For hardware engineer types re: sound controlers and/or codec chips ??

[William Case]

Hi;

I am chasing down the creation or production of sound on my computer.
Everything is fitting into place after being at it, on and off, for a
couple of years.  However, there is one hardware answer I don't seem
able to chase down.

Where is the sound data kept immediately on arrival at the sound card?

Whether analog or digital; whatever the source; sound arrives at the
sound card or at on-board chip(s).  Whether the sound is in 'chunks',
'segments' or 'packets',  the sound data has to be stored somewhere on
the sound card, before being coded or decoded, or before being moved to
the DMA.

I expect that the memory requirements are small, perhaps only a few
bytes, but none-the-less, the sound card has to (I would think) store
the data somewhere before processing it and putting it in a DMA buffer.

Is my assumption about temporary, perhaps 1-2 ticks, storage accurate?

Where is this data stored?

Does the sound card itself have some small capacity for memory?  
-- SRAM or DRAM?

If so, is this storage a property or function of the sound controller or
the codec chip?

Is there a way to tell the size or nature of this memory from the
specifications, or, the hardware definitions in lshw, or,
cat /proc/asound/card*/pcm*/info?

Is, for some reason, this information propitiatory to manufacturers ?

If it is propitiatory, can you give me a best guess?

In the end, this is not a terribly important issue, other than without
an explanation, the understanding of the logic chain for hardware and
software used by sound is broken.


-- 
Regards Bill
Fedora 11, Gnome 2.26.3
Evo.2.26.3, Emacs 23.1.1