[Techtoolslist] Long shot but hoping
Clay Cowgill
c.cowgill at comcast.net
Wed Apr 10 15:09:22 EDT 2013
> Problem is I have 0 experience with Altera parts and I don't
> have a clue how to try getting the code out (which could very
> well be protected). I am wondering if anyone here has any
> ideas on how to pull the code out on Grid and then reprogram
> the Exotica board. My only other alternative is to remove
> the chip from the exotica board and then pull the one from
> the grid and put onto the exotica. Doable if I am lucky.
> That's a really fine pitch 100 pin part.
The USB<->JTAG programmer/interface for Altera is the "USB Blaster". It's
about $300 from Altera, but through the wonders of www.aliexpress.com you
can pick one up for about $7 (not a typo) from China... Altera has a free
download of their tool suite or just the programmer portion ("Quartus II
Stand-Alone Programmer") which should be all you need to try to read the
part. That having been said, I'd be flabbergasted if Atari didn't protect
the fusemap. (Off the top of my head I don't recall if the Altera tools
flat out *tell* you if the protection fuses are blown or if it just gives
you garbage back.)
The programmer is an easy test, so I'd probably try that first, but I
suspect you're looking at a part swap (which really isn't bad with TQFP's as
long as you have access to hot-air reflow-- or better yet, give it to
someone that's done it before to do for you).
The other thought that comes to mind is if the Altera is *just* being used
for address decode since it has lots of IO and there's no internal
state/register stuff going on, with the MAME memory map and some time
tracing all the goes-intos and goes-outtas on the chip it may be possible to
just write a new implementation of the functionality and make a works-alike
JEDEC file you could throw down on the part instead.
There's probably some places that could decap the CPLD and FIB the lock bit
fuses, but I suspect you could buy a whole pile of boards for donor parts
before you'd be at price parity.
-Clay
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