Apply ROM Hacks and Patches

Make ROM patches stick to your game images.

Suppose you’ve gone to a web site such as DeJap’s SNES Bahamut Lagoon (http://www.dejap.com/bl.php) and downloaded an English-language patch to apply to the related Japanese-language ROM ( [Hack #70] ). If you examine the patch, you’ll find that it comes in the form of a mysterious .IPS file, probably zipped up. What the heck do you do to actually make this patch work? You have two options, which are shown in the following sections.

Direct IPS File Patching

The traditional approach involves creating a new file from the ROM and the IPS patch. Use a utility such as IPSWin or JIPS (both available from http://zerosoft.zophar.net/), select the patch file and the ROM to patch, and let it do its job. You can also use the DOS version of IPS (http://www.zophar.net/utilities/patchutil.html) with the simple command:

C:\Roms\> IPS.EXE EXAMPLE.SMC EXAMPLE.IPS

Either way, you’ll end up with a combined file that includes the patched data. Make sure to keep a backup of your old master ROM in case something goes horribly wrong.

You also have to make sure that the checksum is correct on the ROM you’re patching and that it hasn’t changed from the original in any way. Do this using simple DOS utilities kindly hosted by The Whirlpool, such as SMC (http://donut.parodius.com/utilities/smc.com):

C:\Roms\> SMC.COM /S EXAMPLE.SMC

If the ROM is pristine, everything should be fine.

Emulator-Based IPS Autopatching

Many popular SNES emulators ...

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