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From: "Hays, Arthur (NIH/NEI) [E]" <art@lsr.nei.nih.gov>
To: "xenomai@xenomai.org" <xenomai@xenomai.org>
Cc: "Hays, Arthur (NIH/NEI) [E]" <art@lsr.nei.nih.gov>
Subject: [Xenomai] Porting from QNX?
Date: Mon, 16 Feb 2015 16:18:04 +0000	[thread overview]
Message-ID: <7E7E1F635323E543B04E7D69A4E262E7159C6AC4@msgb08.nih.gov> (raw)

Our application for laboratory automation and experimental control (for neurophysiology labs) runs on QNX on commodity x86 motherboards (when we can find 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 involve updating the display and network communication to other machines.  The jitter for this routine is not crucial.

QNX has discontinued self-hosting on x86- they are embedded only now.  Photon/PhAB is no longer supported.  So we are looking to port to another environment 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, but 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








             reply	other threads:[~2015-02-16 16:18 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-02-16 16:18 Hays, Arthur (NIH/NEI) [E] [this message]
2015-02-16 17:03 ` [Xenomai] Porting from QNX? Jan Kiszka
2015-02-16 17:25 ` Philippe Gerum

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