fft_led/main.c

#define F_CPU 16000000UL

#include<util/delay.h>
#include<avr/io.h>
#include"fix_fft.h"
#include"avr_adc.h"
#include"light_ws2812_AVR/Light_WS2812/ws2812_config.h"
#include"light_ws2812_AVR/Light_WS2812/light_ws2812.h"


#define STARTADC ADCSRA |= (1<<ADSC)
#define PB_mic PB0

//resolution fft calc: 
//https://3roam.com/fft-resolution-bandwidth-calculator/
//128 samples , 1kSPS  = 7.8Hz
//interested in 0-10000 Hz
// 
//128 bins a 7.8hz = 0...1000Hz
//
//we have 8 leds:
//bands 125hz/band -> 16 bins
//
//1-7.8 - ca 130hz
//2-	255hz
//3-	380
//4-	505
//5-	630
//6-	755
//7-	880
//8-	1kHz
int main (void)
{
		int i,i2;
		int colorb;
		int colora;
		int avg;
		char sample[128];
		char im[128];
		struct cRGB led_bar1[8];
		//DDRB = (1<<mic);//would be setting output, default is input so no need for setting
		setupADC();
		for(i=0;i<8;i++)
		{
				led_bar1[i].r=0;
				led_bar1[i].g=0;
				led_bar1[i].b=0;
		}


		while(1)
		{
//######RECORD SAMPLES#######
				for(i=0;i<128;i++)
				{	

						STARTADC; 
						sample[i] = (ADCH-128)*2; //read Analog value register 8bit center -128
						im[i]=0;		//pseudo data for funciton
				}
				fix_fft(sample,im,7,0);//im[i] is always zero
//####Averaging Data####
//
			   for(i2=0;i2<128;i2++)
			   {

						sample[i2] = sqrt(sample[i2] * sample[i2] + im[i2]* im[i2]);
			   }

				for(i=0;i<8;i++)
				{
						for(i2=1;i2<=16;i2++)
						{
						sample[i] = (sample[i] + sample[i*16+i2])/2;
						}
						//avg written to sample[0..7]
						//contains values scaled to int boundarys
						//scale them to 0..256
						sample[i]= map(sample[i],0,30,0,255);
						led_bar1[i].r=0;;led_bar1[i].b=0;
						//if(sample[i]<2) sample[i]=2;
						led_bar1[i].g=sample[i];
		
				}


								
				ws2812_setleds((uint8_t *)led_bar1,8);
		}

				//	_delay_ms(50);
//				for(i=0;i<8;i++)
//				{
					/*	for(colorb=0;colorb<256;colorb++)
						{
						led_bar1[i].r=10;led_bar1[i].g=colorb;led_bar1[i].b=0;
						ws2812_sendarray((uint8_t *)led_bar1,8*3);	
						_delay_ms(1);

						}
						for(colorb=256;colorb>0;colorb--)
						{
						led_bar1[i].r=0;led_bar1[i].g=colorb;led_bar1[i].b=10;
						ws2812_sendarray((uint8_t *)led_bar1,8*3);	
						_delay_ms(1);

						}*/
						/*led_bar1[0].r=0;led_bar1[0].g=100;led_bar1[0].b=10;
						ws2812_sendarray((uint8_t *)led_bar1,8*3);
						_delay_ms(50);	
						led_bar1[0].r=255;led_bar1[0].g=0;led_bar1[0].b=10;
						ws2812_sendarray((uint8_t *)led_bar1,8*3);	*/

						
//				}



   return 0;                 
}

int map(int value, int old_min, int old_max,int new_min, int new_max)
{
		return (new_max/old_max*value);
}