8087-Based Fast Fourier Transform (FFT)
This assembly language subroutine uses an 8087 to compute a Fast Fourier Transform. It is callable from a 'C' program as a subroutine.
Efficient computation of numerically-intensive operations often requires recourse to system hardware resources at the lowest level afforded by assembly language. This routine directly accesses an 8087 math coprocessor in computing the Fast Fourier Transform on an array of complex floating point input values.
Fully documented source code is provided for the FFT routine. Instructions for assembling and linking to a suitable high level calling program (written in Microsoft C) are also provided. Some general hints on simple tests for any FFT routine are also described.