2012/9/19 Tim E. Real <termtech@rogers.com>
On September 19, 2012 12:55:26 AM Tim E. Real wrote:
> Ya know, there *is* another old timer which MusE supports:
> Ye olde RTC Clock.
>
> When you start MusE (possibly with debug messages), do you
>  see any messages about the RTC clock? Permission denied?
>
> I haven't gotten the RTC clock to work for a long time but I think
>  Robert wrote some info about poking the /proc tree to make it work.
> Try the README.

Rats!
First of all there's outdated info in the README.

Where it says:

      - make sure MusE can set the rtc clock:
            echo 8192 > /proc/sys/dev/rtc/max-user-freq
            inspect with:
            cat /proc/sys/dev/rtc/max-user-freq

That should read /sys/class/rtc/rtc0/max_user_freq.
At least here on *buntu.

Can someone change it if I don't get to it?

I'll give it a shot tonight if time permits... Thing is I had done improved instructions for this on the webpage but it seems it got lost with the unfortunate rollback of the server. I forgot to put it in the README, in which case all would have been well.
 

Second, the frequency here is stuck at a paltry 64 !
When I try to poke it I get permission denied.

This is one of the things that can be reconfigured which I listed before. I believe it's another proc/sys register.


And that's with desktop OR low-latency kernels. Crud !

So MusE still fails RTC when it tries to set it to 1024,
 and so falls back to ALSA timer as usual.

+1 For a new HP timer driver.

And optional ALSA - of course, Flo!

Yeah, about that. I haven't gotten around to debate this, I thought I would just voice a slight reluctance for this.

Making ALSA optional, to remove a dependency is well and all, but I worry it means changing the internals in a way that we loose timing, both latency and jitter. 
This is mostly just a fear and it's not necessarily true, I just wish us to be aware of this risk.

I'm not sure how this is implemented in jack but running with big buffers won't that directly incur a latency penalty that we are completely immune to with the alsa sequencer support?

Regards,
Robert