RE: comedi_command and RTLinux

The problem I'm having is executing the comedi_command_test function
from within a real-time thread.  Have you done this?  I was using sample
code taken from the cmd.c and was playing with slipping it in the
RTLinux frank example.

Anyway, it looks like I can set up the command and even call it from my
kernel module as long as I don't test or call the command from RT
priority.  I.E. I seem to only be able to call the comedi_command_test
and comedi_command from the init_module routine.  So, how do I set
things up to let the DAQ card do its work at its rate and let the RT
thread do its job at its (slower) rate?  For example: my DAQ card can
collect data at some fast rate (200KHz) but the best rate my RTLinux box
can do is say 20KHz.  So the 20KHz RT task would read the array of
results collected by the card at the faster rate.   Is this a valid
design?

-Evan


-----Original Message-----
From: John Sims [mailto:john_at_coherentimaging.com] 
Sent: Friday, November 22, 2002 2:12 PM
To: Evan Carey
Subject: Re: comedi_command and RTLinux

On Fri, 2002-11-22 at 13:06, Evan Carey wrote:
> Does anyone have an example of using the comedi_command and
> comedi_command_test from a RTLinux real-time thread that they would
mind
> sharing?  I'm having no luck with it.  When I attempt
> comedi_command_test from a rt thread my machine just locks up.  Is
this
> possible?  A bad idea? Or what?
> 
> I thought I saw someone ask this once before in this group but I never
> saw a reply to it.
> 
> Thanks,
> Evan
> 
I have some stuff I'm doing with comedi and RTAI, if that would work. 
What kind of problems are you having?
-- 
John Sims
VP Operations
Coherent Imaging, Inc
7348 S Alton Way
Suite H
Englewood, CO 80112
303.768.9005 - Office
303.768.0009 - Fax

Received on 2002-11-23Z00:11:26