From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <457559AE.5090804@domain.hid> Date: Tue, 05 Dec 2006 12:36:14 +0100 From: Jan Kiszka MIME-Version: 1.0 Subject: Re: AW: [Xenomai-help] vxworks- and posix-skin simultaneously References: <5D63919D95F87E4D9D34FF7748CE2C2A6C63C4@domain.hid> In-Reply-To: <5D63919D95F87E4D9D34FF7748CE2C2A6C63C4@domain.hid> Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="------------enig8B053540000C354038F6F7B6" Sender: jan.kiszka@domain.hid List-Id: Help regarding installation and common use of Xenomai List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Roderik_Wildenburg@domain.hid Cc: xenomai@xenomai.org This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --------------enig8B053540000C354038F6F7B6 Content-Type: text/plain; charset=ISO-8859-15 Content-Transfer-Encoding: quoted-printable Roderik_Wildenburg@domain.hid wrote: >>> Can anybody tell me about the actual state of using=20 >> vxworks-skin and posix-skin simultaneously ? Is it possible,=20 >> compiling one application with vxWorks-skin and an other one=20 >> with the posix-skin and to use/execute these two applications=20 >> simultaneously on one system ? >> >> Yes, feasible. There are example applications available for=20 >> both skins, so setting up your own quick test will not take=20 >> you much time. >> >>> In an earlier posting I have read, that all skins (or at=20 >> least the native and the posix one) should be compiled as=20 >> modules, so they do not overide the timer mode. Is this still=20 >> true ? And if yes, dosn?t need the posix skin an aperiodic=20 >> timer, but the timer is set to periodic mode by the vxworks=20 >> skin ? So, can an vxworks application and an posix=20 >> applications run together ?? >> >> It's true that the vxworks skin still forces the nucleus into=20 >> periodic timer mode. This is a known shortcoming of the=20 >> current timer subsystem. >> As announced earlier, we are aiming at a redesign to overcome=20 >> this during the 2.4 development cycle. Ideas exist, remaining=20 >> issues are also identified. But our resources are still=20 >> limited, so there is no promise on a time-frame. >> >=20 >=20 >> Anyway, if you do not rely on having sub-tick timer precision=20 >> for the posix applications you are planning, the available=20 >> support should already be fine for you. >> >=20 > Sorry, but what does "sub-tick timer precision" mean (isn?t the timer c= ounting ticks) ? I mean that you can only rely on tick resolution for both skins with the currently available timer subsystem. In the future the vxworks skin tick will be mapped on a periodic timer in an exclusively one-shot (high resolution) timer implementation. > Do I have to use the posix timers in a different way, when using period= ic mode, or is just the timer resolution changing (incremnting by 1000000= when the period is 1ms e.g.) ? The time unit of posix services remain nanoseconds, just the resolution changes. > What is a reasonable value for the timer period in the kenrel settings = (1ms=3D1000000 ns ?) Depends on available CPU resources on the target (check the load under 2.3-rc2 via /proc/xenomai/stat) and the required minimal resolution (often defined by the fastest periodic job). Jan --------------enig8B053540000C354038F6F7B6 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.5 (MingW32) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iD8DBQFFdVmvniDOoMHTA+kRAuM7AJ0SsZcC3TkwKAnE/yA7j9b3jNNgEwCcCSYV /JWlbhlmgypuKVVWWT3UJBc= =CYRt -----END PGP SIGNATURE----- --------------enig8B053540000C354038F6F7B6--