Topic: Poorly Space Invaders Cab  (Read 4244 times)

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Offline Rimmo1

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Re: Poorly Space Invaders Cab
« Reply #15 on: July 27, 2011, 04:39:33 PM »
Yes the pattern is the same every time you turn it on

Offline Womble

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Re: Poorly Space Invaders Cab
« Reply #16 on: July 28, 2011, 01:29:13 AM »
Could a Z80 (instruction compatible) be "persuaded" to run in that? Just in case it does need replacing?

Not with any great ease I'm afraid, there is alot of support circuitry around the 8080 that is built into the Z80 so you would need to work through the schematics and find a way to disable that and bypass it with the Z80s output. Secondly the Z80 is only 8080 compatible in a certain mode which I believe is set through a software call, so you would have to hack the ROMs and then adjust all the code call points to deal with any resulting offset. Basically it is not worth the effort as 8080s are readily obtainable, anyway it is highly unlikely that the 8080 is bad, it is probably either lacking clock or is held in reset. Thirdly a SI cab in this condition with a working board is worth a lot of money, easily over £1500, possibly even higher, it would be criminal to hack the board.

I would suggest Rimmo1 joins aussiearcade.com.au (not just because its my local but mainly because it seems to be one of the more technical arcade sites out there) and send a PM to a member called VectorGlow, he is UK based and does board repair.
Sic Transit Gloria Atari

Offline resident paul

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Re: Poorly Space Invaders Cab
« Reply #17 on: July 28, 2011, 10:24:46 AM »
Take a few close-up photos of the circuit board so the experts help out a bit more.
No harm in doing that! :)

Offline Rimmo1

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Re: Poorly Space Invaders Cab
« Reply #18 on: July 28, 2011, 10:44:47 PM »
Hi
I am away for a few days. I can post some more pics when I get back.
Thanks for everyone's help
Rimmo1