. If chip has a sticker on it labeled 341-0269 or a clear window
> then X1 is open and X2 closed.
> 
> It's possible the EPROM is suffering from bit rot. EPROMs do lose
> their programming over time. If you have access to an EPROM burner
> or get a shop to burn one you can download the image from my website.
> It's a 2716 EPROM
> http://homepage.mac.com/waynes
> 
>         Wayne

-- 
rjf.
Randy Frank                            | ASCI Visualization
Lawrence Livermore National Laboratory | rjfrank@llnl.gov
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