ROM hacks: Introducing the Sega Master System Hidden FM Collection



Oh I see! Don’t want my yacking, eh? Just go straight to the download then. Click: Here



Did you know that, unlike its Western Counterpart, the Japanese Sega Master System had its own FM sound chip? oh, you did? Well of course to you would – you’re a smart,witty and generally amazing retro gaming fan.

What you may not know, however, is that due to the Japanese Master System’s abrupt termination, a surprisingly large amount of Western-only Master System games retained FM soundtracks. Rather than take them out, programmers would often simply bury them inside inaccessible bits of game code.



hidden fm

Will an FM soundtrack help solve the underlying issues with Battle Out Run? (spoiler: no.)



A Good Few Years ago, SMS Power! forum User “Sonic of 8” uncovered a number of Action Replay codes that would allow these hidden soundtracks to be heard – although only in certain emulators and not on the original hardware.

As I’d already been meaning to get my feet wet with z80 programming, and no one seemed to have undertaken the task of creating the ROM patches needed to make these soundtracks work with real hardware, I thought I’d have a go at creating these patches a myself.



hidden fm

Though buggy, Dynamite Dux has one of the more impressively complete soundtracks.



To download the finished patch set please click: here

The package contains the necessary ROM patches, a multiplatform tool for patching the ROMs and a readme to walk you through it.

What’s that? you want to here the soundtracks in action? Knock yourself out. All soundtracks are recorded from a Japanese Master System:



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About Fatnick

Hello! How do you do? I'm Fatnick, a chiptune-making ZX Spectrum-loving frog from South London. When not skirmishing, you can find me over at or @Mechafatnick and listen to me on Spotify

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  1. Pingback: The Sega Master System Hidden FM Collection 2: Incomplete soundtracks – Skirmish Frogs

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