From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <4E0D7DE7.50803@domain.hid> Date: Fri, 01 Jul 2011 09:57:27 +0200 From: Gilles Chanteperdrix MIME-Version: 1.0 References: <201106301212.47433.carlosnov@domain.hid> In-Reply-To: <201106301212.47433.carlosnov@domain.hid> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Subject: Re: [Xenomai-help] Writing a new driver, shoud use message pipes or shared memory? List-Id: Help regarding installation and common use of Xenomai List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Carlos Eduardo de Brito Novaes Cc: xenomai@xenomai.org On 06/30/2011 05:12 PM, Carlos Eduardo de Brito Novaes wrote: > Hello all! > Hope this question fits to the scope of the list. > > I got a PCI acquisition board and wish to write a xenomai driver for it. I had > did this before with an old ISA board and used memory heaps to exchange data > from kernel (configuration and mainly acquisition routines) and the real time > processing task. > > Now, I would like to know if I can use only message pipes for this kind of > application. I would like to use it so the entire proccess became more "unix > like", using memory heaps I think that the internals of the driver are exposed > and the any misfuncion can arise due to bad data passed from programmers. Is > this right? > > Can message pipes provide hard real time timings, about 1K/10K samples per > second and about 100 bytes on each sample? Hi, you probably should use the RTDM skin to write a driver. So, use the "read" call to get data, or if there is a big volume, use some mmaped aread, using rtdm_mmap_to_user. Regards. -- Gilles.