I may be reading way to much into the question. But the goal discipline the local oscillator as an alternate to GPS or WWVB etc Further assumption get the same types of services out of the oscillator Frequency and time plus pulses.
That said if its one ntp source you look at, potentially far down stream with many network hops, doesn't that make your reference only as good as that ntp server as it jitters around? Would it be better to track say 3 servers hopefully up toward the top of the ntp service. Analyze their behavior to each other to attempt to account for network behaviors and the server behaviors. Essentially compare all three and derive a number to adjust the local oscillator. I might add that by adding any 1 pps source from radio or GPS while available would really let you understand what jitter and path delays you are getting and then establish the adjustment. (Fully understand that the path is variable in IP. Love simple but I suspect, its much tougher then that otherwise why mess with GPS at all. ;-) Its that darn radio stuff. Regards Paul WB8TSL On Fri, Jul 22, 2011 at 10:25 PM, Chris Albertson <albertson.ch...@gmail.com > wrote: > Yes but in this case it really is easy; Below is an outline (don't > try to compile it.). It has a slight problem because just using > "sleep" is kind of simplistic. One should wait on the new second and > add some error chacking Point here is just to show that this is not > weeks and weeks worth of work". The below pulse a bit every second > and if the system is running NTP then the length of a second is > controlled by NTP. > > Main() > { > int status; > int fd; > int pw = 1000 /* pulse width in uS */ > fd=open("dev/tty",O_RDWR); > while(1) { > status = 1; > ioctl(fd, TIOCMSET, &status); > ussleep(pw); > status = 0; > ioctl(fd, TIOCMSET, &status); > ussleep(1000000-pw); > } > } > > On Fri, Jul 22, 2011 at 6:08 PM, Jim Lux <jim...@earthlink.net> wrote: > > On 7/22/11 3:46 PM, brent evers wrote: > >> > >> "After that all you need to do is write some code to..." > >> > >> Oh - if I had a nickel for every time I've heard that! > >> > >> Brent > >> > > > > When I worked in the physical effects business, we'd get a set of > > storyboards from a director, and we'd have to figure out how we were > going > > to build a rig or arrange the effect as required. The catch phrase was > > always "then, all you gotta do is"... > > > > representing some sort of incredibly difficult, tedious, or impractical > > activity. Sure, install 10,000 lightbulb sockets into a frame and wire > them > > up before tomorrow morning's call time at 6AM.. *all you gotta do* is get > 50 > > people to each wire 200 sockets, screw in the bulbs and test them. > > > > _______________________________________________ > > time-nuts mailing list -- time-nuts@febo.com > > To unsubscribe, go to > > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > and follow the instructions there. > > > > > > -- > > Chris Albertson > Redondo Beach, California > > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.