From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Hays, Arthur (NIH/NEI) [E]" Date: Mon, 16 Feb 2015 16:18:04 +0000 Message-ID: <7E7E1F635323E543B04E7D69A4E262E7159C6AC4@msgb08.nih.gov> Content-Language: en-US Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Subject: [Xenomai] Porting from QNX? List-Id: Discussions about the Xenomai project List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: "xenomai@xenomai.org" Cc: "Hays, Arthur (NIH/NEI) [E]" Our application for laboratory automation and experimental control (for neu= rophysiology labs) runs on QNX on commodity x86 motherboards (when we can f= ind ones that don't have the SMM issue). We do this because our users are = on tight grant money at universities. With QNX we measure typical 4usec and worst case maximum 6usec latency from= #INTA asserted on the PCI bus to entry of a service routine in user space.= This is when disk i/o, display updating, network activity all present. We also execute another routine scheduled by a timer every 1msec that may i= nvolve updating the display and network communication to other machines. T= he jitter for this routine is not crucial. QNX has discontinued self-hosting on x86- they are embedded only now. Phot= on/PhAB is no longer supported. So we are looking to port to another envir= onment that is self-hosted on x86 perhaps using Qt instead of Photon. >>From what I've read on Xenomai the typical latency to entry of a routine in= user space initiated by a hardware IRQ would stay the same as with QNX, bu= t the maximum would be on the order of 20-40usec on x86? Would the routine that is scheduled every 1msec be able to update displays = and use TCP/IP? Any advice would be appreciated. Thanks, Art Hays National Institutes of Health National Eye Institute Bethesda, MD 20892