Anybody have a working Garmin iQue (or know how to convert hexadecimals into coordinates)?

I need a real mathlete with an interest in geography, a GPS buff with some
math skills, or a Garmin iQue owner for this one.

My iQue has died. The only backup to some valuable waypoints I have are in
signed hexadecimal format residing in my Palm Desktop application, and I'd
love to get these into my new GPS.

Since I'm not a mathlete, can someone help get me the equivalents of the
following in a more usable numeric format? Details about the specific Garmin
format are available at http://forum.brighthand.com/showthread.php?t=9812

Here are the coordinates I need translated:
GARMIN 1E8071CA C96C24BD This one is in Seneca Falls, NY, general vicinity
of 42°54'31?N 76°47'53?W
GARMIN 1D371A10 CB86BFD2 This one is in Hawthorne, NY, general vicinity of
41°6'13?N 73°47'45?W
GARMIN 1D36A33A CB861E44 "
GARMIN 1BFA47F0 CB0AF370 This one is in Atlantic City, NJ, general vicinity
of 39°22'39?N 74°27'04?W

Running these through an online hexadecimal converter give me results that
make no sense--to me anyway--in relation to the general coordinates--
http://www.statman.info/conversions/hexadecimal.html

Maybe I'm using the incorrect converter?

I have other less important waypoints I can translate myself if someone
wants to walk me through the steps, either as pure math or through the
appropriate online converter.

As an alternative, if an iQue owner could put each one of these into the
Custom 4 field of an address book entry and send back the corresponding
coordinates from the GPS application, that would work too.

Thanks for any help you can provide!

Sent: Fri, 25 Apr 2008 16:39:22 -0500





Hi Eric,

I Think I can help you. I explain the calculation below and, using
Excel, have calculated the co-ordinates you quote.





The hexadecimal values used are "signed" and the conversion you are
doing is probably "unsigned".

The number is deemed negative if the top binary bit is set when the
number is converted to 32 bit binary.

If you convert the hexadecimal number to decimal as "unsigned" then if
that decimal result is greater than 2^31 (ie 2,147,483,648) the number
is negative in 2's complement format. If it is not then the decimal
result stands as a positive decimal number.

To determine the correct number when negative, subtract 2^32 (ie
4,294,967,296) from the decimal "unsigned" result.

Garmin treat the number as a fraction of a semi-circle where 2^31 is
equivalent to 180°. So to obtain a result in degrees, the converted
decimal number needs to be divided by 2^31 and then multiplied by 180.
The decimal degrees answer can then be presented in degrees minutes and
seconds.

If the Latitude is positive it is North, if negative it is South.
If the Longitude is positive it is East, if negative it is West.



This converts to: 42°53'35.0399"N 76°44'58.9199"W


This converts to: 41°5'2.15975"N 73°47'27.7800"W


This converts to: 41°4'52.9710"N 73°47'40.2597"W


This converts to: 39°20'36.9047N 74°28'15.9411"W







I hope this helps, Eric
Regards,
Eric Charlwood

On Sun, 27 Apr 2008 10:17:24 +0100, Eric Charlwood (ngs)



I tried to do the conversion using excel (HEX2DEC) but could not see how to get
round the signed part. Did you have to check the value first and do an IF THEN?

Geo

-----
Sent: Sun, 27 Apr 2008 16:41:47 GMT







Hi Geo,

Yes I did have to check the value first. Below are the cell entries I
used for one of the examples.

Cell D8: CB0AF370

Cell D10: =HEX2DEC(D8)
Cell D12: =D11/2^31
Cell D13: =D12*180

The result in decimal degrees is in cell D13.

Hope this helps,
Regards,
Eric Charlwood

wrote:



Thanks Eric - I had the other cells ok but could not work out the D11 bit -
saved for future use :-)

Geo