How do I get PSG instruments? | MSX Resource Center (Pagina 4/5)

incognito ergo sum (116)

28-07-2004, 21:44

yeah, a replayer USING NSF music data (just ignoring the replayer code itself)
You can't play JUST the music data, as you don't know its format!
It would mean you would have to reverse engineer the music format of every single NSF file and code a custom player for it! It would be madness...

Van NYYRIKKI

Enlighted (5918)

28-07-2004, 23:29

I also did a replayer... It plays Amiga MOD-files trough PSG. (Just sent it to downloads database)

System requirements: MSX1, diskdrive & 64Kb RAM.

Ps. Greetings to MäSäXi , this time I didn't put too heavy system requirements, or did I? Maybe it should load from cassette

Van ro

Scribe (4698)

29-07-2004, 09:24

yeah, a replayer USING NSF music data (just ignoring the replayer code itself)
You can't play JUST the music data, as you don't know its format!
It would mean you would have to reverse engineer the music format of every single NSF file and code a custom player for it! It would be madness...

true, I found that out already. I was kinda curious though.... Too bad, oh well. GEM could be cool enough I suppose.
thanx

Van anonymous

incognito ergo sum (116)

29-07-2004, 14:09

If there is enough demand, I could turn GEM into a GBS player. Even a 3.58MHz MSX2 would be enough to play most (if not all) games' music nicely.

It would also allow me to do some extra work on the actual sound emulation, as it's not much more than routing the frequencies to the PSG currently, with most of the actual features of the gameboy sound chip not emulated.

I do know that for a game like Megaman (IMO, megaman series has great music!) you can PAUSE the game and the music will play at full speed.

So euh, guys, let me know if you're interested (same counts for a NSF player)

Van idrougge

Resident (44)

29-07-2004, 16:59

As for the NSF format, I think that it's very unfit for the MSX, considering that it's works using ripped replay routines, meaning you have to code a 6502 emulator for your poor little MSX.
Actually I did that already
I have to find time to test it and add some extra code. I could write a NSF format player, but really, isn't playing the games much more interesting?

Emulation on our poor little MSX is already being done in NYYRIKKI's KSS player, which emulates a Z80 on the MSX's Z80, similar to NSF.

The thing is, is that really for a poor little MSX? I thought that KSSPLAY was only feasible on faster systems.

Van anonymous

incognito ergo sum (116)

30-07-2004, 02:32

Well, I haven't tried NYYRIKKI's KSS player personally, but think about this:
A music player generally uses about 15% CPU time. So basically you only have to emulate the Z80 at 500 kHz (or 0.5 MHz) in order to play the music at full speed.

That makes a 3.58MHz MSX 6 times faster than the Z80 speed it needs to emulate. That should be more than enough!

Van idrougge

Resident (44)

30-07-2004, 05:40

That's true, I just hope it works that way. Still, with an alien format such as NSF, the CPU has other tasks to attend to as well, how daunting dependent on ambition.

Edit: Furthermore, the requirements for KSSPLAY state a "fast MSX", which I interpret as more than a 3,58 MHz Z80.

Van NYYRIKKI

Enlighted (5918)

30-07-2004, 09:26

Unfortunately I don't get 15% speed out of my Z80 emulator. I think 5% is more close to truth.

Practically 3.5MHz is not enough to play KSS files. With R800 you can play MoonBlaster based KSS songs etc. without problem, but for example FAC soundtracker based KSS files are very close the edge, where it starts to slow down.

Van anonymous

incognito ergo sum (116)

30-07-2004, 13:04

Oh, that's too bad... So I've been a bit too optimistic :\
Looks like you got some optimizing to do, NYYRIKKI

Van NYYRIKKI

Enlighted (5918)

30-07-2004, 13:24

Yes, I know... Next you suggest dynamic recompilation, but no... I'm not gonna do that.

It is quite a well optimized otherways... It is just that slow because of virtual memory, that KSS files need. (Ýou can not see emulator from emulated machine)
Note, that it will also swap from disk, if you don't have enough RAM :9