Hello, Yes - the application cycle (as far as I can tell) should be synchronized to the return of rt_timer_read().
I've tried two methods: (1) a regular Xenomai task using rt_task_wait_period() (after setup with rt_task_set_periodic()), and (2) a Xenomai task awoken on an interrupt/timeout using rt_intr_wait() where the timeout period is calculated using rt_timer_read() on entry/exit from rt_intr_wait(). The period of the real-time task is set for 250 micro-seconds. Xenomai task latency is on average in the 1 to 4 micro-second range, sometimes seeing a datapoint in the 10 to 20 micro-second range. Best regards, --George Broz Moog, Inc. Industrial Group -----<[email protected]> wrote: ----- To: <[email protected]> From: Florian Pose Sent by: Date: 02/08/2012 12:40AM Subject: Re: [etherlab-users] failing dc-sync-check (and rtdm patch) Am 30.01.2012 21:33, schrieb George Broz: > In Xenomai, I call rt_timer_read() which should return > nanoseconds since 1970. (The configuration for Xenomai has > CONFIG_XENO_OPT_TIMING_PERIODIC=n aka "tickless mode"). This > is supplied to _application_time(). master_sync_reference() > is called immediately after, and ecrt_domain_queue() > and ecrt_master_send() very soon after that. Does your application cycle run synchronized to the time source returned by rt_timer_read(), i. e. how is your wakeup time programmed? -- Viele Grüße, Florian Pose ------------------------------------------------------------------------ Dipl.-Ing. (FH) Florian Pose [email protected] Tel.: +49 201 / 36014-13 Ingenieurgemeinschaft IgH Gesellschaft für Ingenieurleistungen mbH Heinz-Bäcker-Str. 34 D-45356 Essen Amtsgericht Essen HRB 11500 USt-Id.-Nr.: DE 174 626 722 Geschäftsführung: - Dr.-Ing. S. Rotthäuser, - Dr.-Ing. T. Finke, - Dr.-Ing. W. Hagemeister Tel.: +49 201 / 360-14-0 http://www.igh-essen.com GnuPG key: CCA047CC 2007-12-18 [expires: 2012-12-16] Fingerprint: 0081 4005 FE9F 73FF 4BDA A409 0011 4E20 CCA0 47CC ------------------------------------------------------------------------ _______________________________________________ etherlab-users mailing list [email protected] http://lists.etherlab.org/mailman/listinfo/etherlab-users _______________________________________________ etherlab-users mailing list [email protected] http://lists.etherlab.org/mailman/listinfo/etherlab-users
