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unixronin: Galen the technomage, from Babylon 5: Crusade (Default)
Unixronin

December 2012

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Tuesday, September 6th, 2011 06:49 pm

A while back, Microsoft dumped a whole lot of outdated DeLorme mapping packages via Amazon for something like $15 each.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  The MAPS go out of date.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