I too am working on a FFT application, also for the analog devices microconverter.

My first pass, compiling the c code (using Kiel c-51) from 'numerical recipies', yielded a program >8k flash memory available.

I have not been able to locate the intel app note AR-521 on the web either.

I was able to find this web link:

http://gasser.anest.ufl.edu/documents/8051/fft/

and, from some other web reference "8052 Microcomputer simplifies FFT design", Arnold Rosenberg, Electronics, May 5, 1983.

I have assembled the web link code succesfully (watch out for the incorrect dseg for the data) but have not tested or modified it for the aduc812 A/D converter (DMA).

Is there anyone else still working on this?

Randy Dawson