From mboxrd@z Thu Jan  1 00:00:00 1970
From: Rene Herman <rene.herman@keyaccess.nl>
Subject: Re: arecord | aplay expected delay
Date: Sun, 16 Mar 2008 22:36:20 +0100
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To: van der Linden <ejvanderlinden@hetnet.nl>
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On 16-03-08 11:05, van der Linden wrote:

> I'm running arecord and aplay under uCLinux on a Blackfin DSP.
> 
> In this way I loopback my audio.
> 
> Does anyone know what delay I can expect between audio input and audio output?

Not me, but you just want to loop without doing anything to it? An analogue 
input? Every card I know can just loop it's own inputs out again. That is, 
In -> Out, while you have In -> ADC -> bus -> cpu/memory -> bus -> DAC -> Out.

> I measure at my test board 50ms. I want to have about 1ms!

You'd need a pretty fast system I suppose. Why does your card not loop 
directly itself? You can still record it as well...

Rene