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Cruisin USA A-19993.U38 dump (Linking chip)

TheDrunkenArcade said:
what do you mean by "if its not registered" so I finally found someone to sell me one.. I have it coming monday. what do I need to do to read the chip? Im going to throw it in my eeprom reader (TL866cs) and try to dump it/copy it so I have the 2 that I need to link these machines - or is this not going to be as straight forward as I think?
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skate323k137 said:
TheDrunkenArcade said:
what do you mean by "if its not registered" so I finally found someone to sell me one.. I have it coming monday. what do I need to do to read the chip? Im going to throw it in my eeprom reader (TL866cs) and try to dump it/copy it so I have the 2 that I need to link these machines - or is this not going to be as straight forward as I think?
Click to expand...
It's not a straight forward dump. It's essentially a brute force process of pulling pins high and low to determine the behaviour of the chip to reproduce the jed. I don't know how to do it but that's my understanding.
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skate got it, the chip is probably protected which mean you can't read it on your programmer even if it supports it.
No registered means there's isn't any latches involved in the logic between the inputs and outputs of the chip so the chip can be seen as a big table: for each combination of inputs you have one combination of outputs.
To brute" read" the chip you need to build an adapter that makes it seen as an EPROM for your programmer. Reading it will generate a big file (inputs will be simulated by address lines, outputs will be read from data lines). Finally equations between inputs and outputs will have to be deducted with a tool and reduced in order to fit in a PAL/GAL.
 
Gotcha.. ya I have been continuing my research into it. I found the schematics for the adapter from a German Guy that does old apple pal chips, and read his write up on protected and registered pals. Spoke with him in brief conversation on the conversion too.. its not going to be easy and its well above my abilities.. I will continue to try and source a second physical chip - all while seeing if I can find someone with the skill and time that might want to take on this beast and attempt to do the actual cracking.
 
Most likely this TIBPAL22V10 is registered but if it's not secured we can read in a normal programmer and then reverse it into a GAL22V10.I've done it many times like in past days when I did a similar thing with a PAL20R8 from Night Striker.Chip was obviously registered but unsecured so I have reversed it in a GAL22V10 fuse map and then succesfully tested the dump back on PCB.If someone with this Cruisin' USA can check if pin 13 of this 'A-19993.U38' is tied to GND (and pin 1 to a clock or strobe signal).This will tell us if the chip is really set as registered.
 
A multimeter to check is pin 13 is tied to ground.A scope if pin 1 is tied to a clock signal.But the pin 13 check can be enough.
 
Update: Thanks to help from Jrok - the chip has been decoded and reproduced successfully.. I have a few of the kits now available for sale and I have released the source to jammarcade.net for publishing in April. If you need any of these chips or kits to link let me know.. and the decrypted gal will be released by jammarcade soon..

Thanks all for your help and willingness to participate.

- Rick
 
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