DAC test in MATRIX Voice

DAC.cpp

/*
 * Copyright 2017 <Admobilize>
 * All rights reserved.
 */

#include <gflags/gflags.h>
#include <wiringPi.h>

#include <math.h>
#include <fstream>
#include <iostream>
#include <string>
#include <thread>
#include <valarray>

#include "../cpp/driver/everloop.h"
#include "../cpp/driver/everloop_image.h"
#include "../cpp/driver/microphone_array.h"
#include "../cpp/driver/wishbone_bus.h"


DEFINE_int32(sampling_frequency, 44100, "Sampling Frequency");
DEFINE_int32(duration, 1, "Interrupt after N seconds");

namespace hal = matrix_hal;

int main(int argc, char *agrv[]) {
  google::ParseCommandLineFlags(&argc, &agrv, true);

  hal::WishboneBus bus;
  bus.SpiInit();

  int sampling_rate = FLAGS_sampling_frequency;
  int seconds_to_record = FLAGS_duration;
  std::cout << "Duration : " << seconds_to_record << "s" << std::endl;

  std::thread et(
      [seconds_to_record, sampling_rate](hal::WishboneBus *bus) {

        std::ifstream is("/home/pi/song.raw");

        int delta, t;
	int l = 1024;
        uint16_t test[l];
        
        float fs = float(sampling_rate);
        float ts = 1.0 / fs;
        float f = 1000;
        float w = 2 * M_PI * f;
        float A = (pow(2, 16)) - 1;
	t=0;
              

	while (true) {
          delta = (t) * l;
         // for (int i = 0; i < l; i++) {
         //   test[i] = uint16_t(A/2 + A*sin(w*(delta+i)*ts)/128);
         // }
          is.read((char *)test,l*2);
          uint16_t write_pointer;
	  uint16_t read_pointer;
          uint16_t diff;
	  bus->SpiRead16(0x6802,(unsigned char*)&read_pointer);
	  bus->SpiRead16(0x6803,(unsigned char*)&write_pointer);
          
	  if(write_pointer > read_pointer)
		  diff = write_pointer - read_pointer;
	  else
		  diff = 4096 - read_pointer + write_pointer;

	  if(diff > 3072){
	      int sleep = int(l*ts*1000000);
 	      std::this_thread::sleep_for(std::chrono::microseconds(sleep));
	  }
	  bus->SpiWriteBurst(0x6000,
                             reinterpret_cast<unsigned char *>(&test[0]),
                             sizeof(uint16_t) * l);

          t++;
        }
      },
      &bus);

  et.join();

  return 0;
}