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 Size differences...who's right?
 
Argument: ROM data , Closed by: root
techdesign @ 2009-01-20 04:17:46

Okay, finally getting around to "auditing" my roms to make sure I have valid sets. I really like the concept of no-intro, so started using it to rename my ROMS and such with clrmamepro.

Now I hit the Colecovision (with fond memories). My ROMS, which check out fine with GoodCol, have some issues with the no-intro DAT. Several of them don't check out. I've ripped my hair out for a day about this, and finally started digging around with just one problem ROM - Alcazar, the Forgotten Fortress. The ROM I have checks fine with Good, TOSEC and a few other DATs I've found, but not with no-intro--the CRC just doesn't match. I was getting ready to check "endian-ness" and byte-swapping after reading a few other posts...

Finally, I realized the expected file size for no-intro is 32768, giving a CRC of 52b61431. Every other DAT/checking tool I've tried expects a file size of 16384, with a CRC of 9cc3fabc. This just happens to be the ROM I have of course.

So now, this begs the question of why? Why does no-intro expect a file exactly double the size of the ROM I have? Which one is right? The 32K ROM or the 16K ROM? I can't find reference anywhere to two versions of the game. I expect this is going to be the issue with the other ROMs I have when I get a chance to check them out later.

Thanks for any enlightenment anyone can shed on this as I learn this process!
techdesign @ 2009-01-20 04:56:05

Okay, kind of answered my own question. I did find a listing of Colecovision ROMs, and on that listing, it show Alcazar as a 32K ROM.

http://classicgaming.gamespy.com/View.php?view=ConsoleMuseum.Detail&id=25

But still it makes me wonder what, if anything, I'm missing with my 16K rom. Was the other 16K just empty? I've tried padding my file with 16K worth of FF, but that doesn't get me to the same CRC...