[nas] isolate input/output?

[Paul Fox]

hi erik -- 

erik wrote:
 > On Sun, Mar 11, 2007 at 01:33:33PM -0400, Paul Fox wrote:
 > > i'm realizing, however, that my problems may have only just
 > > begun.
 > >
 > > a) it's alsa-based, and nas is using the alsa/oss
 > > compatibility layer,
 > 
 > I've just checked that nasd (in this case for input) and alsa output to
 > the same sound hardware works for me. So not all hope is lost. :-)

good!  thanks for trying that.

 > 
 > > b) it may or may not be good about only opening the input device, and
 > 
 > This could be tested by first starting lircd and then nasd. nasd should
 > fail to open the device if lircd opens it for output as well and you
 > would notice if starting of nasd breaks lirc operation.

i'm afraid lircd blocks nasd from getting the device, forever:
    openDevice
    openDevice: current sample rate = 8012
    openDevice OUT /dev/dsp mode 2
    openDevice: waiting on output device
    openDevice: waiting on output device
    ...repeats...

 > > c) you've already implied that my
 > > hardware may be half-duplex.  so none of this may work in the end
 > > anyway.  :-)
 > 
 > IMHO you should check this first, as this is a basic requirement.

any suggestions on how to check this?  is there a way to "ask"
the system?  it's an EPIA-M mini-itx motherboard, with a "VIA
VT1616 6-Channel AC'97 Codec".  it's advertised as capable of
doing surround-sound, but i can't find anything about duplexness. 
(duplicity?  :-).

i'll spend some more time looking at the lircd code to see if i can
figure out if it's opening the output device as well.

paul
=---------------------
 paul fox, pgf at foxharp.boston.ma.us (arlington, ma, where it's 31.6 degrees)