GPS Fix

[marcel]

Hi,

I am looking for a way to check if the GPS is fixed.

Sub GPS1_NMEA (timestamp As Long, Sentence As String)
  If Sentence.StartsWith("$GPGSA") Then 
     If Sentence.CharAt(9)=3 Then
     gpsFix=True
   Else
     gpsFix=False
   End If
  End If
End Sub

I tried this using the NMEA syntax. But this seems not working all the time...

Is this incorrect or are their better ways to do this?

 

[derez]

How about this:

Sub GPS_LocationChanged (Location1 As Location)
If Location1.AccuracyValid Then  GPSFix = true else GPSFix = false

 

[Erel]

It will be simpler to handle the LocationChanged event. If it was raised then there was a fixed location.

 

[marcel]

It will be simpler to handle the LocationChanged event. If it was raised then there was a fixed location.

Ok. Thanks!

 

[Dario126]

LocationChanged method is easier, nut what about when device have GPS fix and loose it (like in tunnel)? Then LocationChanged event is not raised? How do I know that there is no more GPS signal?

Implementing some timeout variable since last fix might be some solution, but not like it too much. What if I have GPS setup not to fire up on interval, but on distance since last move then LocationChanged event will not be trigered while user is in same place. He could be there for days, but it thus not mean that there is no signal ..

 

[Erel]

You can handle the GpsStatus event it fires in short intervals. You can find the current status based on the number of satellites and status of satellites.

 

[Dario126]

To optimize my code execution I had only GPS events when GPS position moved for 100 m. So I should add another GPS object with some fixed time interval to get access for regular check of status inside locationchanged event? Will this be additional battery consumer (significant)?

 

[Erel]

Will this be additional battery consumer (significant)?

No. It is the GPS hardware itself that consumes the battery, not the listeners.