Update. I would like to add that if the input signal from arm_fft_bin_data.c (the arm_fft_bin_example) is used the ARM test passes for the 1024 point FFT (max. bin at 213)
When changing this file for the reference signal the same problem results.
This is the test signal case passed through the same code.
Output
Passing a 16kHz signal (assuming 48mHz sampling and thus 24kHz bandwidth) instead gives
Output
showing maximum frequency at 8kHz and the actual signal rather small at 16kHz (this is a256 point graph but result is identical for 1024 or whatever is used).
Therefore the ARM test passes for 1024 point and the test signal but results are very wrong for other signals ???
Regards
Mark