What a *hell* of hack!...
Long time ago, I started a real "hunt" for these kind of rare boards. Truco Clemente was one of the most "hard to find" PCBs. Two BIG trips and a lot of time/money were involved in this hunt.
The first board I found, was through a friend that pointed me where the machine was located.
The PCB was basically a pacman hardware with an additional board.
After some negotiations, the owners (a big arcade in the atlantic coast of south america) allowed me
to dump the roms. Unfortunatelly I didn't found bipolar proms, except the original pacman ones.
I offered them to buy the board, but they refused at the beginning, and unfortunatelly
some months later the PCB was destroyed with a lot of other old jewels (as a black-background Astro Fighter)
"to make room", they said.
Some years later, a 2nd board appeared. Another friend was involved in the hunt and after a hard work
against a technical lab and a collector, we finally got the (in)famous PCB... (thanks, Chris!).
This time the "hidden" bipolar proms were located in the daughterboard. (see "Technical bits..." below)
Bipolar proms are inside the daughterboard, in the same place where
the hidden ones (from the 1st board found) were located.
To clarify a bit:
1st board found ----> daughterboard ----> location 1 = ls74xxx (scratched to avoid recognition)
1st board found ----> daughterboard ----> location 2 = ls74yyy (scratched to avoid recognition)
2nd board found ----> daughterboard ----> location 1 = 27s19 (clearly readable)
2nd board found ----> daughterboard ----> location 2 = 27s19 (clearly readable)
Since neither of my programmers can read bipolar proms, I carried the
board to a laboratory to read these two 27s19's.
Here are 2 different views from the PCB. (click to enlarge)
Details of the hack...
Wires from 74ls377 (at loction D2)
pin 19 ---(daughterboard)---> pin 02 eprom 27c010 (02)
pin 16 ---(daughterboard)---> pin 14 bipolar 27s19 (u2)
pin 15 ---(daughterboard)---> pin 29 eprom 27c010 (02)
pin 12 ---(daughterboard)---> pin 28 eprom 27c010 (02)
pin 11 -----------------------------> * D3 (top), pin 11. (this means they are clocked together)
pin 09 ---(daughterboard)---> pin 04 eprom 27c010 (02)
pin 01 -----------------------------> * D3 (top), pin 02
* At location D3 there are 2 ttl soldered one on top of another. Both were scratched to avoid recognition.
Scary, huh??
detail of the original *SOLDERED* bipolar prom. ;)
The main PCB is basically the same Pacman bootleg jamma board found in
Mowerman's site under the title of "Bootleg Pac-Man JAMMA #1".
See the detail of "Made in Greece".
For your reference, in the following pic you can see 3 groups of resistors RA, RB, and RC
(4 resistors each, numbered from left to right). So, RB3 is the 3rd resistor from group RB.
Gals are numbered as G1, G2, G3.
Roms are numbered as ROM 01, ROM 02, ROM 03.
Connector (pinout) are numbered from bottom to top by connection.
I think 1&2 are gnd, 3&4 are +12v, 7&8 are red & blue, and 7b (same position,
but from solder side) are green. Correct me if I'm wrong.
27s19 (U1)
----------------
pin 01 ----> (daughterboard) RA1 (2.2K) ------------------------------> connector 7b (green component).
pin 02 ----> ??? n/c. Maybe was (daughterboard) RA2 (1K) ----> connector 7b (green component).
pin 03 ----> (daughterboard) RA3 (410 ohms) -----------------------> connector 7b (green component).
pin 04 ----> (daughterboard) RA4 (220 ohms) -----------------------> connector 7b (green component).
pin 05 ----> (daughterboard) RB1 (2.2K) ------------------------------> connector 8 (blue component).
pin 06 ----> (daughterboard) RB2 (1k) ---------------------------------> connector 8 (blue component).
pin 07 ----> (daughterboard) RB3 (410 ohms) -----------------------> connector 8 (blue component).
pin 08 ----> GND.
pin 09 ----> (daughterboard) RB4 (220 ohms) -----------------------> connector 8 (blue component).
pin 10 ----> (daughterboard) G1 ----> pin 19.
pin 11 ----> (daughterboard) G1 ----> pin 18.
pin 12 ----> (daughterboard) G1 ----> pin 17.
pin 13 ----> (daughterboard) G1 ----> pin 16.
pin 14 ----> (main) D2 (ls377) ----> pin 16.
pin 15 ----> GND.
pin 16 ----> +12v.
27s19 (U2)
----------------
pin 01 ----> (daughterboard) RC1 (2.2k) ------------> connector 7 (red component).
pin 02 ----> (daughterboard) RC2 (1k) --------------> connector 7 (red component).
pin 03 ----> (daughterboard) RC3 (410 ohms) ----> connector 7 (red component).
pin 04 ----> (daughterboard) RC4 (220 ohms) ----> connector 7 (red component).
pin 05 ----> ??? n/c.
pin 06 ----> ??? n/c.
pin 07 ----> ??? n/c.
pin 08 ----> GND.
pin 09 ----> ??? n/c.
pin 10 ----> (daughterboard) G1 ----> pin 19.
pin 11 ----> (daughterboard) G1 ----> pin 18.
pin 12 ----> (daughterboard) G1 ----> pin 17.
pin 13 ----> (daughterboard) G1 ----> pin 16.
pin 14 ----> (main) D2 (ls377) ----> pin 16.
pin 15 ----> GND.
pin 16 ----> +12v.
GAL16v8b (G1)
-------------------
pin 13 ----> 74ls161 (at location C12), pin 07.
pin 14 ----> 74ls10 (at location C11), pin 04.
pin 15 ----> 74ls74 (at location C10), pin 06.
pin 16 ----> 27s19 (both) ----> pin 13.
pin 17 ----> 27s19 (both) ----> pin 12.
pin 18 ----> 27s19 (both) ----> pin 11.
pin 19 ----> 27s19 (both) ----> pin 10.
Some investigation with Dave Widel... (thanks Dave!)
The driver says there's 16 bytes to a tile. So that's 2 bits per pixel. That means there's 4 colors to a tile, just like pacman. So I combined the color proms and looked at the palletes. It doesn't really make sense to me. I would expect it to be divided up into groups of 4. The second line makes no sense at all as a pallete it seems to be a color bar from black to white. The first line doesn't make sense either since pallets normaly repeat one of the colors.
rbg
000 555 999 009 - 55f 900 f55 090 - 5f5 905 f5f 990 - ff5 099 f5f fff
000 111 222 333 - 444 555 666 777 - 888 999 aaa bbb - ccc ddd eee fff
From Dave Widel: "The values in the color rom are at least as many as 6 bits. If the lower 3 or 4 bits are used to bank switch the graphic rom then there's 2 or 3 bits left to select a pallete, but I have to admit I don't see it. The fact that it goes through a gal makes it difficult for me to figure it out. You've hooked up the outputs the way I'd have done it. I think your going to have to talk to someone that works with colors more though. I don't ever have to work with them since the color system for pacman never changes."
One thing that does look wrong though is the screen map. It's simple
consecutive, it almost certainly should be pacman style. 4000-403f and
43c0-43ff go on the short ends not the long ends.