Craziest pcb ever from 1980, need help

[myPinballs]

Possibly the most random and hard to find pcb ever, but worth a shot i guess. Looking for a working pcb for the game - Attack UFO by Ryoto Electric. The pcb looks like this, which is also the smallest 1980 game pcb i've ever seen. Kind of a neat idea and so small. It uses the 6560 ic from the commodore vic series of computers, a 6502 and a 6821. Plus just to make it even more weird it used YPbPr output (just 3 wires) to the monitor not RGBS. And of course 2708 roms not anything easy to test like 2716 onwards...




Knightmare thing!! Trying to repair the pcb for a customer, but it's just a crazy design and i cant find any schematics or wiring for the game at all! Perfect!! And they even sanded off the main ic part numbers. I mean come on a 6502 is not that hard to identify! lol

So if anyone knows anything about this pcb, or has a working spare (unlikely i know) or a wiring diagram, of just some info on its being etc etc. Please let me know.

Unfortunately it may be the case that this thing is not repairable and i hate saying that!!

 

[dankcomputing]

VIC-I can only do s-video, how is it putting out component?

 

[myPinballs]

VIC-I can only do s-video, how is it putting out component?

Ok, looking at it more the 6560 chip is outputting comp sync/Lumin and comp colour, so the 3rd pin on the video output of this board is gnd i think. I thought it was ypbpr earlier.

So anyone got ideas on how i could input this to a std rgbs crt. Sync is sync i assume, but is the comp colour able to be connected to an rgb signal without conversion

 

[myPinballs]

my other seperate thought with this is , if 6560 ics were availlable and some rgbs circuit could be sorted, this could make a super small ic count space invaders board for a nice project. Reduce the old 2708s to 1 game rom, reduce the 5 rams to 2 etc. Jamma connector on it, built in sound etc

 

[Georgian2]

Sync striper and connect the viseo sognal to green or something. Or juat use a regula TV tonteat

 

[Mc-Q]

didnt the sega-gremlin vic-duel stuff use a vic chip?
try looking at the schematics for carnival and see how they got rgb.

on a side-note, it cant be that hard to fix a 6502 based board - it's a very simple architecture - just make sure you have no shit chipsockets and maybe dump the roms.
is the ram in a socket?

 

[myPinballs]

didnt the sega-gremlin vic-duel stuff use a vic chip?
try looking at the schematics for carnival and see how they got rgb.

on a side-note, it cant be that hard to fix a 6502 based board - it's a very simple architecture - just make sure you have no shit chipsockets and maybe dump the roms.
is the ram in a socket?

Yeah I know how to fix boards lol, but 2708 roms are not simple to check . I’ve got to buy a £200 adapter to test them.. and yeah I’ll swap all the rams if needs be but all 5 are not socketed so it’s about time outlay aswell when you run a business full time..

The info on similar games using the hardware is useful so thanks for this. That type of info is what I was looking for

 

[Lurch666]

I can read and write 2708 eproms.
There's a tester you can build:
https://www.mattmillman.com/project...ammer-for-2704-2708-mcm68764-mcm68766-eproms/

If you don't want to bother building one just for this project,send me the chips so I can test them and replace any bad ones.

 

[Mc-Q]

i made an adapter using 2 chipsockets and some wires,
it reads as a 2716 and i just hook up 12v and -5v that i tapped out of the programmer anyway!

 

[Kingpin]

Yeah I know how to fix boards lol, but 2708 roms are not simple to check . I’ve got to buy a £200 adapter to test them.. and yeah I’ll swap all the rams if needs be but all 5 are not socketed so it’s about time outlay aswell when you run a business full time..

The info on similar games using the hardware is useful so thanks for this. That type of info is what I was looking for

Data I/O programmer (System 19 or 29A/29B for example) and they can be used for bi-polar PROMs as well apart from many (E)PROMs.

Another approach to verify the ROMs and socketed RAM is a Fluke 9xx0 Troubleshooter (and a 6502 pod in this case).

Yet another approach is the Retro Chip Tester and the appropriate adapter for 2708.

 

[Phils Arcade]

I can read and write 2708 eproms.
There's a tester you can build:
https://www.mattmillman.com/project...ammer-for-2704-2708-mcm68764-mcm68766-eproms/

If you don't want to bother building one just for this project,send me the chips so I can test them and replace any bad ones.

That looks great. Haven't seen this one before. Might give it a try.

 

[2k2]

If you can, try tracing the board and come up with some good schematics. I think this board either uses a pre-production MOS 6560 (as the MAME driver says) or it's a regular MOS 6560 with attributes hardwired on the board. Try seeing if a regular MOS 6560 works in here...

 

[dreamseal]

So if anyone knows anything about this pcb, or has a working spare (unlikely i know) or a wiring diagram, of just some info on its being etc etc. Please let me know.

Unfortunately it may be the case that this thing is not repairable and i hate saying that!!

I've been interested in this machine for years now, ever since learning that it had an early version of the 6560 VIC chip. A few years back (2016/17), I was reverse engineering the VIC 20's VIC chip from microscopic photos of the silicon die and I pretty much finished doing that, so I understand how it works internally very well.

