OSDev.org

abraker95 wrote:So how does the computer know the port addresses when I look at them using device manager?

Because the people programming computers are using technical documentation, not user manuals. If you cannot tell the difference at a glance, and all this talk about "vendor ID" and "datasheet" confuses you, then rest assured: Even with the correct documentation you wouldn't be able to use the audio ports.

I did A LOT of research and I became stuck on Direct Memory access(DMA). I've got a working example from the internet, but have no idea how it works.

That is a specific example of playing a .WAV format file under DOS, using the Soundblaster. It may be relevant to your own OS, however, since Bochs (an x86 emulator) has SB emulation. You just won't have the DOS functionalities ("conio.h" et al.) available, and the BIOS neither if you're in protected mode.

As for DMA, looking up "DMA reference" on Google (try it, it's pretty easy!) got me this interesting looking website. A search for "intel 8237", the DMA chip for ISA, got me a ton of results. I don't feel like sifting through them, but you can check it out. Looking up "SoundBlaster" got me a bunch of info too, for many cards that include SoundBlaster compatibility.