Re: JEDEC File decoding

Kev wrote:
>
> I know this is a bit off topic but this is best way to reach the
> brightest minds of the collecting/gaming community.....
>
> I have a JED file on disk, can this be converted to a logic gate
> equivalent?
>
> The reason that I ask, this chip is used on a auxilary board plugged
> into a Pac-Man pcb to run a few different games and if I can dechiper
> what it is doing, possibly these games may be emultated and run on a Pac
> board as EPROMs only.
>

Should you choose to go the route of figuring out what the chip does,
rather than trying to reverse engineer the JEDEC file, you'll find a
logic analyzer an invaluable tool. The analyzer won't actually decode
the logic for you, but it will let you perform state analysis on several
dozen I/O pins simultaneously. It's basically like having a storage
scope with lots of I/O that works on logic level signals only. Once you
have the state information, then you'll be able to start the real
decoding of what all the data means. Don't be fooled though. This is a
terribly challenging task. Cliff Kotch went through similar procedures
when he figured out how the ESB slapstick worked. Once he figured out
the algorithm, he wrote his own program for accomplishing the same
thing. So, it's not impossible, but it certainly isn't easy. (See,
this was somehow vector related!)

Good luck!

Joel-
Received on Tue May 26 07:29:19 1998