Profile

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

December 2012

S M T W T F S
      1
2345678
9101112131415
16171819202122
23242526272829
3031     

Most Popular Tags

Expand Cut Tags

No cut tags
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A while back, Microsoft dumped a whole lot of outdated DeLorme mapping packages via Amazon for something like $15 each.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  The MAPS go out of date.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.

Reply

From:
Anonymous( )Anonymous This account has disabled anonymous posting.
OpenID( )OpenID You can comment on this post while signed in with an account from many other sites, once you have confirmed your email address. Sign in using OpenID.
User
Account name:
Password:
If you don't have an account you can create one now.
Subject:
HTML doesn't work in the subject.

Message:

If you are unable to use this captcha for any reason, please contact us by email at support@dreamwidth.org


 
Notice: This account is set to log the IP addresses of people who comment anonymously.
Links will be displayed as unclickable URLs to help prevent spam.