From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <4A6829D6.9060301@domain.hid> Date: Thu, 23 Jul 2009 11:13:58 +0200 From: Wolfgang Grandegger MIME-Version: 1.0 References: In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Subject: Re: [Xenomai-help] State of implementation of CAN, CANOpen in Xenomai List-Id: Help regarding installation and common use of Xenomai List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: =?ISO-8859-1?Q?Berruer_S=E9bastien?= Cc: xenomai@xenomai.org Berruer S=E9bastien wrote: > Hello, >=20 > I'm reviewing the feasibility of a project that would require the drivi= ng of > devices with real time constrains. OK, then RT-Socket-CAN is a good choice. > I'm asking for the current state of the CAN implementation. Is it a > partial or a > complete implementation of the CAN standard? What are the guarantee > about real > time latency? What exactly do you mean with CAN standard? RT-Socket-CAN allows low-level access the CAN controller to send and receive messages, handle errors and set the bit-timing. Standard, extended and RTR frames are supported. > I explored briefly the sources of Xenomai, and I read the file > "ksrc/drivers/can/README". Is it up-to-date? Is there really only > support for > the controllers listed in it? Mainly yes, what CAN controller would you like to use? Writing a RT-Socket-CAN driver is usually not a big deal. > I've read in "RTDM and applications" that there would be an effort for > implementing a CANOpen profile. But, the implementation of CANOpen > protocol is > let to users? I can't find any newer reference for that in sources or i= n the > documentation of Xenomai. What is the state of this project? If you are looking for a free CANopen implementation, CANfestival might be an option, which also supports RT-Socket-CAN, IIRC. Check http://canfestival.org/ for further information. > I've seen that there is currently only one implementation of a RT drive= r > for the > 16550A serial controller. Has anybody implemented it for other chip? What chip/hardware do you have in mind? > If I finally decide to choose a RT-Patch, instead of Xenomai, I will > have the > CAN implementation that will use the Linux networking stack. But I will > not have > any guarantee about its real time implementation, isn't it? The Linux network stack is not hard real-time capable and the real-time preemption patch will only help partially. Wolfgang.