Minimum RTEMS system clock frequency

[Chris Johns]

On 19/03/2015 8:06 pm, Alexander Krutwig wrote:
>
> currently I am working on the implementation of FreeBSD timecounters
> into RTEMS as illustrated in Ticket #2271 of the developer's board
> (https://devel.rtems.org/ticket/2271).

This is really cool stuff and I think the graphs so far are excellent.

> In the progress, I found out that the minimum RTEMS system clock
> frequency should at least be 20Hz to guarantee a correct functionality.
> Are there users that are troubled by this minimum system clock frequency?

I am a little confused with the wording here.

To me a 'system clock frequency' is the CPU clock or core clock or 
something similar. Is this a frequency of the tick interrupt for RTEMS ?

If this is a tick frequency do you mean this is the maximum frequency ? 
A period of 50usecs is too short for any system I know of so I can only 
assume this is a maximum frequency and minimum period.

If this is a maximum frequency that seems ok with me. This is a system 
timer and my experience is any high speed timing should use dedicated 
timers tailored to the task, or example IEEE 1588 (PTP).

Chris