Startup and Init

Startup and Init

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flowchart TD
  dos["DOS/Exec hunk load"] --> load["Load .dat + .32 assets"]
  load --> a4["A4 workspace<br/>data_base + 0x7FFE"]
  a4 --> loop["Main loop LAB_1280"]
  loop --> vp["Viewport refresh 0x5382"]
  vp --> v3d["3D view 0x2ECE"]

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Entry

• Real executable path starts at 0x08 (BRA.W) and lands at 0x18.
• Primary jump at 0x20: JMP $248AE.
• 0x26+ contains embedded strings (Version 1.01, MM2Boot:, MM2Play:), not code.

Init Core (0x248AE region)

1. Early output helpers print characters/newlines via the 24E1C chain.
2. 0x24920: LEA $7FFE, A4 sets the global runtime base.
3. Clears MANX arena around A4-$5E62.
4. Loads Exec base from $4.W into A6.
5. Opens dos.library via JSR -$198(A6) (OpenLibrary).
6. Runs allocation/setup routine (0x24928):
   • Calls LAB_2567C (AllocMem wrapper)
   • Writes MANX signature
   • Builds process/runtime structures
7. Final engine binds:
   • JSR -$7FF8(A4) (engine thunk/table bind)
   • JSR -$7B48(A4) (game boot)

Important Strings

• 0x24914: dos.library
• Early static data includes world/class/race labels used by UI.

Notes

• This init is hybrid: DOS/Exec setup plus custom engine bootstrap.
• It does not map cleanly to a single main() call/return flow.

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See also

Page	Why
Runtime Memory Map	A4 workspace
Main Loop and Map	Scheduler