[ntp:questions] best jitter on qnx always = 0.977

Chris Albertson albertson.chris at gmail.com
Tue May 10 19:12:33 UTC 2011

2011/5/10 Николай Орехов <nowhere at mail.ru>

> Well, I'm using PPS driver which measures ticks with presision more than
> one
> millisecond using ClockCycles and system interrupt.
> Even with ref clock jitter less than 1ms I got 0.977 jitter.
> I'm agree that system jitter is closely connected to presision of system
> clock. But reference clock jitter may be even lower.

If your system time jumps in units of 1ms then even a perfect ref clock
would appear to have jitter of 1ms.

Chris Albertson
Redondo Beach, California

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