Dumping questions

[van_halen]

I bought a Game Doctor SF7 a while ago to be able to back up some prototype stuff. However, a few of them refuse to dump correctly, Pilotwings among others. The emulator says the checksum is bad, but it loads up and plays fine until the start of any simulation part. From there everything gets black and only the music and sounds are playing. I'm fairly sure the DSP is not the final version, which might explain it all. If so, will that automatically render the checksum bad even if it actually is a good dump?

Also, if I were to dump the contents of the DSP, is it possible to somehow do it without having to desolder it from the board?

http://farm8.staticflickr.com/7029/6526780039_a5e768948b_z.jpg (http://www.flickr.com/photos/15364636@N06/6526780039/)

[badinsults]

It is entirely possible that the Game Doctor SF7 might not be able to handle the mapping of the prototype carts, especially a DSPx game. Personally, I would suggest getting a Retrode, it should be able to dump any non-SA-1 game. I might not be the best person to ask about such things. I suggest asking on the SNESfreaks (http://forum.snesfreaks.com) forum. They have several SNES hardware experts who would be able to help you out (don't worry about the fact it is a German forum, they will be able to help you in English).

[Vectorman0]

It is entirely possible that the Game Doctor SF7 might not be able to handle the mapping of the prototype carts, especially a DSPx game. Personally, I would suggest getting a Retrode, it should be able to dump any non-SA-1 game. I might not be the best person to ask about such things. I suggest asking on the SNESfreaks (http://forum.snesfreaks.com) forum. They have several SNES hardware experts who would be able to help you out (don't worry about the fact it is a German forum, they will be able to help you in English).

You should listen to this guy.

[Jorpho]

You should also mention what emulator you're using. Have you tried BSNES?

[badinsults]

If the DSP1 chip is not the same as final, you might have to dump the contents of the chip for it to emulate properly. BSNES does have the facilities in place to emulate it if the prototype DSP1 image is dumped.

[Jorpho]

I should add that if http://byuu.org/articles/decap is any indication, dumping the DSP image is non-trivial.

[byuu]

If the DSP's program/data ROMs are truly unique ...

The data ROM can be dumped via software command (you'd need something like a DX2 and a special program.) The program ROM may be dumpable via external reader, if the read-protection is not enabled.

All official DSP-n chips had read-protection enabled. If that's the case, your last option is to decap the chip, and dump the ROM via hacking the chip up. Basically only Dr. Decapitator is capable of this, and it will destroy your chip forever. It's very unlikely to succeed on a single chip as well, it usually needs 4-5 donor carts. And it costs a whole lot of money for all the materials and equipment needed.

So your best bet is to try it with the DSP-1 first official revision firmware under emulation. Failing that, I'd just give up on running it under emulation.

[van_halen]

Thanks for all the info.

byuu: I see. To check whether or not read-protection is enabled, is it possible to put a clip or something over the chip and connect it to whatever device can read it? I wouldn't want to tamper with the stuff too much. Otherwise, I think I'll have to give up the thoughts on emulating it properly. Seems to be mostly minor differences in the game from what I have seen.

Just for the record, the equivalent to the "4-Line Digital Demultiplexer" (no idea what it is or what it does) seems to be stored on the EPL16P8BD[possibly some more] chip with a white sticker covering it. A search brings up that it's a "Ricoh CMOS Electronically Programmable Logic", so I guess there's a risk that even that one doesn't contain the final code and might need to be dumped in order to emulate the game.

J'orfeaux: I'm currently using Snes9x, but I will try BSNES as soon as I get some days off.

Evan: Yeah, I've had plans on getting a Retrode 2 as those seem so user-friendly and portable. Might at least do the trick with the other ones that keep failing. Definitely worth a try and it would be great to have anyway.

[Edmond Dantes]

I just noticed you're trying to dump a PROTOTYPE cart. Could that, possibly, explain why the rom image doesn't quite play right? Because it's an unfinished version of the game?

[badinsults]

Just for the record, the equivalent to the "4-Line Digital Demultiplexer" (no idea what it is or what it does) seems to be stored on the EPL16P8BD[possibly some more] chip with a white sticker covering it. A search brings up that it's a "Ricoh CMOS Electronically Programmable Logic", so I guess there's a risk that even that one doesn't contain the final code and might need to be dumped in order to emulate the game.

I imagine if the DSP is on a programmable logic chip, it might be possible that the program is not read-protected, and might be dumpable with a programmer. But again, I'm not the expert on this, and I suggest getting a hold of d4s (who is on the SnesFreaks forum I linked earlier). The demultiplexer chip simply splits the signal (probably the inner workings of the DSP) into individual components.

[AceAerosmith]

OK, I got lured by the "Dumping". Wrong dump. Sorry. I'll just see myself out. Thanks.

[van_halen]

I imagine if the DSP is on a programmable logic chip, it might be possible that the program is not read-protected, and might be dumpable with a programmer. But again, I'm not the expert on this, and I suggest getting a hold of d4s (who is on the SnesFreaks forum I linked earlier). The demultiplexer chip simply splits the signal (probably the inner workings of the DSP) into individual components.

Sounds like a possibility. I'll contact him shortly and see what he thinks.