> > Hi everyone! First post here!
> >
> > I recently bought a bundle of Jamma boards, with those came a MegaPlay with 3
> > carts and a System Multi 32(huge beast!).
> >
> > Can anyone give me any aditional information or manuals for these PCB's?
> > The MegaPlay has about 9 sets of conectors which I have no idea what they are
> > for!
> > The MegaTech used a 2nd monitor, does the MegaPlay also use one?
> >
> > The MegaPlay board worked fine when I first tried it but after I swaped the
> cart
> > order it stopped working! It powers on but doesnt boot the game, the screen
> just
> > stays black.
> > If I remove all carts I get to some sort of BIOS screen which says 'insert
> > cart'... Any ideas?
> >
> >
> > About the System Multi 32, can I run it with just one Jamma harness conected
> or
> > do I need to connect both at once for it to work?
> > Also, what are those optical terminals and that weird port between the jamma
> > harnesses for?
> >
> > I hope you guys can help me out...
> >
>
> try making sure the cartriges are inserted properly as the this can stop games
> from loading. also try cleaing the contacts with a cotton bud with a small
> amount of water as this does get games working. this also works on neo
> geo/megadrive/master system an other cartrige based hardware.
>
> the megaplay hardware only works with megaplay games and not megadrive games.
>
> hope this helps
>
> retromad2
>

That was the first thing I did, both the slots and carts are clean, they are MegaPlay carts.
Because I didnt have the select button wired and I wanted to change game I powered off the board and swapped the order of the carts.

It never worked again. Seems as it doesnt find the BIOS on the carts, however it goes to the internal 'insert cart' screen if no cart is inserted.
I tried removing the battery hoping that it could clear the internal memory and solve the problem but I had no such luck.

I remembered one thing, my setup doesnt have the -5v connected, anyway it worked before without the -5v so that shouldnt be the problem I guess...
-5v on the harness is normally used to power the audio amp, right?