Can I use different skins simultaneously?

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Summary of answers from Gilles and Jan (excerpt from Mailing List) :

  • Basically yes, but there are some things you have to pay attention to with Xenomai versions earlier than 2.4:

The main problem is the timer mode, different skins use. Some skins (like the posix and the native skin) are mostly used with an aperiodic timer (which grants a higher timer resolution), but some other skins (like the vxworks skin) have to be used in periodic mode.
So, if you want to use a skin which needs periodic mode, you have to activate the periodic mode in the kernel configuration (CONFIG_XENO_OPT_TIMING_PERIOD ), which in turn forces the other skins (which are normaly used in aperiodic mode) also into periodic mode (reducing their timer resolution).

  • vxworks combined with native and/or posix skin :

Is possible, but the two skins would share the same timer, and since this timer has to be in periodic mode for the vxworks skin, you would have to run the posix skin in periodic mode too. This should work, but of course you would not get the same timer resolution as the one you get in aperiodic mode.

  • native combined with posix skin

No problem, aside of the fact that both must share the same mode, either aperiodic or periodic with the same tick frequency.

The upcoming Xenomai 2.4 solves all the above issues, allowing multiple time bases to exist concurrently, regardless of their respective tick frequency.

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