From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <43A7B687.2030807@domain.hid> Date: Tue, 20 Dec 2005 08:45:11 +0100 From: Jan Kiszka MIME-Version: 1.0 Subject: Re: [Xenomai-help] Interrupt Shied (II) References: <38197.128.93.15.41.1135063005.squirrel@domain.hid> In-Reply-To: <38197.128.93.15.41.1135063005.squirrel@domain.hid> Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="------------enigB26C1F00D2088F602463E268" List-Id: Help regarding installation and common use of Xenomai List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: smannori Cc: xenomai-help , wjasper@domain.hid This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --------------enigB26C1F00D2088F602463E268 Content-Type: text/plain; charset=ISO-8859-15 Content-Transfer-Encoding: 7bit smannori wrote: > ... > Now the problems: > > 1) If I push the sample rate above 50 S/s the progam starts, but, after a > while, the real time square wave disappear. Also the "SquareWave" task > disappear from /proc/xenomai/sched. Any segfaults? Take a look at /proc/xenomai/faults (if I remember this entry name correctly now). > > 2) it is not a problem of interaction with the NON realtime square wave > because the same behavior remain if I remove the code > > 3) I tried the same program on the PPC achitecture using a PowerBook with > similar results. > > Where is the catch ? I missed something around the interrupt shield ? > > I need to develop real-time application using USB devices because we need > something usable with a laptop. Unfortunately USB is NOT supported for real > time applications and I'm not competent enough to write my real time USB > driver. > My hope is that the interrupt shield of Xenomai will save my day :) > It may improve the number of deadline misses, but it will not make them disappear. The standard Linux stack may do things in your back while you do some data acquisition, and you cannot control this. Moreover, you can suffer from low buffers when trying to issue some request to the stack, and this is also something you cannot influence as the buffers are taken from global pools. I'm hopefull that we (well, it's going to be outsourced: a student) will be able to revise the existing USB4RT stack (=>RTDM port), derive or define an interface for high-layer drivers like your USB DAQ requires, and then someone could port things over... :) Actually, USB becomes more and more important for hard-RT. One just have to think of all those 2USB devices (replace with RS232, CAN, etc.) for boxes with otherwise limited extensibility. Jan --------------enigB26C1F00D2088F602463E268 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.2 (GNU/Linux) Comment: Using GnuPG with Thunderbird - http://enigmail.mozdev.org iD8DBQFDp7aHncNeS9Q0k+IRAuGtAKCxrc3cnP+JmhOZFdbCPD/qng4vkgCgsuZY wzdQw0JvDk+vjf6oh5/70yU= =OJcA -----END PGP SIGNATURE----- --------------enigB26C1F00D2088F602463E268--