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Sega whitestar cpu 5v ground short?

Anyway, measure resistance between the fused side of F21 and 5V - that may be the culprit. Don’t replace F21 until it is clear there is no short.
 
drhex said:
Anyway, measure resistance between the fused side of F21 and 5V - that may be the culprit. Don’t replace F21 until it is clear there is no short.
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Thanks, ste will get that checked , would still have thought the logic fuse would have blown in x files after all those chips fried!

I have all the known bad chips removed ready for new sockets so some 20 chips if the 2 sound roms are also bad

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Nice collection! We don't know how this happened exactly, maybe on shutdown somehow, stored energy in the caps may be enough to blow the chips, path to ground is via the ground link, will therefore not blow the 5V fuse.
 
So Having checked the intact pal which was in a socket it's also bad, so all 3 pal chips and I just tested all the roms all 4 are bad so 3 sound and the cpu chip on my programmer

Dowloaded the rom set from the pinball database, is this the latest set?

This directroy has the ROM data for Sega's X-Files.
Taken from Jim's working games 11/05/2000

MPU U210 "The X-Files U210 CPU 3.03 $A2FF" 27C1001-10F[A2FF]
Disp ROM 0 "The X-Files Disp ROM 0 A3.00 $66D0" 27C040-12 [66D0]
Snd U7 "The X-Files Snd U7 8/21 $6648" 27C512-15F [6648]
Snd U17 "The X-Files Snd U17 8/20 $549D" 27C040-12 [549D]
Snd U21 'The X-Files Snd U21 8/20 $629C" 27C040-12 [629C]

" " Indicates exact wording on factory chip labels

Also the files for pal chips have JED and and PLD format do I burn these as JED?

Thanks Ronnie
 
Two different formats, you need to open them as .pld or .jed and burn them. I rarely say this but this board was toast. Repairing it may be fun (if you like to solder and mess about with electronics) but not economical. Let me know if you need help in burning any chips.
 
drhex said:
Two different formats, you need to open them as .pld or .jed and burn them. I rarely say this but this board was toast. Repairing it may be fun (if you like to solder and mess about with electronics) but not economical. Let me know if you need help in burning any chips.
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I know what your saying it's a heap of work but worth saving hopefuly !

I have burnt rom chips and some gal's but they have been bin files so not sure how that differs? I hope these pal's are able to be erased in case I fluff it!

Thanks Ronnie
 
Just try to open one - should also be in the documentation of the software. What are you using?
 
It's a Wellon VP-280, I loaded U213 into the buffer no problem then saved it back to the computer, it saved as a binary file, I will try to attach it here to see if it looks correct
 
Manual says it has an integrated editor for jedec files which would suggest it knows them. And further on it says that PLDs need to be programmed using .jed - think you'll be OK.
 
drhex said:
Manual says it has an integrated editor for jedec files which would suggest it knows them. And further on it says that PLDs need to be programmed using .jed - think you'll be OK.
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Perfect, thanks could not attach the buffer file but here is a screenshot of it in the software
 

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The only stumbling block could be the custom BMST sound chip, would it be safe to test this chip in a working machine?

Thanks Ronnie
 
Haven't looked at the schematics but if there is no voltage but 5V on the board it can't really do anything untoward.
 
Just a quick update,

Ste has managed to source a replacement board, it's thought to be faulty! It's missing both cpu's and the BSMT chip, cpu's is not an issue I have some spare (not from fried board)

So I just tested the BSMT chip in working pin and it's bad! not only no sound but after a few secs display went blank.

I know this chip can be written to an eprom and I found a link to the mame source code for the chip but other than that I'm not sure if it can be done easily or not

link to page with source code handwiki.org/wiki/Engineering:BSMT2000

Thanks Ronnie
 
Nope, can't replace the BSMT2000 with an EPROM. This is a DSP with a masked ROM inside. You will have to find a replacement I am afraid.
 
drhex said:
Nope, can't replace the BSMT2000 with an EPROM. This is a DSP with a masked ROM inside. You will have to find a replacement I am afraid.
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Ah ok thanks that's not so good, Would the cpu board run without this chip fitted? That would help to get a working board whilst looking for a replacement

Thanks Ronnie
 
Afaik the sound board section is a separate CPU - so should run just fine. If the board you tested in was running with the broken chip it probably will run without.
 
Yes, you can buy a programmable DSP and burn the code into it - but that requires the code in a format working with the specific chip and the empty DSP. The original has a masked ROM so is done in the factory with the code. Now SEGA did an emulator later on which makes me think that the programmable DSP route was deemed too expensive.
 
drhex said:
Yes, you can buy a programmable DSP and burn the code into it - but that requires the code in a format working with the specific chip and the empty DSP. The original has a masked ROM so is done in the factory with the code. Now SEGA did an emulator later on which makes me think that the programmable DSP route was deemed too expensive.
Click to expand...

Ok thanks, I thought it might not be simple, I guess the only option is to order one as in the link and hope it's ok.
 
So the replacement board has arrived, nice clean board, just the ram socket has a couple of corroded pins so I replaced that and the game Rom socket,
the spare cpu chips I have are EF6809P but the chips on the board were EF68B09EP I’m not sure if these will be compatible ?

Thanks Ronnie


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