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很好的一个gps daemon驱动,简单实用

COPYRIGHT
=========

This software (gpsd) is Copyrighted 1997, 1998, 1999, 2000, 2001, 2002 by
Remco Treffkorn, I am releasing it under the terms and conditions of the 

	GNU GENERAL PUBLIC LICENSE Version 2, June 1991

or later. a copy of which is included in the file COPYING.

GENERAL
=======

gpsd is a userland daemon acting as a liason between a GPS or
Loran-C receiver and clients. The receiver is expected to generate
position information either as NMEA-0183 sentences or in Rockwell 
binary format.

gpsd listens on port 2947 for clients requesting position, time,
velocity or altitude information.  gpsd can take information from the
GPS and translate it into something easier to understand for clients.

There is a test client included. It is called "gps". It simply
connects to the daemon and displays your latitude, longitude,
altitude, speed, track, and the signal quality from visible
satellites.  When the GPS emits GSV, it will show a diagram of
satellites in their current position in the sky.

The gpsprobe program queries GPSes for their capabilities and generates
a gnuplot recipe for an error scattergram to standard outout.

There is a project site for gpsd at <http://www.berlios/gpsd/>.
Look there for updates, news, and project mailing lists.  See that
website for a list of GPS units known to be compatible.

See the file INSTALL for installation instructions and some tips on
how to troubleshoot your installation.

CREDITS
=======

Remco Treffkorn designed and originated the code.

Carsten Tschach's gpstrans-0.31b code was the original model for nmea_parse.c.

Bob Lorenzini <[e-mail]> provided testing and feedback.

Brook Milligan <[e-mail]> combined gpsd and gpsclient
into one package and autoconfiscated it.

Derrick J. Brashear <[e-mail]> (KB3EGH) added code for the
EarthMate DeLame. He also added "incredibly gross code to output
NMEA sentences" (his own words :-) He also did the first cut at
DGPS support (see http://www.wsrcc.com/wolfgang/gps/dgps-ip.html), 
for the Earthmate.

Curt Mills <[e-mail]> (WE7U) furthered the dgps support,
writing the portion for other GPS receivers.

Eric S. Raymond drastically rewrote this code to clean it up and extend it.
His new features include:
   * Documentation (what a concept!)
   * Cleaned up, simplified command-line options.
   * Now understands the GLL (Geographic position - Latitude, Longitude)
     sentence from NMEA 3.0. 
   * Now parses both the NMEA 3.01 and pre-3.01 variants of the VTG sentence 
     correctly.
   * New y command supports satellite location -- it should no longer ever be 
     necessary for clients to go to raw mode unless they want to monitor and 
     log the NMEA stream itself.
   * New 'w' command toggles 'watcher' mode. In watcher mode gpsd ships
     a gpsd-style response for each incoming sentence as if the client
     had just sent all commands that asked for data contained in the sentence.
   * New 'x' command allows the client to query whether or not the GPS
     is on-line.
   * Massive refactoring -- one main loop now calls a self-contained
     driver object for each type.
   * The GPS-bashing code the daemon uses can now be directly linked as a
     library, libgpsd(3). 
   * C and Python libraries are available to encapsulate the client side of
     querying gpsd, see libgps(3).
   * Cleaned-up error reporting, we don't use syslog when running in foreground
     but send all error and status messages to the tty instead.
   * Added -n option to do batch monitoring of GPSes.
   * xgpsspeed is working again.  gps has been seriously reworked and improved.
   * RPMs which include installation of gpsd to start up at boot time 
     are available.
   * New gpsprobe program probes the capabilities of GPSes and generates
     error scattergrams from fixes.
   * All this in fewer lines of C than the 1.10 version.