[ntp:questions] GPX18x LVC 3.50 firmware - high serial delay problem workround

unruh unruh at wormhole.physics.ubc.ca
Sat Jan 15 18:53:16 UTC 2011


On 2011-01-15, David J Taylor <david-taylor at blueyonder.co.uk.invalid> wrote:
> "unruh" <unruh at wormhole.physics.ubc.ca> wrote in message 
> news:slrnij1g6n.mnc.unruh at wormhole.physics.ubc.ca...
> []
>> ??? There is a program which takes the PPS signal and takes the nmea
>> sentence and tells ntpd how much out the computer clock is from the true
>> time. If you are not using gpsd, you are using some other program.
>> Insert the name of that program whereever in my message I used the word
>> gpsd.
>
> No program is actually needed - just an oscilloscope looking at the PPS 
> and serial outputs.
>
> In this particular case, there is no separate program as such, just ntpd 
> with the type 20 refclock looking at the serial signal, and a type 22 
> refclock looking at the PPS signal through a modified device drive.

So you are separating the PPS from the nmea, and wondering how to get
them together again? The best way is for the same program to look at the
PPS and the nmea so it can associate them. Your process is to deliberately
separate them and then wondering why it is hard to associate them
again.


>
> Cheers,
> David 
>




More information about the questions mailing list