On March 19, 2015 7:22:03 PM CDT, Chris Johns <chr...@rtems.org> wrote: >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.
20 Hz is a 50 millisecond period. I have assumed that he meant this was the largest clock tick time quantum which is reasonable to configure. Why is that? >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 >_______________________________________________ >devel mailing list >devel@rtems.org >http://lists.rtems.org/mailman/listinfo/devel --joel _______________________________________________ devel mailing list devel@rtems.org http://lists.rtems.org/mailman/listinfo/devel
