Hi,
let me describe again what I did.
I had an deterministic source for a signal (an fm sweep)
repping away every .4 seconds or so.
I plugged this source into the #1 input of my midiman delta1010,
and
after
installing the OSS drivers,
running ossxmixer and setting the source for OUT#1 to IN#1,
I observed the In#1 and out#1 of the delta1010 on my scope.
This was done with an unpatched mandrake 8.1 linux box ( kernel-2.4.8 ),
and a 400Mhz Pentium.
the I/O latency (respective delay between in and out) as observed on
the scope was about 1.4 msecs, which corresponds ~ 64 samples at with
fs=48Khz.
As I review this mailing list I've come to understand that I should expect
latencies O(10's of milliseconds) with an unpatched kernel.
Instead I'm seeing a rock solid 1.4msec.
If these latencies are a fact of life, then the only way I can explain
this is that the ossxmixer program is setting up a register (software)
enabled hardware loopback mode where the ADC's output are fed directly
to input of the DACs. Most codecs have this feature as a first
bootstrap capability to test the wiring of a new circuit.
How else do I explain my observation ?
Thanks,
Ira
Ekhaus [EMAIL PROTECTED]
http://www.synapcorp.com
Synap Corporation phone:781 641 3295
71 Glenburn Rd fax :781 623 5533
Arlington, MA 02476
