[SOLVED] how to know gps device point at which direction?

how to know gps device point at which direction?

Currently I manage to get the direction degrees using below code:

d = Math.Atan2(Math.Sin(long2 - long1) * Math.Cos(lat2), _
    Math.Cos(lat1) * Math.Sin(lat2) - Math.Sin(lat1) * Math.Cos(lat2) * Math.Cos(long2 - long1))

Dim direction As Double = (RadToDeg(d) + 360.0) Mod 360

which, in my case let say I got 250.65°

I assign each of the direction values from 0 to 360 to its particular image from imageList which loaded in the pictureBox. (currently I have 36 compass images with different arrow direction, each represent 10 degrees)

When my device is pointed to the north, the arrow image is showing the correct direction, but when when I rotate the device (pointed to anywhere which is not north), the arrow image doesn't change, means it is not showing the correct direction anymore.

So my question is, is it possible to know in which direction the gps device is pointed?

Edit: I'm using Honeywell Dolphin 6000 Scanphone device

Solution

The Honeywell Dolphin 6000 documentation doesn't mention a magnetometer or compass, so you're probably SOL. But, if it does have one, then you should be able to find methods to access it in the SDK

I recommend downloading and reviewing any APIs and documents that come with the SDK and look for references to the magnetometer or compass. Microsoft does not have standard APIs to access those sensors in Windows Mobile, so you will need the SDK from Honeywell to get that information.