From mboxrd@z Thu Jan 1 00:00:00 1970 From: Leopold Palomo Avellaneda Date: Wed, 30 Jul 2008 00:08:48 +0200 References: <200807152346.21863.leo@domain.hid> <488D9A75.1040705@domain.hid> In-Reply-To: <488D9A75.1040705@domain.hid> MIME-Version: 1.0 Content-Type: multipart/signed; boundary="nextPart4893393.oprqVJ1GK7"; protocol="application/pgp-signature"; micalg=pgp-sha1 Content-Transfer-Encoding: 7bit Message-Id: <200807300008.48525.leo@domain.hid> Subject: Re: [Xenomai-help] OT. A question about constraints in realtime List-Id: Help regarding installation and common use of Xenomai List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Gilles Chanteperdrix Cc: xenomai@xenomai.org --nextPart4893393.oprqVJ1GK7 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Content-Disposition: inline A Dilluns 28 Juliol 2008, Gilles Chanteperdrix va escriure: > Leopold Palomo Avellaneda wrote: > > The sensable people claims that their driver works with some versions of > > Linux (till fedora 4 and some suse) but I'm not be able to run it in a > > debian etch. I don't know if the distros provide a kernel with some kind > > of modifications that solve it, but I don't think so. > > > > > > Well, thanks in advance and I'm sorry for the noise. Really, the realti= me > > stuff is something not obvious... =46irst of all thanks for the answer.=20 > The first thing to do is to get statistics about the scheduling latency > of your driver. This means measuring the difference between the date > when the driver (kernel-code) wakes up the task and the date when the > task effectively runs. The bad news is that it will be hard with a > binary-only driver. If the driver has some compilable glue, then you can > hook into this glue, otherwise, you will have to resort to ugly hacks in > the kernel code. Well, I cannot (or it's too difficult to do it with a _only_ binary driver.= =20 This driver is a lib (.so) and the user use some functions of that lib.=20 > If this latency is really the problem, then before resorting to xenomai, > you have linux-only solutions, like using a real-time priority for the > task using the driver. Well, I guess that it's the latency. They have a loop that control each=20 engine, and if the driver doesn't receive any signal in some time, it=20 disconnects the engine (some rele acts) . They works well with devices with= 3=20 motors but the 6DOF model fails. I have to think how to solve it ... Regards, Leo =2D-=20 =2D- Linux User 152692 PGP: 0xF944807E Catalonia --nextPart4893393.oprqVJ1GK7 Content-Type: application/pgp-signature; name=signature.asc Content-Description: This is a digitally signed message part. -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.9 (GNU/Linux) iEYEABECAAYFAkiPlPAACgkQaC7AnPlEgH6XvgCeMgLOjRLXsYr2UmTYicJ5S/CS jlIAn0NPcbmpQ7njooXo6Z6qMO6EXT1R =AMJl -----END PGP SIGNATURE----- --nextPart4893393.oprqVJ1GK7--