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GeorgeSpinner

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I recently purchased a Rastan bootleg board.

When the board arrived there were some issues with the graphics.

This thread over at aussie arcades was very helpful (here).

I cleared up the main reason I was having trouble. I had to replace a bad EPROM.

Being a bootleg, I had to figure out which rom belonged on the replacement EPROM.

The issue with it being a bootleg is that the EPROMs are smaller in size than an official Rastan; so there are more of them, and the information is split across them.

After many hours of looking at hex, I was able to construct the correct binary to use. It worked like a charm.

Finally being able to play the game, I sat down for some nostalgic fun.

At the end of level 2, on the boss screen, the foreground elements all DISAPPEAR.

Only the background remains. No score, credits, health gauge, or sprites.

Somehow, I defeated the boss like this.

On the 3rd level, the foreground elements were back, but at different parts of the level they consistently disappear again.

Does anyone have an idea what can cause this?

I have dumped all the EPROMs and I believe they are OK. '

There are some very minor discrepancies, but no more than 1 Byte in any file. I don't believe they are the cause, but I will try to use MAME to verify.

Does anyone know what can cause such a thing to happen? I am out of ideas.

How does 1 even troubleshoot something like this?

Any help is appreciated.

Thanks.
 

GeorgeSpinner

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I resolved my issue by replacing all of the gfx1 category EPROMs.

I have a new issue where Rastan turns green and the board reboots when reaching the midway point of level 5-1.

I have new EPROMs on the way. I plan to replace all of the maincpu category EPROMs.

Hopefully that fixes my final issue.
 

GeorgeSpinner

Student
Joined
Oct 20, 2020
Messages
96
Reaction score
38
Location
Piscataway NJ USA
I resolved my issue by replacing all of the gfx1 category EPROMs.

I have a new issue where Rastan turns green and the board reboots when reaching the midway point of level 5-1.

I have new EPROMs on the way. I plan to replace all of the maincpu category EPROMs.

Hopefully that fixes my final issue.
Just to follow up - I believe all Rastan boards, bootleg or otherwise that don't run revision 1 suffer from this issue.

I purchased an original Rastan and it had the same exact issue.

I upgraded the original to rev 1 and the problem was solved.

I cannot run rev 1 on there bootleg board as the coinage doesn't work for some reason.
 
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