Rampart GAL replacements


I had an Atari Rampart board which was fine except for a bad GAL at location 8M, Atari part# 136082-1004. 
Using a known good part I reversed it's function back to equations so as to make a new working replacement. 
Here are the results with both source code, in ABEL format, and the JEDECs. It appears to work perfectly in both
the 2 player and 3 player versions of the gameboard.

For the technically minded this part is a bus multiplexer with 2 control inputs. It controls access to the RAM address 
bus for either the CPU, the motion object ( sprites ) system, 'slips' or motion object controls.

After a request for help with two other replacements it was back to the analyzer to figure out the functions of these parts
and build some equations that would function like the original parts.

The replacements for 12C and 4L were programmed into GAL16v8-25's and tested on both the 2 player and 3 player
versions of the game. The faster -15 and -10 parts will work too and also tested was a PALCE16v8-25.

Board Locations and Part Numbers

Part# Location GAL type Comments
136082-1001 4L GAL16v8
136082-1004 8M GAL22v10 or 20v8
Can be compiled for either 22v10 or 20v8
136082-1006 12C GAL16v8
3 player trackball version 27c512 (64K x 8 ) EPROMS at the locations ROM 0H and 0L
136082-1056 12C GAL16v8
2 player joystick version with 27c101 (128K x 8) EPROMS at the locations ROM 0H and 0L


Source Code JED Files

Rampart PLD source files Zip

Contains ABEL source for PLD's
  • rampart_136082_1001_4L.abl
  • rampart_136082_1004_8M.abl
  • rampart_136082_1006_12c.abl
  • rampart_136082_1056_12c.abl

Rampart PLD compiled JED files  Zip 

Contains compiled JED's ready for programming
  • rampart_136082_1001_4L.jed
  • rampart_136082_1004_8M_gal20v8.jed
  • rampart_136082_1004_8M_gal22v10.jed
  • rampart_136082_1006_12c.jed
  • rampart_136082_1056_12c.jed


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