Randie Ohtsji [4555] wrote:

> Does anyone know how to do trig functions with a PIC16C84 micro.  I am mainly
> after how to do ARCTAN & TAN.

Well for starters you can look at either my PIC sine:

http://www.interstice.com/~sdattalo/technical/software/pic/picsine.html

or Eric Smith's

http://www.brouhaha.com/~eric/pic/sine.html

This get's you sine and cosine. It can also provide you with tangent or
cotangent if you can afford the division.

I've been meaning to write some code for the arctangent, but-well you
know-
it's that damn time thing. But not to completely disappoint you, I can
refer
you to the October 1995 issue of Embedded Systems Programming magazine.
Jack Crenshaw (who's a very good writer btw) wrote an article and some
code
in that issue describing several ways to compute the arctangent.

Just for the heck of it, I did quick search in the back issues at:
http://www.embedded.com/mag.shtml
There's a lot of stuff there, but unfortunately they don't have
Crenshaw's
October '95 article.

Scott