Wiring a 49way as an 8way - switchable

[SirPoonga]

I know I started this topic before but that was a long time ago.
I have the guts of an arch rivals.  I have a double dragon 2 cabinet with double dragon 1 and 2.  I'd like to have all three in the cabinet (and use something like multijamma).  The obvious problem is what to do with the arch rival 49ways.

I would think it would be a simple circuit to interpret the 49way to 8way signals.  Either a couple of transistors or some IC chip.  Any ideas/schematics?

If the circuit needs an external power source to do the switching I'd have to look at how multijamma works.  I want it to be seamless, no switches.  It will automatically switch depending on the game selected.

[NoOne=NBA=]

The following table shows how one axis' sensors are blocked/unblocked as the stick is moved. "B" is a blocked sensor, "O" is an open (unblocked) one.
<<<    <<    <    center    >    >>    >>>
OOO    BOO    BBO    BBB    OBB    OOB    OOO

Notice the ends: both ends are the same: all sensors unblocked. How does the game know which side it's on? The "side" pin mentioned earlier tracks this on the joystick. The the side pin is added to the one axis table:
<<<    <<    <    center    >    >>    >>>
OOOO    OBOO    OBBO    OBBB    BOBB    BOOB    BOOO

I stole that from Urebel's website.

Using a combo of NOT and AND chips, or just a series of NAND chips, you could set up logic that would detect ALL movement off center (Left=OxxO, Right=BOxx).
It is also possible to set it to detect only second and third stage movement (Left=OxOO, Right=BOOx), or only third level movement (Left=OOOO, Right=BOOO).

For your sticks you will need to invert the output of the axis pins, and then run everything into the AND gates.
Unfortunately, I don't have the time to figure out all the pinouts to connect the two.

The biggest problem may be the connection to the JAMMA harness though.
I'm not sure how the 49-way is connected to the JAMMA harness, so you may need to force the output to different pins on the harness to hook up the two different types of games.
My fear is that the 49-way may be sending its data down the normal stick/button connections, and those signals would have to be interrupted during 8-way games, and the proper filtered signals inserted in their place.

[SirPoonga]

The biggest problem may be the connection to the JAMMA harness though.
I'm not sure how the 49-way is connected to the JAMMA harness, so you may need to force the output to different pins on the harness to hook up the two different types of games.
My fear is that the 49-way may be sending its data down the normal stick/button connections, and those signals would have to be interrupted during 8-way games, and the proper filtered signals inserted in their place.

This is where I'd have to know a little more about how thhe multijamma works.  If I spliced the 4way pins to both the 8way circuit and to the arch rivals board what will happen.  This is where maybe some transistors might be needed to automatically turn on and off some pins depending on what is selected.

[Kremmit]

Arch Rivals needs a Medium Res monitor- Double Dragon 1&2 use Standard Res.  You got a monitor that can handle both?

[SirPoonga]

Hmmm, that puts a kink into things.

[MonMotha]

What you want to do is map all of the 49-way outputs to 8-way outputs (or 4-way, if you prefer).  This can be done with a bunch of combinational logic.  Draw a 49-way grid, figure out what mapping you want to the 4 output signals, come up with a Karnaugh Map for that, minimize it, and implement with 74 series - OR - write some HDL and synthesize it to a PLD.  Should fit on a GAL22V10 or thereabouts.

Oh, if you'd like, I can whip this up for you for a few bucks.

[rockin_rick]

Did you ever try this?

http://forum.arcadecontrols.com/index.php?topic=62392.msg619578#msg619578

Rick

[AaronGiles]

Arch Rivals needs a Medium Res monitor- Double Dragon 1&2 use Standard Res.

Does not!

Arch Rivals uses a standard resolution monitor.

[SirPoonga]

Arch Rivals needs a Medium Res monitor- Double Dragon 1&2 use Standard Res.

Does not!

Arch Rivals uses a standard resolution monitor.

I looked it up in the manual, it uses medium res.

[Kremmit]

Arch Rivals needs a Medium Res monitor- Double Dragon 1&2 use Standard Res.

Does not!

Arch Rivals uses a standard resolution monitor.

I looked it up in the manual, it uses medium res.

Funny, I just had a look in the manual at: 
http://www.basementarcade.com/arcade/library/manuals/a/ArchRivals.pdf
..and it looked to me like Aaron was right and I was wrong.  KLOV says standard, although they've been wrong before.  Still, I was convinced enough that I even went and edited a few old posts of mine where I was telling people it was medium res. 

But I know I got that medium res idea somewhere, and now you say your manual says medium?  Very confusing.  

Aaron, since you're you, I'll assume the version of Arch Rivals in MAME is definitely running standard res.  Now I'm wondering if there's another version of the PCB out there that outputs medium.  Or maybe just some copies of the manual that are incorrect. 

[SirPoonga]

mame sys it is doing 512 by something.