Hi,
I am running the FFT library on the 28069 FPU. I have linked the "rts2800_fpu32_fast_supplement.lib" which improves the performance of the FFT magnitude. However, I am measuring the amount of time it takes my 28069 experimenters kit to perform the following functions from the FPU library and it takes approximately 3x longer than expected. I am running at 90Mhz CPU.
My RFFT_SIZE is 256. I load all data in RAM memory (not flash).
As you can see the RFFT_adc_f32u takes roughly 240usec to complete. This is approx 240e-6 * 90e6 = 21,600 cycles.
Likewise the RFFT_f32_mag takes 200 usec or approx 18,000 cycles.
From the FPU-SW-LIB-UG-V1.40.00.00 I should expect the following benchmarks:
For RFFT_adc_f32u:
And
So it takes approximately 3x more cycles than expected to process these functions. Any ideas on what I'm doing wrong? BTW- I previously ran these functions on the 28377D and got much faster resutls.
Thanks,
Rick