Changing the Disc ID

For any serious custom discs, the disc ID is an important bit to change. Without it, you'll corrupt any stock saves that might be on the memory card you're trying to use. Plus, it's just a unique bit of polish for if someone keeps your ISO around. disc IDs are pretty simple to change, consisting of a DTB tweak, renaming the executable, and changing the executable SYSTEM.CNF tries to load when the game starts.

To explain what the disc ID is, it's an internal shorthand that the PS2 uses to keep track of games. It consists of a four letter symbol that identifies the region and purpose of the disc and then five numbers. You'll need it if you're using Sony's CD/DVD Generator, where it's referred to as "Disc Name". Here's some of the NTSC GH2-related disc IDs in existence:

SLUS_214.47 - GH2 Final
SLUS_291.98 - GH2 Retail Demo ("30-song")
SCUS_975.38 - OPM Issue 110 (with the four-song demo)
SLUS_215.86 - GH:80s

Funny enough though, the letters and numbers can be absolutely anything you want, as long as they follow that pattern of four letters and five numbers. For my custom discs, I use the MARF prefix with 0xxxx being the released discs, 1xxxx being demos, and 3xxxx being testing builds of marfGH. You can get as granular or as basic as you like, just pick something no one else is likely to use.

Renaming the executable

So first, rename the executable in the disc root. You have a simple 8.2 filename, with the last two digits of the disc ID as the file extension. I'll be using the marfGH demo disc ID, which is MARF-10002. So we go from a stock NTSC GH2 disc's listing looking like:

To:

The stock GH2 layout after renaming the executable

Changing the `SYSTEM.CNF` to point to the renamed executable

Secondly, open up your disc's extracted SYSTEM.CNF file in a text editor. It's plain text, no need to worry. You'll see three strings.

BOOT2 = cdrom0:\MARF_100.02;1
VER = 1.00
VMODE = NTSC

You'll want to change the disc ID in the BOOT2 string to match the renamed executable.

Changing the save name in the ARK

This is the hardest part, but it's actually a good first change to do if you're learning how to use dtab. Have that installed and know how to tokenize and detokenize a script. Extract mc.dtb from your ARK's config/gen folder. Convert it to DTA. Here's what the first four lines of the file will look like:

(base_dir
   "BASLUS-21447")
(elf_name
   "SLUS_214.47")

(base_dir
   "BAMARF-10002")
(elf_name
   "MARF_100.02")

And of course, convert back to DTB and slot it back into your ARK.

Now, when you go to rebuild the disc using CD/DVD Generator, you'll want to put in your custom disc ID for the Disc Name instead of the default GH2 one.

PCSX2 booting up a custom disc with a custom ID

If you did it all correctly, PCSX2 will report the new Disc Name in the title bar, and it'll take up its own save slot on your memory card.

[2:26 PM] LocalH: An extra "cherry on top" note - if one uses OPL on a hardware PS2 to launch their games, using a unique game ID/disc name will allow you to have custom cover and disc art show up in OPL. Please try to communicate if you do this to make sure nobody else uses the same ID - I used SLUS_999.01 through 05 for my personal custom discs when I went through and added them, and discovered that some of the Brazilian scene had also used the same numbers, and art for those discs had managed to make it into the archive that OPL Manager uses (which is a very nice way to acquire most if not all of the art for any games one might have). Using a unique four-letter ID is preferred, and within that you have 100000 different possibilities with five digits

[2:28 PM] LocalH: Since I had not uploaded my LH1-5 discs at that point, I didn’t really care but if I had it to do over again I’d have done "LCLH-00001" etc or "LOCL" or something like that