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Author Topic: Mega Drive Plus Games for Mega SD - How are they made?  (Read 306 times)

Batzarro

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Mega Drive Plus Games for Mega SD - How are they made?
« on: September 19, 2019, 11:41:05 am »
Hi. Since the Mega CD flash cart came out which lets you also play Mega CD games without a Mega CD, there's been a lot of videos about it on Youtube. They sometimes mention Mega Drive Plus (or +?) games, they are rom hacks which allow you to play the game with audio from .WAV files.

For example there's a version of Out Run with the arcade soundtrack and a version of Streets of Rage 2 with the SOR Remake music floating around the internet. But they don't have a readme file saying who made them and I can't seem to find anything on Google concerning how these rom hacks are actually made. Sorry does anyone know how?

Jorpho

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Re: Mega Drive Plus Games for Mega SD - How are they made?
« Reply #1 on: September 19, 2019, 11:10:30 pm »
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FAST6191

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Re: Mega Drive Plus Games for Mega SD - How are they made?
« Reply #2 on: September 20, 2019, 06:07:20 am »
For others just learning of this then the following video will hopefully get you up to speed on the background of it all
https://www.youtube.com/watch?v=i569jGYkDiU

As for the question then sounds like any in depth hardware hack -- learn how the hardware is addressed and its protocols for speaking to it, modify the game to do that rather (or in addition to) what it already does. As this is nice 16 bit era hardware, which is to say before sound formats became somewhat standardised, with the added perk of the console in question having a straight up processor with its own memory (trivially making it Turing complete) and multiple chips it governs within that setup, then each hack is probably going to be its own ordeal with its own approach needed for the really fun aspects. However reading some of what is to come you can get 95% of the way there and help yourself out within many games to make a somewhat easier approach.

https://forums.terraonion.com/viewtopic.php?f=26&t=1027 mentions something by way of example, as does https://pastebin.com/f0AiBAG1

For a more general approach there is the dev manual I found at the bottom of https://terraonion.com/en/producto/megasd/
https://downloads.terraonion.com/public/MegaSD_DEV_Manual.pdf

EvilJagaGenius

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Re: Mega Drive Plus Games for Mega SD - How are they made?
« Reply #3 on: September 20, 2019, 08:46:47 pm »
Just learned about the flash cart from this thread and dang, that looks cool.  I have a Genesis and 32X but no CD, so this looks right up my alley... if I had the funds.  I'm hoping either the price goes down or someone tries to clone it.  In the meantime, does anyone know if emulators support these kinds of hacks?

Jorpho

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Re: Mega Drive Plus Games for Mega SD - How are they made?
« Reply #4 on: September 20, 2019, 10:46:22 pm »
In the meantime, does anyone know if emulators support these kinds of hacks?
The thread I linked to suggests Regen.
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