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Author Topic: SMB1 Demo mode modification???  (Read 1871 times)

pb1592

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SMB1 Demo mode modification???
« on: April 20, 2012, 12:19:18 pm »
Hello,

I wanted to know if anyone has any experience with editing/modifying the walk/run/jump/timing patterns for Mario in the demo mode for SMB1. I'm not referring to modifying the game physics, just how long mario walks, when he jumps and runs, etc while in the demo mode waiting for the player to press start.

I have seen several hacks where this appears to be modified to correspond to new level designs but I cannot find any info on how to do this or how involved it is. Is there some sort of memory map that defines the actions/timing of mario in the attract/demo mode which could theoretically be altered with a hex editor? Any advice would be appreciated. Thanks!

-Brian



KingMike

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Re: SMB1 Demo mode modification???
« Reply #1 on: April 20, 2012, 12:57:25 pm »
SMB Disassembly
http://www.romhacking.net/documents/344/

Quote
DemoActionData:
      .db $01, $80, $02, $81, $41, $80, $01
      .db $42, $c2, $02, $80, $41, $c1, $41, $c1
      .db $01, $c1, $01, $02, $80, $00

DemoTimingData:
      .db $9b, $10, $18, $05, $2c, $20, $24
      .db $15, $5a, $10, $20, $28, $30, $20, $10
      .db $80, $20, $30, $30, $01, $ff, $00
Just search for those hex values.
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pb1592

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Re: SMB1 Demo mode modification???
« Reply #2 on: April 21, 2012, 11:36:27 am »
Thanks for the info. After looking into it even more I realized that SMB utility has has a "record intro demo" option that allows for this.  :)

frantik

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Re: SMB1 Demo mode modification???
« Reply #3 on: April 30, 2012, 03:57:32 am »
yes the demo record is the easiest way to do it.  but you only have a limited amount of moves u can record, as seen in the disassembly