Log in

No account? Create an account
Journal Friends Calendar Profile View Website Previous Previous Next Next
hacking is - Habemus plus vis computatoris quam Deus
Ramblings of a Unix ronin
hacking is

A while back, Microsoft dumped a whole lot of outdated DeLorme mapping packages via Amazon for something like $15 each.

Well, sure.  The MAPS go out of date.  But the included GPS receiver doesn't, and the entire principle of GPS relies on having incredibly accurate time sources.  This time source information is available both in the GPS NMEA data stream and via PPS.  Obvious application is obvious.

Well, I've been studying the issue from the Solaris 10 point of view for some time, but eventually concluded that the driver support just doesn't seem to be there.  However, it's a different story on Linux.

Short story?  Using the GPS receiver from the MS package, I now have my own local stratum 0 timeserver.  Subject to system latency (which should be low on this machine, with six 3.2GHz cores), it should be accurate to about ±1µs. With port baud rate turned up to 115200, ntpd reports zero jitter.

...Oh, the mapping software? That went in the trash.  Duh.

This entry was originally posted at http://unixronin.dreamwidth.org/822104.html. That post currently has comment count unavailable comments.
You may comment there via OpenID even if you do not have a Dreamwidth account.

Tags: ,
Current Location: Gilford, New Hampshire
Current Music: Assemblage 23 :: Storm :: Human (2004, 05:43)

Output (1) || Input
(Deleted comment)
unixronin From: unixronin Date: September 7th, 2011 12:41 am (UTC) (Link)
If I'm correctly identifying which marking is the model number (which I'm fairly sure I am), it's a Pharos X13-51914. Works fine with ntpd v4.2.6 using the XType for "Generic NMEA GPS Receiver" at

Edited at 2011-09-07 12:43 am (UTC)
Output (1) || Input