The 6560 VIC chip in Attack UFO is different from what was used in the VIC 20. I believe they must have changed the design prior to what they included in the VIC 20. Some of the registers behave differently. I actually wrote an emulator for Attack UFO a few years ago with the purpose of understanding the differences. The 6560 in Attack UFO doesn't support the multi-colour mode, and it doesn't support the reverse mode. Given the latter one, it might mean that it supported 16 border colours (the VIC 20 only had 8, due to the reverse mode bit).

I would be interested to know if you got the machine working, and if not, then what ended up happening to it. I realise it has been many months since you posted above.

 

[myPinballs]

I've been interested in this machine for years now, ever since learning that it had an early version of the 6560 VIC chip. A few years back (2016/17), I was reverse engineering the VIC 20's VIC chip from microscopic photos of the silicon die and I pretty much finished doing that, so I understand how it works internally very well.

The 6560 VIC chip in Attack UFO is different from what was used in the VIC 20. I believe they must have changed the design prior to what they included in the VIC 20. Some of the registers behave differently. I actually wrote an emulator for Attack UFO a few years ago with the purpose of understanding the differences. The 6560 in Attack UFO doesn't support the multi-colour mode, and it doesn't support the reverse mode. Given the latter one, it might mean that it supported 16 border colours (the VIC 20 only had 8, due to the reverse mode bit).

I would be interested to know if you got the machine working, and if not, then what ended up happening to it. I realise it has been many months since you posted above.

Sadly i never got the thing to work and sent it back to the owner. the 6502 just crashed immediately after reset. Early on i thought i found the problem with a bad ram ic, but i concluded the 6560 was dead in the end to even though the clock side was fine. I tried everything including redrawing the entire pcb schematic from tracing every wire on the pcb and buzz checking them so i could study how it worked. I even sourced some other 6561 (pal version) chips at great expense to see if it made any difference scope wise. It did not. I wasn't aware there were register differences on the original/pre-release 6560 ic. What a pita!!

I wanted to make some new pcbs for this game with reduced rom /ram count to make a really nice low ic count space invaders pcb with jamma and rgb out but as the 6560 ic was so unusual i just parked the idea. I also recently thought about an FPGA version of the pcb. The problem was how to make it rgb out as the 6560 ic doesnt even support that i believe, but there was a core for it i think

If you want the schematics then we can chat on dm. I'd love to be able to recoup some invested money and time from this endeavour. It was a total loss in the end business wise. Spent so much time trying to solve it

 

[Lurch666]

Did you ever manage to read the 2708s?

 

[myPinballs]

Did you ever manage to read the 2708s?

Of course. All checked fine

 

[dreamseal]

Sadly i never got the thing to work and sent it back to the owner. the 6502 just crashed immediately after reset. Early on i thought i found the problem with a bad ram ic, but i concluded the 6560 was dead in the end to even though the clock side was fine. I tried everything including redrawing the entire pcb schematic from tracing every wire on the pcb and buzz checking them so i could study how it worked. I even sourced some other 6561 (pal version) chips at great expense to see if it made any difference scope wise. It did not. I wasn't aware there were register differences on the original/pre-release 6560 ic. What a pita!!

I purchased a few 6561 PAL VIC chips in the past, so I know what you mean. Were there no VIC 20 6560 chips available to try? In theory, if all else was well, then a VIC 20 6560 chip would have produced video output, but there would have been graphical differences, such as in relation to the reverse mode. I'm struggling to remember now what my emulator screen looked like prior to me tweaking the emulation of the 6560 part, but it certainly was recognisable. I think it might have been that parts of the graphics were reversed or in multi-colour mode when they shouldn't have been, and that would have been quite ugly to be honest, so not a workable solution.

I wanted to make some new pcbs for this game with reduced rom /ram count to make a really nice low ic count space invaders pcb with jamma and rgb out but as the 6560 ic was so unusual i just parked the idea. I also recently thought about an FPGA version of the pcb. The problem was how to make it rgb out as the 6560 ic doesnt even support that i believe, but there was a core for it i think

Yeah, that's right. The 6560 chip generates one output for the chrominance and one for the luminance/sync. So all the colours are mixed within that analog chrominance output. An FPGA core for the 6560 could be adjusted for the known differences between the VIC 20 design and the Attack UFO design.

Another option would be to change the program ROM code to work with the "standard" 6560 chip.

 

[orac81]

I was also interested in this. The later 6560s have been "decapped", photographed and reverse engineered by vic20 enthusiasts, so that FPGA replacements can be made. Someone has even completely made a 6560 from TTL! If this is a non working chip there is a group of people who would help this user get his machine running, in exchange for a chance to look at this old 6560. As said, a newer 6560 would probably work straight away, (once the rest is working) but the colours would be odd until the code is modified.

 

[QtQ]

This game is listed on Yahoo Auction in Japan as a whole case for your reference.
(But It's too expensive...!)

希少 動作品 音も再生 菱藤電機 アタックUFO イ... - Yahoo!オークション

ご覧いただきありがとうございます今ではほとんど出回るこのないインベーダー風ゲームのアタックUFOです相当昔のゲームですがまだ動作致します音も再生しますただし古いものになりますので注意点など記載致します・電源を付けてから5分以上は消さないでください(故障の原因と

auctions.yahoo.co.jp