Arkanoid repair tips needed

[sebastius]

I've got three bootleg arkanoid boardsets. One is incomplete, ill skip that one.

 

The first boots nicely, all graphics are there, EXCEPT the paddle, the ball and the random floating aliens that drop in from above. Those are all missing. The game works though, but invisible arkanoid is not really my favourite... And it's a bit difficult to finish.

 

I havent started poking around this one yet.

 

The second boots as well, but the screen has bars from left to right (actually, if you put the monitor in the horizontal mode, its from top to bottom offcourse). Its a bar good picture, a bar random garbage sprites, a bar picture, etc. About eight bars good and eight garbage, i reckon.

 

Things i've tried with the second board: Removing and reseating eproms. Replacing some roms. I tried shorting some adress bits in the vid ram(got garbage on the GOOD part of the screen, but no change in the bad part).

 

If anyone has any experience with arkanoid problems, or recognizes this problem from another game, i'd be very happy...

[Cassidy Nolen]

Sounds like the one with invisible parts just has a bad eprom (whatever one has the graphic data for the game). If it still plays fine, I am assuming its just the graphic data, and I am also assuming they are on one chip. Maybe someone could verify that? Do you have access to check the eprom checksums?

 

The bars is video RAM. Just a matter of figuring out which one. You have two good boards to swap with. If they are like the old-school boards, Ark boards probably have socketed video RAM. If not, would make sense to trouble shoot further before swapping parts out. Check your schematics and find where stuff is. Should be easy fixes on both.

 

Worst case, take the eproms from your jailbar board and fix your other one. Two out of three ain't bad. Wish I could do that with Pole Position and Missle Command boards!!!

 

 

HTH,

Cassidy