Hi Andreas,
        I'm not sure this will meet your accuracy requirements, but
it does demonstrate one solution for doing waypoint calculations
(note the limitations indicated on the descriptive page). Goetz
Romahn used a table for arctan calculations. This was done for the
Sold out Aisin-Seiki GPS-Receiver (The "US$20 GPS").

Source code url
http://www.users.bigpond.com/tobbe/disp20.zip


Descriptive page for the program
http://www.users.bigpond.com/tobbe/dl7aot.htm

Regards,
Heinz

At 7:21 PM +0200 6/12/01, Andreas Eriksson wrote:
>Hi, I'm working on a GPS project and to begin with I need to get the angle
>from two given points.
>Since I'm more familiar with CISC-type of CPUs/MCUs I'm having a bit of
>trouble doing the divisions, what I need to do is to take an arctan value
>from a result of division between the two points. Since the position is
>given in a 8-digit decimal type I wont deal with the whole number, instead
>I take the two first digits who differs and let the accuracy increase as
>nearer i get to the target.
>So, what I need is some thoughts about how I should deal with the numbers
>to get my wanted result and if my method is working, the one about taking
>the first to digits that differs in dest/source position and treat them as
>the real positions and doing the arctan on them.
>
>...or if anyone has done this kind of GPS-project before and is willing to
>let out his(/her :-) ) source...
>
>Regards
>
>Andreas
>
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