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Lose the per-driver PPS code

Dave wants to lose the per-driver PPS code and let the ATOM driver handle it all.

Let's use this topic to discuss issues about this set of bugs.

WhatSorted ascending Status
arbiter (seems OK)
as2201 (seems OK)
hpgps (seems OK)
jupiter bug_small.png Bug #560
Master bug_small.png Bug #557
msfees bug_small.png Bug #561
mx4200 bug_small.png Bug #562
nmea bug_small.png Bug #563
oncore bug_small.png Bug #559
parse bug_small.png Bug #558
ripencc bug_small.png Bug #564
trak bug_small.png Bug #565
true bug_small.png Bug #566
zyfer bug_small.png Bug #567


Harlan: Do the remarks "seems OK" mean - OK as they do not use any of the PPSAPI?

-- FrankKardel - 01 Feb 2006


Yes, it means that I did a grep PPS refclock*.c and the ones marked "seems OK" only discussed PPS in their comments.

-- HarlanStenn - 01 Feb 2006



The thing is that the refclock drivers know exactly whether the PPS of the device they are controlling is valid by the information from the device itself.

ATOM/PPS must use PPS derived time stamps only when the clock is doing well. ATOM/PPS has currently no way whatsoever to know about the health state of PPS (I currently see a 500ppm frequency check) - it assumes that PPS is always valid when it is there.

We have seen refclock/network scenarios where knowing whether PPS is healthy was absolutely crucial (effect: oscillating clock setting of several 100ms).

The scenario was invalid PPS information from a PPS source and valid time time information from the network.

For ATOM/PPS we would need an interface where the PPS health information is available to ATOM/PPS.

Currently this task is managed in the refclock drivers (some better, some worse).

-- FrankKardel - 01 Feb 2006



This topic: Dev > WebHome > LoseThePerDriverPPSCode
Topic revision: r5 - 2006-02-01 - 13:38:05 - SteveKostecke
 
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