[May/31/98]

                     Video Game Chips on Disc           11/02/97


Name   Type   Position    Rev     Checksum   Marked     Notes
*------------------------------------------------------------------------------
Lizard Wizard
       63S141   4A                  0A8B     4A         Pac Man Conversion (need
       63S081N  7F                  1697     7F         Pac Man Conversion (need
       2532     5E                  C511     5E         Pac Man Conversion (need
       2532     5F                  D55D     5F         Pac Man Conversion (need
       2532     6E                  F3FF     6E         Pac Man Conversion (need
       2532     6F                  1CFF     6F         Pac Man Conversion (need
       2532     6H                  F6FF     6H         Pac Man Conversion (need
       2532     6J                  48FF     6J         Pac Man Conversion (need

Okay I used a cutoff saw to trim down the Epoxy block & used a blow torch to melt away
most of the goo.  From that I wired up an adapter that the 40 pin ribbion cable
plugged into, grabbing all the Address & Data lines and reading the whole thing as
a 27512 format EPROM.

There are 2 2732 EPROMs in the epoxy block.  I refer to them as WizA and WizB.

When I read the whole thing, it appears that WizA is at $4000 and WizB is at $5000,
somewhat different from Ms Pac but that may have something to do with the other
circuitry that toggles them.  The other circuitry consisted of 2 chips,
one a 74ls32 with only one gate used.
The inputs were A15 and MREQ but for the life of me I could not find where the output went.
The other chip I cannot ID, they are using it as the select (Chip Enable) for the 2 ROMS.
The mystery chip has inputs of A12 and MREQ but I did not find any other inputs
(seems like the ouput of the 74ls32 would be here?).


Anyway....

WizA checksum is 3F90
WizB checksum is 06F2

WizA read easily at +5VDC, WizB was not very cooperative (might have been the blow torch)
but I finally got a consistent read at a low voltage, about 3.8 VDC
(I've used this trick before on other weakend ROMs with good results).

This will run as Mspacman on MAME using WizA as boot5 and WizB as boot6.
The colors need to be fixed and I belive there is another input line.
I have the complete kit plus docs, which I'll retrieve asap.


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