[Patch] Sound Blaster AWE32 RAM selection

[grommit2007]

I have created a patch which allows the selection of RAM sizes of 4MB, 16MB and 32MB on the Sound Blaster AWE32 sound card.

Contrary to official Creative documentation, the EMU8000 can handle these RAM amounts.

The patch is attached below.

[JosepMa]

You definitely cannot use more than 28MB by means of the AWE32 API, because the addresses that would permit addressing those 4 remaining megabytes address the internal ROM memory.

About 4MB and 16MB, that's more about hardware accuracy.
You had to use two 30pin SIMM modules ( https://en.wikipedia.org/wiki/SIMM ), and they had to be of the same size.
And since they only had the sizes: "256 KB, 1 MB, 4 MB, 16 MB", that means you could only have 512KB, 2MB, 8MB or 32MB (limited to 28MB as I've explained above) on the AWE32.

So, what do you really want this patch for?

[grommit2007]

You definitely cannot use more than 28MB by means of the AWE32 API, because the addresses that would permit addressing those 4 remaining megabytes address the internal ROM memory.

About 4MB and 16MB, that's more about hardware accuracy.
You had to use two 30pin SIMM modules ( https://en.wikipedia.org/wiki/SIMM ), and they had to be of the same size.
And since they only had the sizes: "256 KB, 1 MB, 4 MB, 16 MB", that means you could only have 512KB, 2MB, 8MB or 32MB (limited to 28MB as I've explained above) on the AWE32.

So, what do you really want this patch for?

If the EMU8000 was unable to handle the RAM amounts I mentioned (4MB and 16MB), the AWE64 Gold, which came with 4MB RAM, would be unable to be produced with that RAM amount (I am aware that on real cards the 32MB RAM is clipped to 28MB because of the ROM address space).

Also, I found out that the ZMD chip on these cards is actually RAM for holding the effects processor code (It usually is a ZMD chip but on later cards, it's from NPN, Alliance or Hyundai, this RAM is separate from the SoundFont RAM).

[SarahWalker]

The EMU8000 may be able to handle those amounts, but you can't fit them to an AWE32. And PCem is specifically emulating an AWE32, not an AWE64 or some generic EMU8000 card.

[JosepMa]

RE: AWE64: The AWE64 didn't use 30 pin SIMM, but some Creative-specific memory modules.

Also, the AWE64 drivers are not really compatible with this AWE32 emulation (concretely, the 1MB ROM bank that this emulation supports).
I tried it on an emulated win98 and I had to recover the sbk from an old copy, because the one distributed with the AWE64 maps it differently (possibly because the ROM is different)

[leilei]

Weird. I've always used the AWE64 disc to install control/applications with my real AWE32 and never noticed anything out of the usual on the emulated one...

[JosepMa]

Not sure what really happened, and probably I did something stupid.

I had an emulated win98 where I had the creative drivers and software for AWE32, and then installed the ones for an AWE64 Value.
Somehow, midi started to not play correctly and I saw that another sf2 worked fine, but using the rom based ones (like synthgm.sbk) did not.

In the end I was able to convert it to sf2 and that restored the correct sound.

(correct sound as in playing .mid files with creative midi player)