dme hold

[Highvolt]

Hi,

I'm trying to write a DME-HOLD function:

in short:

I can use DME lat/long to do this (0x0880, 0x0884) but i also need the elevation (just like you get elevation data of vor1)

Pete, is it possible to find this data and give it an offset?

Edit: Offset needs to be available for FS2002...

More about dme hold:

every vor/dme beacon has 2 frequency's. By selecting a vor freq in a today's navcom, the dme receiving frequency is paired from the vor frequency, and automaticly selected by your dme equipment.

lots of IR rated aircraft have a "dme-hold" function. This function lets a pilot 'hold' a certain dme frequency, while putting another vor frequency in the navcom. This way, nav1 is tracking a vor/dme, while the dme-hold is tracking the previous vor/dme.

since there is no way in FS to enter dme frequency's, i'm trying to mimic this behaviour by taking the vordme lat/long & elevation, and the airplane's lat/long elevation. With this data, a slant range calculation is possible.

Only one problem exists, dme only beacons dont have an elevation entry in the fsuipc list :(

Regards,

Wim Van Ertvelde

[Pete Dowson]

I can use DME lat/long to do this (0x0880, 0x0884) but i also need the elevation (just like you get elevation data of vor1)

Pete, is it possible to find this data and give it an offset?

Edit: Offset needs to be available for FS2002...

Actually I already do get the altitude. Internally it does occupy the DWORD following the Longitude, both for NAV1 and NAV2. In fact the NAV2 one is accessible now, just not documented -- check offset 083C.

The only reason the NAV1 value isn't accessible is that I had no space where I mapped the other values, and really didn't think it was needed at the time. The place where it should be is 0888 but that's a location used since FS98 days for the 'active engine' flags. Shame really.

Mind you, they only use the first byte (1st nybble really), so I suppose a reasonably accurate value could be stored there as a DWORD as well. Otherwise I'll need to map it elsewhere.

Only one problem exists, dme only beacons dont have an elevation entry in the fsuipc list :(

Since in FS you don't get a DME with no VOR (else you couldn't tune it) wouldn't the DME Lat/Lon/Alt be the same as that of the associated VOR?

Regards,

Pete