[LAU] MusE RtcTimer cannot set freq

Tim E. Real termtech at rogers.com
Thu Nov 1 22:23:12 UTC 2012


On November 1, 2012 12:28:43 PM Ralf Mardorf wrote:
> Changing file permissions didn't solve it.
> 
> Trying RTC timer...
> RtcTimer::setTimerFreq(): cannot set freq 1024 on /dev/rtc: Permission
> denied precise timer not available, check file permissions and allowed
> RTC freq (/sys/class/rtc/rtc0/max_user_freq) Trying ALSA timer...
> AlsaTimer::initTimer(): best available ALSA timer: system timer
> got timer = 72
> 
> Muse 2.0.1 Ubuntu Quantal amd64
> 
> Any hints are welcome!
> 
> Regards,
> Ralf

Greetings, Ralf, list.

In MusE, the RTC timer is for the ALSA support.
It is similar to the selection of timers found in Rosegarden or QTractor, 
 except we try to select the timer automatically.

If using only Jack Midi devices in MusE, you need not worry too much
 about RTC.

Some things in MusE are really old.
Several years ago the RTC support in Linux was just that -
 it operated on the actual RTC on the PC, and was limited in frequency
 and only one user at a time.
Yet, for MusE it was often the best choice for a timer.
But since the advent of HPET, the RTC now operates on the HPET timers
 instead, and the frequency can be set much higher now, and more than 
 one user. If I understand all of this stuff correctly.

One of our devs is trying to run MusE on BSD, where there are no ALSA
 timers, so we recently revived talking about the RTC and I think Robert
 added some better warning messages and info there.

Follow the advice given there, and here, to get the RTC up to spec.

I believe there is an RTC/HPET library now. 
We should probably try to use it instead of this awkward /sys tree stuff, eh?

Try MusE. It's kind of old-school midi, I understand you have used 
 midi for a long time, I think you might like it.
Quite literally, it improves by the hour!
The next release is, in my opinion as one of the main devs, going
 to be one of its finest ever, where everything kinda comes together
 and works as it should have long ago. Many improvements!

Cheers.
Tim.


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