GAL help

Cmndr Brain

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Through a series of unfortunate events, that included burning my finger, 5 Lattice GAL chips on a circuit board I was working on got cooked. How can these chips be replaced? Where can I get the file to burn new ones if that's possible? Or, does someone do it for a fee? I have pretty good experience w/ ram/rom chips, but GAL/PLD's are completely new to me. They are "Lattice GAL16V8A-25LP".
 
Most GAL chips are read protected so unfortunately your probably SOL.

There are a few sprinkles of GAL dumps around, if you list the game someone

might be able to help.
 
Nobody has the JEDEC for this one? Only takes a few seconds to read one to see if it is write protected or not. 16V8's are a dime a dozen.

Ed
 
doesn't look like there in mame , so there probably just used for address mapping.

there is an off the wall pcb on ebay right now, not sure if that is an option for you.


http://www.ebay.com/itm/OFF-THE-WAL...640?pt=LH_DefaultDomain_0&hash=item257a6c9a18

Thanks, I actually have a spare pcb. I was able to swap the 5 gal chips to the bad board and got it to work. I've worked on board repair before and have no problems with eproms and the like. But, gal's and pld chips I've never had the pleasure of working with until now. I understand the concept but didn't think you could just read them like an eprom and burn a new one. I've been considering a new chip burner to supplement my current one. How could I go about burning new ones?
 
How could I go about burning new ones?

I think many of the newer burners should do GAL chips.

But to create the JDEC file that defines the fuses that get 'blown' in the gate array, you would have to have an idea of what they are doing.

In alot of games, they simply act as address decoders or the like - 1 GAL chip can replace a bunch of 74xx gates, and the fuses define how the gates in the array connect to each other.

IIRC maybe Lattice semiconductor has a freebie GAL development environment that will allow you to create the fuse configs for various flavors of GAL. Search around - they are pretty usefull, but hard to wrap your head around....
 
if you have working gals, you maybe able to do a little circuit testing with a la or probe, and build a device that would pass input values and record output values, if the chip is just being used as a simple address decoder, then it should be relatively easy to build a jedec file, check out wincupl (amtel ) , the output jedec should go fine to a lattice gal, most gal's can be re-written over ( as least the lattice gal16v8d i have)

the only time reverse engineering will be hard is if the incorporated latch/adders/sub-tractors into the logic.. ie, access a 0x08 input gives you say, 0x03 out, then you goto 0x09 and it gives you 0x04, but then if you go back to 0x08 it gives another value then what you had before, random noise input will repeatable output indicates that there shouldn't being any crazy logic.

also, if the schematic is available, it will make it easier to figure out the inputs and outputs, and then with the mame source, sort out address selects based on the input pins.

not all programmers will write them, i picked up a top853 for $50 on the bay that works fine burning gal's

is there any numbers stamped on the gal? maybe doing a google search may find a dump of one.
 
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