[LinuxPPS] RE: with Atom driver problems

[Rodolfo Giometti]

On Wed, Aug 30, 2006 at 12:31:10PM +0100, Tom Playford wrote:
>
> NTP is still giving a reach of 0.
> ntpq> peer
>     remote           refid      st t when poll reach   delay   offset  
>     jitter
> ==========================================================
> PPS(0)          .PPS.            0 l    -   64    0    0.000    0.000   
> 0.001

I doubt this is due LinuxPPS...

> So, NTP is connecting to the PPS inteface, and sending 'FETCH'
> commands but it's not doing anyting with it. Correct? Any ideas?

NTPD send the FETCH command to read PPS data. Stop. :)

> dmesg dump:
> 
> [...]
> drivers/pps/kapi.c: capture assert seq #292 for source 0
> drivers/serial/8250.c: serial8250: PPS assert event at 420817

Here the capture event from the GPS and saved by LinuxPPS.

> drivers/pps/kapi.c: capture clear seq #292 for source 0
> drivers/serial/8250.c: serial8250: PPS clear event at 420942

Here the clear event from the GPS and saved by LinuxPPS.

Also 420942-420817=125 is ok since your duty cycle is 50% and linux's
clock is at 250 ticks per second.

> drivers/pps/pps.c: New message from PID 5205 (flags 0)
> drivers/pps/pps.c: PPS_FETCH: source 0

Here userland application with PID 5205 is reading PPS data from
LinuxPPS.

As you can see the NTP daemon is reading the PPS events.

Ciao,

Rodolfo

-- 

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