Sonic the Hedgehog CD (prototype 510)

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(Redirected from SCHG:Sonic CD 510 Beta)
SCHG: Sonic CD 510 Beta
Main Article
File Locations
File Locations
Art Editing
Compressed Art
*.MMD Editing
*.MMD Breakdown
Object Layout
Level Layout
General Tweaking
General Tweaking

This is the Sonic Community Hacking Guide for Sonic the Hedgehog CD (prototype 510). Sonic CD, as with all Mega-CD games, uses a filesystem with files for each code event instead of a monolithic rom. Splash screens, menus, and levels all reside in their own .mmd file with optional .bin files for SubCPU execution.

As each MMD runs separately of others (except for those which load to RAM), various pieces of code and data are repeated throughout like MMD files. This makes art editing without a disassembly very long and tedious. However, upon the release of a disassembly of Sonic CD 510, all common art and code will be consolidated so changes are reflected in every MMD including that data.

The level MMDs have the filename format RXYZ__.MMD:

  • X is the zone. R1 is zone 1.
  • Y is the act. R12 is zone 1, act 2.
  • Z is the time period. There are 4 letters that can be put here; A, B, C, or D. A is the present period. B is the past period. C is the bad future period. D is the good future period. So R12D__.MMD would contain act 2 of zone 1, in the good future period.


Sonic Community Hacking Guide
SonED2 Manual | Subroutine Equivalency List
Sonic the Hedgehog (16-bit) | Sonic the Hedgehog (8-bit) | Sonic CD (prototype 510) | Sonic CD | Sonic CD (PC) | Sonic CD (2011) | Sonic 2 (Simon Wai prototype) | Sonic 2 (16-bit) | Sonic 2 (Master System) | Sonic 3 | Sonic 3 & Knuckles | Chaotix | Sonic Jam | Sonic Jam 6 | Sonic Adventure | Sonic Adventure DX: Director's Cut | Sonic Adventure DX: PC | Sonic Adventure (2010) | Sonic Adventure 2 | Sonic Adventure 2: Battle | Sonic Adventure 2 (PC) | Sonic Heroes | Sonic Riders | Sonic the Hedgehog (2006) | Sonic & Sega All-Stars Racing | Sonic Unleashed (Xbox 360/PS3) | Sonic Colours | Sonic Generations | Sonic Forces
Technical information
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Legacy Guides
The Nemesis Hacking Guides The Esrael Hacking Guides
ROM: Sonic 1 | Sonic 2 | Sonic 2 Beta | Sonic 3

Savestate: Sonic 1 | Sonic 2 Beta/Final | Sonic 3

Sonic 1 (English / Portuguese) | Sonic 2 Beta (English / Portuguese) | Sonic 2 and Knuckles (English / Portuguese)
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