[pskmail] Re: A tiny progress report regarding gps
- From: Per Crusefalk <per@xxxxxxxxxxxx>
- To: pskmail@xxxxxxxxxxxxx
- Date: Sat, 10 Feb 2007 21:24:31 +0100
Hi Rein and all,
I started this "thread" by looking at gpsd as I figured that would be
the best way to interface with a gps. I then set my eyes on GPS::NMEA
and saw how easy that was to use...
The benefit of working without gpsd would be to make installs easier and
minimize external dependencies. if GPS::NMEA now uses a lot of cpu then
that is certainly not in its favour. We could do it all the hard way
also and open a port and parse nmea direct. Such as here:
http://vancouver-webpages.com/peter/nmea.perl
But, then we would really be building a new gpsd and I find thats a
waste of effort. So, should we go with gpsd then ?
On a sidenote I have a hard time adjusting to the use of loops in perl.
If I would do that in any other language then everything would freeze.
In Pascal I would call Application.ProcessMessages once in a while to
leave some time for the OS to do its things.
73 de Per, sm0rwo
lör 2007-02-10 klockan 20:53 +0100 skrev Rein Couperus:
> Hi Per,
>
> I have been testing around a bit an d found a problem with GPS::NMEA.
>
> below is a little test progam. It reads the gps constantly and puts the time
> and position into ~/mail/.utc
>
> The problem is that reading the socket this way takes up to 30% of my CPU.
> (As a reference, fldigi takes 3% of may CPU).
>
> I have also checked gpsd, and that does it with 0% CPU. I will now start some
> testing with NET::GPSD.
>
> Here is the little test program. Even if you only want the position it takes
> a lot of CPU time:
>
> #!/usr/bin/perl
> use GPS::NMEA;
> use Data::Dumper;
>
> my $gps = GPS::NMEA->new(Port => '/dev/ttyUSB0',
> Baud => 4800);
>
> print "Starting gps\n";
>
> while(1) {
> my($ns,$lat,$ew,$lon) = $gps->get_position;
>
> $data= Data::Dumper->new([$gps->{NMEADATA}],[])->Dump;
> @items = split ",", $data;
> for $utc (@items) {
> if ($utc =~ /(\d\d:\d\d:\d\d)/) {
> if ($ns eq "S") {
> $ns = "-";
> } else {
> $ns = " ";
> }
> if ($ew eq "W") {
> $ew = "-";
> } else {
> $ew = " ";
> }
> $outstring = sprintf("%s %s%s %s%s\n",
> $1,$ns,$lat,$ew,$lon);
> `echo "$outstring" > ~/mail/.utc`;
> print $outstring;
> last;
> } else {
> unlink "$ENV{HOME}/mail/.utc";
> }
> }
> select undef, undef, undef, 0.5;
> } # end while
>
> exit;
>
>
> > -----Ursprüngliche Nachricht-----
> > Von: pskmail@xxxxxxxxxxxxx
> > Gesendet: 10.02.07 15:39:04
> > An: pskmail@xxxxxxxxxxxxx
> > Betreff: [pskmail] Re: A tiny progress report regarding gps
>
>
> >
> > I agree, that is an absolute must.
> >
> > Per
> >
> > (Sunny, -10C in the sun now)
> >
> > lör 2007-02-10 klockan 13:54 +0100 skrev Rein Couperus:
> > > forgot, it would be nice if we could also get gps time so we can update
> > > the clock without internet...
> > >
> > > Rein
> > >
> > > (Sunny, 20 degrees in the shade...)
> > >
> > > > -----Ursprüngliche Nachricht-----
> > > > Von: pskmail@xxxxxxxxxxxxx
> > > > Gesendet: 10.02.07 11:58:00
> > > > An: pskmail@xxxxxxxxxxxxx
> > > > Betreff: [pskmail] Re: A tiny progress report regarding gps
> > >
> > >
> > > >
> > > > lör 2007-02-10 klockan 10:55 +0100 skrev Rein Couperus:
> > > > > Hi Per,
> > > > >
> > > > > I think what we need is something we can poll from pskmail, so we can
> > > > > get the position when we want.
> > > > > One way to do that is to fork a new process which does exactly what
> > > > > you did, and put the result in a file which we can read any time from
> > > > > any of the other preocesses...
> > > > >
> > > > > Rein EA/PA0R/P
> > > > >
> > > > Ok, that should be easy (will fix).
> > > > I haven't looked at the client at all so I'll talk to you agn when I
> > > > need to have some gui control of this. I suppose we can agree that we
> > > > wont need gpsd if we do it this way ?
> > > >
> > > > Another subject:
> > > > Dave has improved fldigi dominoex, oh7jjt and I are testing dominoex16
> > > > on 80 (and 40) meters now. Looks good so far, snr is really bad on 80
> > > > now but I got some parts anyway (more on that as snr improves).
> > > > This means I am using fldigi 1.32e and its much slower on psk than it
> > > > used to be, timing could be a bit off now.
> > > >
> > > > 73 de Per, sm0rwo
> > > >
> > > >
> > > >
> > > >
> > >
> > --
> > Pär Crusefalk
> > Turnévägen 5
> > 14243 Skogås
> > Tel: +4687717482
> > Mob: +46768800670
> >
> >
> >
> >
> >
> >
>
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