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Help dumping Silent Scope comm board mask roms

buffi

buffi

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I have a Silent Scope board which seems to contain the revision dumped in mame as sscopec.

My PCB however has a GQ931 comm board which according to mame should only be fitted on Silent Scope 2. (sscope2 has these dumped as 931a19.8e, 931a20.6e)

This seemed a bit curious to me, so was goign to dump the two mask roms on it, but none of my programmers want to do that nicely, or rather, I don't know what to dump these as.

Dumping as 27c322 gives me every other bytes as 0xFF, after a ignored failed pin insertion test on same pins on both of them.

Silkscreen states MS32M8 for these. 6E and 8E are positions.
Does the M8 there indicate 8bit mode (which would explain the 0xFF bytes?)

Board:
sscope.jpg


Roms in question:
roms1.jpg

roms2.jpg


@rtw : Pinging you here as well, since you know stuff about things
 
Some more googling found me this:
http://members.iinet.net.au/~lantra9jp1_nbn/gurudumps/tutorials/how_to_dump/index.html

"To further complicate matters, there are also 32M MASKROMs that have been programmed in BYTE mode which if read as a normal 27C322, will result in a bad read whereby all EVEN bytes are 00. These are commonly used by Konami for the sound data ROMs. To read these requires an extra read and then interleaving both reads together using some extra software. It's fairly time consuming to explain here, if you have this problem when reading 32M sound ROMs, contact me and I'll explain further :)"

So this seems related (this is a Konami board, and the silkscreen indicates BYTE mode is likely). Anyone know what the exact procedure is?
I'm guessing two reads (as 27c160?), where some pin is tied high/low and then merging the dumps?
 
Interesting. I myself was curious about this too. I thought the game used some strange encryption in the video roms at first until a redump confirmed otherwise.

@Porchy, you have any suggestions because your name was mentioned in that commit.
 
From porchy:

Porchy: He needs to dump as TC5332204
This is the byte version of the 322 eprom
Click to expand...

He could also do it as a 322 by lifting the relevent pin and dumping with it high and low then interleaving.. (I think in byte mode one of the data pins becomes an address pin)
Click to expand...
 
If you don't have support for the TC5332204 @buffi you can send them to me my Elnec supports them.

edit:
sorry that ping never reached me :(
 
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