[ntp:questions] clockvar output from PPS

David J Taylor david-taylor at blueyonder.co.uk.invalid
Tue Feb 21 16:39:02 UTC 2012


"unruh" <unruh at invalid.ca> wrote in message 
news:mBP0r.1156$py5.659 at newsfe09.iad...
[]
> ??? the format of pps0 output is nothing like the format of the output 
> of
> the serial port as far as I know.
> If you are going to use pps, you have to set up your serial port to run
> interrupts and to report those interrupts. On linux, you have to load
> the modules pps_core and pps_ldisc and then link the serial port dcd
> line to the pps_ldisc using ldattach 18. That creates a pps0 device in
> /dev and in /sys/class/pps/pps0/. I suspect similar things are needed in
> bsd.
>
> Ie, It is NOT sufficient to simply wire up the sure board, plug it in
> and run the atom driver. You also have to tell you system to timestamp
> and report its serial line interrupts.

As far as I know, no such steps are needed in FreeBSD 5.4, 8.0 or 8.2.  No 
need to load any extra modules, just to create a link or two.  I did 
compile the kernel PPS support, though.

Cheers,
David 



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