Subject: Re: [linux-audio-dev] Another Annoying "How Do I Get Started" Question
From: Christopher Lee (clee_AT_gnwy100.wuh.wustl.edu)
Date: Thu Jul 12 2001 - 08:39:34 EEST
>>>>> "Benno" == Benno Senoner <sbenno_AT_gardena.net> writes:
Benno> Not sure if it's enough for you, but since most pro-audio
Benno> equipement has some intrinsic latency in it, then I think it's
Benno> not worth the trouble to try to get single sample latency. In
Benno> theory it's possible but then you probably do need some special
Benno> hardware that can interrupt you once per sample (eg 44100 times
Benno> per second) possibly triggering an RTLinux module (without Linux
Benno> cannot guarantee that your routine gets called in time) that
Benno> does the actual DSP stuff. You can guess the difficulty of
Benno> achieving this from a programming effort point of view. It
Benno> would require you to write your own audio drivers, write an
Benno> rtlinux kerel module, be careful what you do with the FPU (FPU
Benno> flags need to be saved/restored while you are in kernel space)
Benno> etc etc.
I've read that the fastest x86 intel architecture can do interrupts is w/
max latencies of 40us using rtlinux. You might be able to do at least the
interrupt part with a PPC-based system (1us interrupts).
-chris
This archive was generated by hypermail 2b28 : Thu Jul 12 2001 - 08:51:26 EEST