Hi Magician, First of all thank you for FFT Library for Arduino Due, SAM3X CPU !

I was planing to use example Arduino sketch FFT_ovSerMon_0.1d to run FFT for Signal of 500kHz.Well known for Arduino due is that ADC sampling rate is 1MSPS.

Title Arduino Due II Arduino Due

MCK- Hz 84,000,000 II 84,000,000

Prescaler 2 II 1

ADC Clock 14,000,000 II 21,000,000

ADC Clock Cycle 20 II 20

Sample Speed-Hz 700,000 II 1,050,000

Freq. Range. Max- Hz 350,000 II 525,000

Pockets 2,048 II 2,048

FFT Pockets 1,024 II 1,024

After testing, results are OK if SMP_RATE is less than 600000UL ! My goal is to measure signal up to 500kHz. And for that I need to use prescaler 1 and #define SMP_RATE 1000000UL ! Please advice what changes are required to be done in example sketch? I have tried to change :

t->TC_CMR = TC_CMR_TCCLKS_TIMER_CLOCK5 | // use TCLK5 (prescale by 1, TIMER_CLOCK5 input is equivalent to Master Clock), but no success!