NAME

GPS::gpsd - Provides a perl interface to the gpsd daemon.

SYNOPSIS

 use GPS::gpsd;
 $gps=new GPS::gpsd();
 my $point=$gps->get();
 print $point->lat, " ", $point->lon, "\n";

or

 use GPS::gpsd;
 $gps=new GPS::gpsd();
 $gps->subscribe();

DESCRIPTION

GPS::gpsd provides a perl interface to gpsd daemon. gpsd is an open source gps deamon from http://gpsd.berlios.de/.

For example the method get() returns a hash reference like

 {S=>[?|0|1|2],
  P=>[lat,lon]}

Fortunately, there are various methods that hide this hash from the user.

METHODS

new

Returns a new gps object.

subscribe(\&sub)

Subscribes subroutine to call when a valid fix is obtained. When the GPS receiver has a good fix this subroutine will be called every second. The return (in v0.5 must be a ref) from this sub will be sent back as the first argument to the subroutine on the next call.

get

Returns a current point object regardless if there is a fix or not. Application should test if $point->fix is true.

getsatellitelist

Returns a list of satellite objects. (maps to gpsd Y command)

port

Get or set the current gpsd TCP port.

host

Get or set the current gpsd host.

time(p1, p2)

Returns the time difference between two points in seconds.

distance(p1, p2)

Returns the distance difference between two points in meters. (plainer calculation)

track(p1, time)

Returns a point object at the predicted location of p1 in time seconds. (plainer calculation based on speed and heading)

baud

Returns the baud rate of the connect GPS receiver. (maps to gpsd B command first data element)

rate

Returns the sampling rate of the GPS receiver. (maps to gpsd C command first data element)

device

Returns the GPS device name. (maps to gpsd F command first data element)

identification (aka id)

Returns a text string identifying the GPS. (maps to gpsd I command first data element)

protocol

Returns the gpsd protocol revision number. (maps to gpsd L command first data element)

daemon

Returns the gpsd daemon version. (maps to gpsd L command second data element)

commands

Returns a string of accepted request letters. (maps to gpsd L command third data element)

GETTING STARTED

KNOWN LIMITATIONS

BUGS

No known bugs.

EXAMPLES

 #!/usr/bin/perl
 use strict;
 use lib './';
 use GPS::gpsd;

 my $gps=GPS::gpsd->new();
 my $data=$gps->get();
 my %fix=('?'=>"Error", 0=>"No Fix", 1=>"Fix", 2=>"DGPS-Corrected Fix");
 print "gpsd.pm Version:", $gps->VERSION, "\n";
 print "gpsd Version:", $data->{'L'}->[1], "\n";
 print "Fix:", $data->{'S'}->[0], "=", $fix{$data->{'S'}->[0]}, "\n";
 print "Lat:", $data->{'P'}->[0], " Lon:", $data->{'P'}->[1], "\n";
 print "Host:", $gps->host, " Port:", $gps->port, "\n";

 $gps->subscribe(handler=>\&gps_handler);

 sub gps_handler {
   my $point=shift();
   print join " ", "Fix", $point->{'S'}->[0], $point->{'P'}->[0], $point->{'P'}->[1], "\n";
   return $point
 }

AUTHOR

Michael R. Davis, qw/gpsd michaelrdavis com/

SEE ALSO

gpsd http tracker http://twiki.davisnetworks.com/bin/view/Main/GpsApplications

gpsd home http://gpsd.berlios.de/