Baby Pac-Man MAME project EXPERT INPUT NEEDED

[koolmoecraig]

I am about to attempt to MAME my Baby Pac-Man machine.

I am going to do it by mounting a separate isolation transformer for the monitor so I can power it independently. Then I am going to have my computer output via the ArcadeVGA card into an SVGA switch box.  I am also going to have the Baby Pac-Man PCB output into the SVGA swtch box.  The SVGA switch box will then output via Ultimarc breakout cable to the monitor. That way I can power the monitor on separately and choose which system to fire up by turning the switch.

Does anyone see any reason why this might not work?

Also, I want to use the stock Baby Pac joystick along with "piggybacking" on the start buttons and top mounted flipper button but I ran into a problem.  I connected up the start buttons to the Ipac last night and fired up the Baby Pac-Man portion to see if it would affect anything and it does in a big way.  The pinball portion of the game was all screwy.  The flippers would fire without pushing the the buttons etc.

I don't mind having to mount new start buttons and I can just disconnect the top flipper button from Baby Pac and use that one for MAME since I use the side mounted flipper buttons anyway BUT what about the joystick?  I was a little lazy and didn't try it last night but if having it connected to both the Baby Pac side and the MAME side makes the Baby Pac side screw up again, is there any way around it? 

Is there a way to switch on/off the wires going to the Ipac so it doesn't make the Baby Pac go all haywire?

Hopefully this makes sense.

Thanks for the input!

[bfauska]

I don't know why/how it is causing problems, so I won't try to help make it stop, but as far a switching control from the computer to Baby Pac and back again you could use relays.  The joystick would work with 1 relay and you could use another relay for up to 4 buttons.  The ground staying connected all the time shouldn't be a problem since it should need a complete circuit to have any effect at all on the system.  If you found a way to trigger the VGA switch with a relay you could control it all from one switch and never know the difference, when you switched to the computer the monitor and buttons/joystick would all switch over and when you switch back they would all switch back.

That's a very generalized idea, but I could be more detailed provided there isn't a simpler solution.  I wonder if putting diodes inline with the ipac button connections would help.  Maybe somebody more savy can chime in on that idea.

[theCoder]

If you do go with relays, I'd recommend going with an on-line electronics vendor.  I just picked up a bunch for $0.78 each. 

Why are you hacking a working classic arcade box?  Why not keep it original, and build a separate Mame cab?  I'm definitely not a zealot on the topic, just curious.

[koolmoecraig]

I'm going to look into the relays.  I won't be hacking it at all.  I will be able to switch between the two and the Baby Pac-Man will be left original.  I'm not hacking up any parts or wires.

[ChadTower]

Just get a cab that is actually suited for MAME. 

[bfauska]

I think the project can be done easily without any irreversible damage to the Baby-Pac.  If you don't have the space for a full time MAME machine the project sounds cool.

[koolmoecraig]

I've already built two MAME cabs out of original machines.  My Q*bert and Rally-X(Vertical and Horizontal).  I am going to sell my Q*bert as dedicated so I want another vertical machine.  I am transferring all of te mame internals.

I think it will be really cool to have it switchable with no visual cues.  I am only interested in putting the 4-way classics on it so it works out perfectly with the current control scheme.