I would strongly suspect that the gps unit that you are using output
"all" of the NMEA strings. The "tracker" serial read routine is most
probably not sufficiently robust to get through all of the jibberish and
extract only the sentences needed w/o it taking time.
Have this same problem with gps software and garmin, raytheon and
magellen NMEA output.
Using Satloc SLX receiver where only GGA,VTG,ZDA, GLL are turned on the
lag time @4800 baud is about a 1/4 mile @ 60mph and ZERO delay @ 9600
baud.
The problem w/Geographic Tracker is that it is free but.... The source
code is there and most probably could be revised to be more robust.
Someone needs the motivation to do so.
Regards
Roy Chiappini
Blackfoot, Idaho
Thomas Colley wrote:
>
> I have started using the "Geographic Tracker" tool written by Blue Marble
> for using GPS in conjunction with MapInfo V5.0. I am using this to plot
> points in car-based recording of weed sites. I am experiencing a 40 second
> lag between the digital generation of coordinate data by the GPS, and the
> availability of this data for plotting points in the MapInfo application.
> The motion of the "Current Position" indicator in the Map Window is always
> 40 seconds behind the actual current position. Line plotting indicates that
> the current position data is being read by the application, but is simply
> not being made available for point plotting for 40 seconds. Instantaneous
> plotting (+/- 3 seconds) of the current position is crucial to my operation.
> Has anyone experienced a similar problem? Is there a fix?
>
> Cheers
> Tom Colley
> Environmental GIS Analyst
> Blue Mountains City Council
> Tel: (02) 4780 5433
> Email: [EMAIL PROTECTED]
>
> _______________________________________________________________________
> List hosting provided by Directions Magazine | www.directionsmag.com |
> To unsubscribe, send e-mail to [EMAIL PROTECTED] and
> put "unsubscribe MapInfo-L" in the message body.
_______________________________________________________________________
List hosting provided by Directions Magazine | www.directionsmag.com |
To unsubscribe, send e-mail to [EMAIL PROTECTED] and
put "unsubscribe MapInfo-L" in the message body.
