UpScope Arcade Machine issues

The owner of an UpScope Arcade Machine has contacted me to ask about a problem they are having with it.

If you don't know, the UpScope Arcade Machine is based on either an A1000 or A500 motherboard which is connected to a rom daughter board which contains the game roms, so it boots like a real arcade machine from rom chips, but is using an Amiga as its system. Quite cool.

Anyway, the owner has provided images of the motherboard to confirm it is an A1000 321049-01 rev 6 NTSC US motherboard. It is powered from an Amiga PSU. Other information he gives is that the game roms are on the daughter board, plus 3 roms on the motherboard (although he doesn't say what he means by these 3 roms, but you can see the motherboard below to get an idea).

Now the issue. He has checked the correct voltages from the power supply are fine. however when the system is booted the startup game image is perfect, but once the game has started the display is showing garbage over the game image (The third image I've attached below shows the garbage he is referring to).

So, any of you got any ideas what is causing this? What he can test?

He also mentions that he found another Amiga PCB that works halfway, but that is all he has told me.

Any questions to ask him to get more information?

@Harrison: The motherboard on these arcades is indeed an NTSC A1000.
I strongly believe that the problem lies with the ROM daughterboard. I suppose that this is the sole unit they have? If not, tehy should first try a swap with another daughterboard. If the problem is still graphic glitches, then it's the A1000.
However, if they got no spares, they could go around trying the 'true Amiga way'
If you can help them out, an external floppy would come in handy, and together you could try loading a variety of games which will show you that it ain't (or is) a mobo problem.
Wish i were there! :cool:
Now, take 'er to periscope depth!!!

EDIT: You could also borrow the daughterboard, and try it on an ol' OCS machine. It looks like it plugs onto the parallel port of the A1000. Although you could use it on an A500, you'd simply need a gender-changer.

Thanks. I think ruling out the motherboard is going to have to be the first thing to do as it will be very hard to locate another daughterboard. And I think an A500 motherboard will be the easiest solution as the floppy drive from the A500 can also be used for testing.

BTW, what is normally the kickstart version in this machine? Not been able to check yet.

Mate, that would be some detail! You see, they load from floppy..
Now, if this machine -as it seems- has no floppy, it means the Kickstart boots from the ROMs! Not your ordinary Kickstart, perhaps a custom-made one.
The A1000 started off with 1.0 and went upto 1.3 on floppy that is.
Now, this machine is stated to be circa 1986. That was the year i got my A1000, which came with Kickstart 1.1
Here's some more on that machine http://www.arcade-museum.com/game_de...&game_id=10271
I think i once (way long ago) found an UpScope adf image on the net, could be usefull if you try it out on an A500 :-)

first thing I would do is take a magnifying Glass and inspect the whole motherboard for anything that looks out of the ordinary (Caps) burn lines etc.
Yes, its a slow an Tedious job, but the A1k motherboard (NTSC) is kind of a "primitive" PCB and looks to be somewhat hand built. I can't tell buy the picture if it is a reflection but I have circle a chip that looks weird.also check under the metal cover

Second, the ROM's could have experienced "Bit" Rot after all these years. I am not sure how you could check this without having a "Clean" code, but I know that some EPROMS can be subjected to this.

Having done all that, pick up a second mother board (I have 2 here we could swap, but I honestly don't know the working condition) and try swapping it out.

Excellent! Now I know I'm not delusional. About 20 years ago I came across a strange coin-up machine, a rather 'tall' (you could play standing up) and 'slim' cabinet (instead of the commonplace 'short' and 'bulky') in a local arcade room with a rather simplistic game I barely remember a thing about. But I do remember one of the routine messages saying something about a B52 board/system which got me wondering if it was an Amiga 500 underneath. So it must have been one of these UpScope machines :)

Has be tested the daughterboard is correctly connected and the roms are in seated in place etc? Those defects look to me the sort of thing you would associate with a wonky rom connection in a typical ROM loading arcade machine.

I would strongly expect that this machine has no kickstart. Why would it need it? The daughter board probably just contains the software ROMs and machine boots right into it. I would guess that the A1000 was better suited than other Amigas for this kind of application, purely because of the daughterboard option where available. A1000 motherboards could have beaten JAMMA based cabinets to the market. Probably another criminally underexploited market for Commodore.

As an aside, didn't the early hardware hitting coders write their own routines so game could work without kickstart and claim back the 256k WOM?

He has just sent another image of the whole insides of the hardware setup. It actually looks like there are 2 daughter boards now we can see the whole thing. One collected to the sidecar expansion and the other the parallel port. Does that look like that?

Let me know if any of you can spot anything on this one. If for nothing else this is a nice bit of hardware pr0n from such a rare piece of hardware.

BTW, I will pass on the suggestions so far. Thanks for the help. I hope together we can get this arcade machine up and running again. I will ask him to take more pictures and maybe some video if he can get it running.

My guess is that the second board would serve as an interface for the controllers (see periscope). It also looks like the monitor is actually an RGB type, because that's where it gets output from. The rectangle metal shield should be part of the regular video out, inside which is the crystal for the NTSC frequency. Now, the chip noted by quarkx, we should have a closer look at in order to estimate better.
The second board by the way, can still be tested with an A500. Remember, it actually is a Zorro port, just like the A500, just facing backwards! :thumbsup:

I was thinking exactly the same about the second board being a control interface board for the custom cabinet hardware.

I've asked him to take a look at the chip circled by quarkx and hope he will have time tomorrow to take a look.