Moonsound "Emu" mode

Prophet (2494)

26-05-2023, 22:14

Like other people, I recently regain insterest in my good old Moonsound cartridge just because of the new NOP's Sale Discontinued game.

So I expanded my Moosound to 512KB (not without trouble), and at that occasion, I discovered an "EMU" jumper (J1) on the board. I googled about that but found nothing.

Does anybody knows what's the use of this jumper ? Would it allow Music Module . FM PAC compatibility or something ?

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Van Grauw

Ascended (10820)

26-05-2023, 22:24

I’m guessing it puts the FM I/O to C0H (MSX-AUDIO ports) instead of C4H? OPL4 is backwards compatible to OPL, however the MSX-AUDIO (Music Module) also has an ADPCM sample channel which is not compatible. Additionally, if MSX-AUDIO software attempts to use the ADPCM it will hang on the sample loading step, so due to this it’s not extremely useful. But might still be fun to play around with. You can also use it to use two OPL4s at the same time.

Van Louthrax

Prophet (2494)

26-05-2023, 22:46

Thanks Grauw, that sounds like a very likely explanation.

I still really enjoy the sound quality of the Moosound (in demo and music disks), and now I'm wondering if we could enjoy it in existing Music Module games. Gorby's Pipeline first comes in mind to me, it can be played on Music Module with some tweaks (I remember I added an option if SofaRun for that), and the sound is really different from the FM-PAC version (and it does not use samples ADPCM IIRC).

Do you think there would be a real difference in the sound quality between Moonsound / Music Module ? I'll give it a try anyway (and maybe add an external switch on J1 if that's the case).

Van Grauw

Ascended (10820)

26-05-2023, 22:46

For the Compile games with MSX-AUDIO support I think you need to use FRS’s MSX-AUDIO BIOS 1.3 to make that work. But I don’t think that can simply be loaded into a MegaFlashROM or something, it has kind of a unique mapper which has both ROM and RAM banks iirc.

Louthrax wrote:

Do you think there would be a real difference in the sound quality between Moonsound / Music Module ? I'll give it a try anyway (and maybe add an external jumper on J1 if that's the case).

With VGMPlay you can play MSX-AUDIO VGMs on MoonSound, though without samples.

Van Louthrax

Prophet (2494)

26-05-2023, 22:55

There's also something like a simple POKE to do before lanching the Compile games in order to "force" MSX-AUDIO (don't remember that exactly but it should be somewhere in SofaRun sources...), which kind of fakes the presence of the MSX-AUDIO BIOS.

On that subject, I'm wondering if there's a list of Compile games supporting MSX-AUDIO. IIRC, Aleste 2 does not (at least with the magic POKE I mentionned above).

Thanks for suggesting VGMPlay to make my tests, I won't have to open my Moonsound once again !

Van Louthrax

Prophet (2494)

26-05-2023, 23:11

Here's the magic thing to force MusicModule as MSX-Audio for Compile games:

ForceMModuleAsMSXAudio:
	ld	a,0x23
	ld	(0xFFCA),a
	ld	a,1
	ld	(0xFB20),a
	ret

Van JohnHassink

Ambassador (5684)

27-05-2023, 00:35

Louthrax wrote:

From BASIC, you can boot those (Compile disk-) games using:

POKE -54,35 : POKE &HF346,1 : _SYSTEM

Louthrax wrote:

On that subject, I'm wondering if there's a list of Compile games supporting MSX-AUDIO. IIRC, Aleste 2 does not (at least with the magic POKE I mentionned above).

It works with at least Golvellius 2, Gorby's Pipeline, Rune Master II and most of the DiscStations.
Pretty sure about also Puyo Puyo and maybe Aleste, but I did not check.

Van ToriHino

Paladin (925)

27-05-2023, 00:44

And with RoboPlay you can use the MoonSound to replay a lot of of MSX AUDIO and/or FM-PAC songs (including the ADPCM samples).

Van gdx

Enlighted (6429)

27-05-2023, 01:21

Nowadays it should be possible to make a moonsound with a full "emu mode", is not?

Van sdsnatcher73

Enlighted (4289)

27-05-2023, 14:16

DalSoRi2 has MSX-Audio BIOS functionality. But I don’t think it supports ADPCM…