[ntp:questions] Timing issue with Linux and kernel PPS?
Uwe Klein
uwe at klein-habertwedt.de
Sat Nov 17 21:57:47 UTC 2012
David Taylor wrote:
> I'm seeing behaviour on rebooting a Raspberry Pi Linux system which is
> stopping the PPS signal getting through to NTP. It seems that the GPS
> device does not emit any pulses on the PPS line for some time after it
> has been powered up. This I understand and it's the time taken for a
> good enough lock to be acquired.
>
> However, it seems that if the PPS part of the kernel hasn't seen a
> transition, it does not create the pps device at least until the first
> transition is seen. The delay seems to be some 133 seconds here:
>
> Does this seem possible, and how might it be fixed?
helps?:
http://www.raspberrypi.org/phpBB3/viewtopic.php?f=41&t=1970&start=150
uwe
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