Afterburner graphics issues

debaser138

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I picked up an Afterburner that works but most of the graphics are missing during play (can't see your plane, other planes, background, etc. Pretty much all you can see is a horizontal line for the horizon. Alot of the text is also really hard to read.

I was able to get the shaker motor working by replacing the fuse and putting the fuse cap holder back on which I found in the bottom of the cabinet (love those easy fixes!).

I was able to get into test mode and it's complaining that IC125 is bad (verified this by looking at this test screen in MAME since the text was impossible to read on the game).

The markings on this chip are MB81C78A-35P-SK. It's an 8KX8 CMOS 28 pin SRAM. Anyone know where I can get one of these?

Also, I did a dump of all the ROM's on the board to make sure they were good. The weird thing is two of the ROM's which are marked EPR-11109 and EPR-1110 both came up as unknown with ROMIdent. All the other ROM's checked out.

So I thought these were bad. I have another non-working Afterburner board so I pulled those two ROM's from that board and dumped them and checked them with ROMIdent. They both came up as unknown. The respective chips from board A have the same checksum as the chips from board B so I'm pretty sure the ROMs are good.

I downloaded the MAME ROM images for Afterburner 2 and they compare to mine except for those two I mentioned above. Anyone have any more info regarding this?
 
i ahd the same problem too with my afterburner. Though it wasnt as bad as what you described. I had lines going thru the refueling plane and in some other scenes. Lines that shouldnt be there.

I started by removing the control board, which was incredibly dusty. In many cases dust bridged the gap between legs on the chip sockets.

I removed and reinstalled every chip one by one. I then, held my breath (and I dont take responsibility for any issues that occur), and lightly sprayed down the entire board with water.

Yes water, to dissolve and wash away any dust.

I used a blower dryer to dry it all. When I reinstalled it, everything worked perfect. Perfect graphics.

Id start first with removing and reinstalling every chip into its socket - to ensure corrosion or dust bridging isnt causing a short somewher.e
 
i ahd the same problem too with my afterburner. Though it wasnt as bad as what you described. I had lines going thru the refueling plane and in some other scenes. Lines that shouldnt be there.

I started by removing the control board, which was incredibly dusty. In many cases dust bridged the gap between legs on the chip sockets.

I removed and reinstalled every chip one by one. I then, held my breath (and I dont take responsibility for any issues that occur), and lightly sprayed down the entire board with water.

Yes water, to dissolve and wash away any dust.

I used a blower dryer to dry it all. When I reinstalled it, everything worked perfect. Perfect graphics.

Id start first with removing and reinstalling every chip into its socket - to ensure corrosion or dust bridging isnt causing a short somewher.e

Already cleaned/reseated all of the socketed chips when I verified all the ROMs.

I'm pretty sure I just need to replace that bad RAM chip to fix my graphics issues but I'm having a hard time locating it. I may have to resort to robbing it off my non-working Afterburner board but I don't have any way to know if that one works or not as that board is completely dead.


Rodney
 
Afterburner Upright graphics issue

Already cleaned/reseated all of the socketed chips when I verified all the ROMs.

I'm pretty sure I just need to replace that bad RAM chip to fix my graphics issues but I'm having a hard time locating it. I may have to resort to robbing it off my non-working Afterburner board but I don't have any way to know if that one works or not as that board is completely dead.


Rodney

I am having a similar, but different problem. I am getting "ghost" images of scaled sprites. Things that are plain text (like the score) are fine, but anything that zooms or rotates has artifacts. It's a different error than here http://dweeb.net/afterburner/badrom/ but I havent had the time to check it out. I remember seeing games like Thunderblade and Space Harrier with the same problem. Monaco GP has the same hardware too (I think). The game is playable. I have run it for hours with no resetting or lock-ups. Thanks!
 

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Now having this exact problem.

I picked up an Afterburner that works but most of the graphics are missing during play (can't see your plane, other planes, background, etc. Pretty much all you can see is a horizontal line for the horizon. Alot of the text is also really hard to read.

I was able to get the shaker motor working by replacing the fuse and putting the fuse cap holder back on which I found in the bottom of the cabinet (love those easy fixes!).

I was able to get into test mode and it's complaining that IC125 is bad (verified this by looking at this test screen in MAME since the text was impossible to read on the game).

The markings on this chip are MB81C78A-35P-SK. It's an 8KX8 CMOS 28 pin SRAM. Anyone know where I can get one of these?

Also, I did a dump of all the ROM's on the board to make sure they were good. The weird thing is two of the ROM's which are marked EPR-11109 and EPR-1110 both came up as unknown with ROMIdent. All the other ROM's checked out.

So I thought these were bad. I have another non-working Afterburner board so I pulled those two ROM's from that board and dumped them and checked them with ROMIdent. They both came up as unknown. The respective chips from board A have the same checksum as the chips from board B so I'm pretty sure the ROMs are good.

I downloaded the MAME ROM images for Afterburner 2 and they compare to mine except for those two I mentioned above. Anyone have any more info regarding this?

Got another boardset, tested it out, worked great after 4 hours of play so purchased it.
After about 20 hours of runtime in my machine, it started getting glitchy. Next time I started it up, All the scaling GFX are gone. The game thinks that it is playing correctly. All self tests pass. Haven't had time to start pulling chips, but wondered if anyone has found a "smoking gun" for this particular problem. Thanks.
 
basics

So you re-seated and verified the EPROMs, which is good.

Have you checked the voltages of the PS and on the PCB?
Have you re-placed any of the caps like the big filter cap mounted on the base of the cabinet? I ask because this sounds like it could be a power issue due to the fact you seem to have fluctuating results.
 
Pcb

If any game PCB that is hooked up works for a bit and then tanks, I think that's a good indication of a power issue.

Got a spare power supply? Give it a go.
 
Yes, but...

If any game PCB that is hooked up works for a bit and then tanks, I think that's a good indication of a power issue.

Got a spare power supply? Give it a go.

I would be inclined to believe it too, if they both did the same thing. Still, I will put another power supply in there and use the O-scope to check for AC ripple on the old and the new.
Thanks!
 
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