[LinuxPPS] Kernel configuration and more ......

[James Boddington]

Udo van den Heuvel wrote:
> Udo van den Heuvel wrote:
>> Paul wrote:
>>> this. I then tried to use NTP (with the ATOM clock). No events were
>>> seen. So then I did cat /dev/ttyS0& (and left the process in the
>>> background) and then NTP saw the events and the PPS started to be used
>>> (but see below). Why? Why doesn't NTP open the port itself?
>> ATOM not opening a port and thus not seeing events by itself (I use ATOM
>> together with NMEA) is a problem I guess.
> 
> So I commented out my NMEA driver in ntp.conf and restarted ntpd.
> No PPS was seen for the duration of the test. (long enough for kernel
> sync and thus ATOM / PPS to be locked to external timestamps)
> 
> Can anyone confirm these findings?

You need to open the serial port before you get the pps. When testing I was 
using cat /dev/ttyS0.

-- 
    James