Comparing frequencies with FFT

hi,

i want use fft library on arduino uno compare incoming sound interval of [1000hz..5000hz] , have no idea how so.
i used code loop found on forum make reading of fft data easier (i had troubles monitor showing me random characters) :

code: [select]

/*
fft_adc.pde
guest openmusiclabs.com 8.18.12
example sketch testing fft library.
it takes in data on adc0 (analog0) , processes them
with fft. data sent out on serial
port @ 115.2kb.  there pure data patch for
visualizing data.
*/

#define log_out 1 // use log output function
#define fft_n 256 // set 256 point fft

#include <fft.h> // include library

void setup() {
  serial.begin(115200); // use serial port
  timsk0 = 0; // turn off timer0 lower jitter
  adcsra = 0xe5; // set adc free running mode
  admux = 0x40; // use adc0
  didr0 = 0x01; // turn off digital input adc0
}

void loop() {
  while(1) { // reduces jitter
    cli();  // udre interrupt slows way down on arduino1.0
    (int = 0 ; < 512 ; += 2) { // save 256 samples
      while(!(adcsra & 0x10)); // wait adc ready
      adcsra = 0xf5; // restart adc
      byte m = adcl; // fetch adc data
      byte j = adch;
      int k = (j << 8) | m; // form int
      k -= 0x0200; // form signed int
      k <<= 6; // form 16b signed int
      fft_input[i] = k; // put real data bins
      fft_input[i+1] = 0; // set odd bins 0
    }
    fft_window(); // window data better frequency response
    fft_reorder(); // reorder data before doing fft
    fft_run(); // process data in fft
    fft_mag_log(); // take output of fft
    sei();

      serial.println("start");
    for(int = 0;i < 128;i++) {
    serial.println(fft_log_out[i]);
    }
    delay(10000);

  }
}

what should do?

quote from: pinguu on feb 28, 2014, 04:35 pm

what should do?

please more specific.

• what trying accomplish?


• you showed code - did work way expected?


• presuming didn't work hoped- since you're posting here - did do?

and, can timer0 interrupt.  code disables on, , calls delay(), relies on timer0 interrupt in order function.  either refrain disabling interrupt, or don't call delay().

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