If I directly sample through the 7 analog pins in beaglebone through pru and electret mics, will I get similar performance. I am getting too much noise in this kid of recording
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. What are the main reasons ? I am just trying to understand what kind of modifications Bela doing to make the audio cleaner ?
PRU Code:
#include <sys/time.h>
#include "../libpruio-0.2/src/c_wrapper/pruio.h"
#include "../libpruio-0.2/src/c_wrapper/pruio_pins.h"
#include <time.h>
#include <unistd.h>
#include <stdio.h>
 
 
int isleep(unsigned int mseconds)
{
  fd_set set;
  struct timeval timeout;
 
  /* Initialize the file descriptor set. */
  FD_ZERO(&set);
  FD_SET(STDIN_FILENO, &set);
 
  /* Initialize the timeout data structure. */
  timeout.tv_sec = 0;
  timeout.tv_usec = mseconds * 1000;
 
  return 1;
  //return TEMP_FAILURE_RETRY(select(FD_SETSIZE,
    //                               &set, NULL, NULL,
      //                             &timeout));
}
 
//! The main function.
int main(int argc, char **argv)
{
  pruIo *io = pruio_new(PRUIO_DEF_ACTIVE, 0x98, 0, 1); //! create new driver structure
  //pruIo *io = pruio_new(io, 0, 0, 0); 
  do { //                                      pseudo loop to avoid goto
    if (io->Errr) {
               printf("initialisation failed (%s)\n", io->Errr); break;}
 
    if (pruio_config(io, 1, 0x1FE, 0, 4)) {
                       printf("config failed (%s)\n", io->Errr); break;}
 
    //struct termios oldt, newt; //             make terminal non-blocking
    //tcgetattr( STDIN_FILENO, &oldt );
    //newt = oldt;
    //newt.c_lflag &= ~( ICANON | ECHO );
    //newt.c_cc[VMIN] = 0;
   // newt.c_cc[VTIME] = 0;
    //tcsetattr(STDIN_FILENO, TCSANOW, &newt);
    time_t secondsStart;
    time_t secondsNow;
 
    FILE* oFile;
    //uint8 bDiv = 4, bStep;
    //uint32 bSize = 1e6;
    //uint32 bsSize = bSize/bDiv;
    oFile = fopen("output.txt","w");
  
    secondsStart = time(0);
    int count_c=0;
    printf("Start Time: %lld\n",(long long)secondsStart);
 
  //  while(!isleep(1)) { //    run loop until keystroke
    while(count_c<2000000){
      //printf("%d %d %d %d %d %d %d\n", io->Adc->Value[0],io->Adc->Value[1],io->Adc->Value[2],io->Adc->Value[3],io->Adc->Value[4],io->Adc->Value[5],io->Adc->Value[6],io->Adc->Value[7]);
      //int adc0 = io->Adc->Value[0];  
      //printf("%d\n",adc0);
      int adc1 = io->Adc->Value[1];  
      int adc2 = io->Adc->Value[2];  
      int adc3 = io->Adc->Value[3];  
      int adc4 = io->Adc->Value[4];
      int adc5 = io->Adc->Value[5];  
      int adc6 = io->Adc->Value[6];  
      int adc7 = io->Adc->Value[7];  
      int adc8 = io->Adc->Value[8];
      //int adc5 = io->Adc->Value[5];
      //int adc6 = io->Adc->Value[6];
      
      int adc [8] = { adc1, adc2, adc3, adc4, adc5, adc6, adc7, adc8 };
      
      //fflush(STDIN_FILENO);
      //printf("\r%4X %4X %4X %4X\n",io->Adc->Value[2], io->Adc->Value[3], io->Adc->Value[4], io->Adc->Value[5]);
      //usleep(1);
      
      //fwrite(adc, sizeof(int), sizeof(adc), oFile);
      //fwrite("\n", sizeof(char), 1, oFile);
      
      secondsNow= time(0);
      //(long long)secondsNow,
      fprintf(oFile, "%d %d %d %d %d %d %d %d\n", adc[0], adc[1], adc[2], adc[3], adc[4], adc[5], adc[6], adc[7]);
      count_c++;
     
 
    }
    secondsNow= time(0);
    fclose(oFile);
    printf("Start Time: %lld\n",(long long)secondsStart);
    printf("End Time: %lld\n",(long long)secondsNow);
    printf("COUNT IS: %d\n",count_c );
    //tcsetattr(STDIN_FILENO, TCSANOW, &oldt); //           reset terminal
 
    printf("\n");
  } while (0);
 
  pruio_destroy(io);       /* destroy driver structure */
	return 0;
}