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  • Very unprecise tick VxWorks Simulator

    From daniel.casini@gmail.com@21:1/5 to All on Thu Jun 16 03:43:43 2016
    Hi, I'm using VxWorks Simulator (in Workbench 3.3, VxWorks 6.9) to develop my downloadable kernel module. I have observed that the system tick is very unprecise, even without loading any custom application on the OS (only custom services, shell, etc).
    This is due to the simulator? There is any way to make the system tick more precise? I have extracted from the system viewer the time (in milliseconds) between consecutive TickAnnounce events.
    This is the result (15.7081ms, 15.6449ms, 15.4803ms, 15.6732ms, 5.5385ms, 16.5509ms, 15.7812ms, 31.2167ms, 2.1us, 31.1806ms, 1.4278ms, 20.6505ms, 15.6543ms, 15.6855ms, , 15.6987ms, 15.6174ms, 15.4918ms, 22.0923ms, 15.6773ms, 62.596ms, 1.3556ms, 20.7355ms,
    15.5821ms, 15.8103ms, 15.4216ms, 15.5977ms, 15.6658ms, 21.614ms, 15.7254ms, 15.6281ms, 15.6535ms, 15.9216ms, 15.229ms, 22.6309ms, 15.6084ms).
    Since the system tick frequency set by default in the simulator is 60hz, the correct period should be 16.667 ms.

    Can this problem be caused by the simulator? In this case, there is any way to make the simulator more precise? Thanks

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  • From eric_lp56@yahoo.fr@21:1/5 to All on Fri Jun 17 01:02:22 2016
    Yes this is caused by simulator. Simulator does not care about precision but care about staying synchronized with host clock: It is expected that it delivers exactly sysClkRate ticks per second. To get a better precision the easiest way is to modify
    default clock rate to match host tick period (50hz is usually better).

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