[comp.sys.amiga.tech] D/A Sound Question

dnelson@ibiza.cs.miami.edu (Dru Nelson) (08/13/89)

 Simply, what method does the Paula chip use to compine sound channels
 0 and 1?  Does it just add and divide by 2 to average the two channels?  

 Also, how did they fit those D/A converters into one chip?  Most D/A 
 converter chips are quite large, and yes, the Paula is quite big too.
 Still, do the leave some of the process to be finished by some external
 circuitry?


%%%%%%%%%%%%%%% Internet:  dnelson@ibiza.cs.miami.edu  %%%%%%%%%%%%%%%%%%%%%%%%
% Dru Nelson  %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% Miami, FL   % os9, C, Progressive music (burrow owls to dial-a-cliche), chAos
%%%%%%%%%%%%%%% and frying my mind & spirit? on certain questions about life  %

grr@cbmvax.UUCP (George Robbins) (08/13/89)

In article <630@umigw.MIAMI.EDU> dnelson@ibiza.cs.miami.edu (Dru Nelson) writes:
> 
>  Simply, what method does the Paula chip use to compine sound channels
>  0 and 1?  Does it just add and divide by 2 to average the two channels?  

It is done pretty much analog style, by tieing the outputs of two D/A
sections to the same pin.

>  Also, how did they fit those D/A converters into one chip?  Most D/A 
>  converter chips are quite large, and yes, the Paula is quite big too.
>  Still, do the leave some of the process to be finished by some external
>  circuitry?

Limiting the resolution to 8-bits makes things relatively easy.  Each added
bit doubles you problems...  The only external processing is a current->
voltage conversion and filtering.

-- 
George Robbins - now working for,	uucp: {uunet|pyramid|rutgers}!cbmvax!grr
but no way officially representing	arpa: cbmvax!grr@uunet.uu.net
Commodore, Engineering Department	fone: 215-431-9255 (only by moonlite)