MAMEWorld Forums - News - Re: DU: Sit down before you read this...part 2

> > After 34 years, Bryan McPhail and ArcadeHacker finally did the impossible and
> figured
> > out how to correctly emulate the original Bubble System version of Gradius!
>
> Depending on your philosophy on emulation, "correctly" could be something of an
> overstatement.
>
> This doesn't at all cheapen what they've achieved, but the code in question doesn't
> emulate the bubble memory management controller, which is believed to be some sort of
> MCU. It's more of a high-level simulation of the bubble memory system rather than
> emulation itself.
>
> It's somewhat akin to various drivers where MAME had a 100% correct simulation of a
> given protection MCU: From an end user's perspective it's functionally "there", but
> there's still work to be done on the team's end to bring up the level of hardware
> documentation and accuracy.
>
> Not trolling, just pointing out a few caveats regarding this admittedly impressive
> achievement.

I think it's a good starting point tho, and gaining a better understanding of this hardware, to at least allow extraction of the correct data is better than nobody having a clue about it.

You've authored things yourself where current media access functionality is HLE that will be replaced later (cdi comes to mind) although obviously with the cdi that allowed a lot more development to occur, while here the rest of the hardware is basically already understood as Konami quickly realised bubble memory was a mistake and re-released them using ROMs on otherwise practically identical hardware.

There are plans to get the Bubble Memory MCU decapped, and the people working on it are people who have produced proven results before, so I have confidence we'll see more progress, and maybe even replacement Bubble Memory MCU controllers developed to make dumping Bubble Memory at at lower level (prior to error correction etc.) easier. I imagine there are a lot more places BM was used outside of the arcade games considering several companies had hardware supporting it.

Even in this preliminary form, this does rank for me as one of the most pleasing things to see so far this year as at the very least it means a usable copy of the data from one Bubble Memory game has been preserved, and that is one area were there is a definite time limit on it happening as it's very fragile media.