[ntp:questions] Driver Help?

Karl Denninger karl at denninger.net
Tue Jun 12 21:55:17 UTC 2007

I'm hacking a copy of the NMEA driver to work with the CDMA modems 
(which provide a clock signal even if not subscribed - kinda 
interesting) and have it talking to the device.

But - even though the dispersion looks reasonable and so does jitter, 
the application refuses to consider it "synced".

I have the following.....

ntpdc> sysi
system peer:          CDMA(0)
system peer mode:     client
leap indicator:       11
stratum:              16
precision:            -19
root distance:        0.00000 s
root dispersion:      0.00165 s
reference ID:         []
reference time:       00000000.00000000  Thu, Feb  7 2036  0:28:16.000
system flags:         auth monitor ntp kernel stats
jitter:               0.001129 s
stability:            0.000 ppm
broadcastdelay:       0.003998 s
authdelay:            0.000000 s
ntpdc> peer
     remote           local      st poll reach  delay   offset    disp
*CDMA(0)        0   16  377 0.00000  0.241065 0.00697

Obviously, I'm missing SOMETHING....... the dispersion looks reasonable, 
but it will not lock up on the clock.  Any idea where I start?

Oh, the other thing I've run into is that the START routine is never 
called if I don't run the application with debugging turned on (!); no 
errors logged, just no startup.  I stuck a syslog in the "start" routine 
right at the front - it never gets executed if the ntpd app is in the 

This might be a nice driver to contribute.... if I can get the dang 
thing working! :-)

Karl Denninger (karl at denninger.net)

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