Error of heading variable (&H580) VB6

[Alejandro Lobo-Guerrero C]

Another question

I program with vb6, I need to obtain the heading of the aircraft, I am using the variable 580 but I have an error as for the grades.

This is the way like I obtain the data and process, I show in a Label.

Dim dwresult As Long

Dim Heading As Long

If FSUIPC_Read(&H580, 4, VarPtr(Heading), dwresult) Then

If FSUIPC_Process(dwresult) Then

HeadingProces = Heading * 360# / (65536# * 65536#)

If Sgn(HeadingProces) > 0 Then

Label1.Caption = "RUMBO: " & Round(Val(HeadingProces))

ElseIf Sgn(HeadingProces) < 0 Then

Label1.Caption = "RUMBO: " & Round(Val(360 - Abs(HeadingProces)))

End If

Else

Label1.Caption = "Processing: " & ResultText(dwresult)

End If

Else

Label1.Caption = "Reading: " & ResultText(dwresult)

End If

A thousand thanks for all. :wink:

[Pete Dowson]

I program with vb6, I need to obtain the heading of the aircraft, I am using the variable 580 but I have an error as for the grades.

What error? Sorry, I don't understand what you are asking.

Regards

Pete

[Alejandro Lobo-Guerrero C]

Pete

The error is that the variable gives me information that doesn't correspond to the current direction of the airplane, if in the simulator the airplane has heading 200, in the program the variable 580 send me a heading of 240 until with more differs among the FS and the variable obtained through FSUIPC. :?

Thanks,

:wink:

[Pete Dowson]

The error is that the variable gives me information that doesn't correspond to the current direction of the airplane, if in the simulator the airplane has heading 200, in the program the variable 580 send me a heading of 240 until with more differs among the FS and the variable obtained through FSUIPC. :?

Are you comparing TRUE direction with MAGNETIC direction by any chance? Please take the Magnetic Variation into account.

If you still think it is wrong, show more figures for comparison so I can see, but also state where you are in the world. In some places the MagVar is small, other places it is very large. Even in Seattle, for example, it is about 20 degrees.

Even better, please try using FSInterrogate, part of the SDK and deliberately provided for exactly this sort of assistance. view the heading there AND the magnetic variation in offset 02A0.

There's also a lot of logging and monitoring facilities in FSUIPC for you to use, to find out what you are doing wrong. Please take a look at those.

Regards

Pete

[jd]

do it the math this way

x / 65536 / 65536 * 360

[Pete Dowson]

do it the math this way

x / 65536 / 65536 * 360

Why's that, John?

Guess I'll never understand VB! ;-)

Pete