Download The Goonies II MMC5 Patch ROM Hack

The Goonies II (USA) Mapper Conversion
From UNROM to MMC5 (from UNROM to Mapper 5)
by Dracula X

RELEASE DATE: August 17, 2019
Last Modified: 5-21-2020

Bankswitch:
To use it, all you have to do is select a bank and jump to it.

LDA bank_number
JSR $FFE0

You can also use Nflate from http://www.romhacking.net/ Utilities to expand the ROM up to 512kb.

You can now use free RAM space at $5c00 to 5fff and $6000 to $7fff for cool or new stuff.

Bankswitching:
to bankswitch from $8000 - $Bfff and from $C000 - $ffff, here's how to do it:

LDA bank_number
JSR $FFC0
JMP New Location

or

LDA bank_number
JSR $FFC0
RTS

New location would be $8000 or $A000 etc... Bank 08 would be at $20010.

Credits:
Rockman: for info on how to convert the mapper!
Disch: for his mapper docs!

Have fun!

This patch also works for:
Goonies 2 - Fratelli Saigo no Chousen (Japan)

This patch does not work for:
Europe Version

Hacks supported:
All!

Hacks not supported:
MMC3 Hacks

Use Delta Patcher to patch the xdelta file to the ROM. 
Ignore the checksum and then patch the file.

Changes for this version 1.2:
Changed the MMC5 Setup and changed the bankswitch code to a new location
and now, all hacks are now supported except for MMC3 hacks.

Changes for this version 1.1:
Change all $FF's to $00's in the expanded ROM area from location $20000

Non Supported Emulators:
Nintendulator
RockNES
VirtuaNES