Steve, Undoubtedly someone else on this list will simply have the exact source code that will compile up and do the job under Hi-Tech C, but as a general matter of course, two excellent places to look for this kind of thing are: http://www.netlib.org/ and http://math.nist.gov/gams/ Also, I did a search on http://www.google.com for the words "FFT source code", and came up with 3299 hits, So I tried "FFT source code PIC" and got 241 hits. "FFT source code PIC Microchip" gave 26, although a good half of them were PICLIST posts :-) Among those last 26 posts, I found the following article which you may find interesting... http://www.edtn.com/embapps/emba035.htm --Bob On Fri, Sep 03, 1999 at 12:18:14AM +0100, Steve Thackery wrote: > Colleagues, > ... > So, it looks like I'm knackered unless I can find an FFT module that will > integrate with Hi-Tech C. It doesn't matter if it's in Hi-Tech-compatible > assembler, C source or even an object file. I just need an FFT module that > I can use in a Hi-Tech C project. > ... -- ============================================================ Bob Drzyzgula It's not a problem bob@drzyzgula.org until something bad happens ============================================================