[ntp:questions] NMEA ref.clock better than my ISP's timeserver?

Hal Murray hal-usenet at ip-64-139-1-69.sjc.megapath.net
Sun Jun 28 01:16:19 UTC 2009


>I'm not sure whether the NMEA driver attempts to send anything /to/ the 
>GPS device.  If not, three lines might to (ground, TX from GPS, PPS), 
>otherwise four lines are required.  If you want to take USB power from the 
>server (as I now do), it's five lines minimum.

The driver expects the data to arrive without any help.  That
works with all the NMEA devices I've worked with.  You set them
up ahead of time by sending them a sequence of commands which
differ from device to device.

The driver does send "$PMOTG,RMC,0000*1D\r\n" every poll interval,
with a comment about some Motorola device needing it.  (That's one
per poll interval rather than one per second.  I don't expect it
to work very well.)

-- 
These are my opinions, not necessarily my employer's.  I hate spam.




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