gpioanalyser/main.cpp

#define _POSIX_C_SOURCE 199309L
#include <sys/time.h>
#include <time.h>
#include <iostream>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <signal.h>

#include "gpio-raw.h"


volatile unsigned n = 350000000 / sizeof(unsigned char);

void signal_handler(int signo)
{
  std::cout << "signal catched" << std::endl;
  n = 0;
}

int main(int argc, char* argv[])
{
  setup_io();
  INP_GPIO(4);

  struct timeval t1, t2;
  unsigned char* v = new unsigned char[n];
  unsigned count = 0;
  std::cout << "Ready to sniff. Press enter...";
  getchar();

  signal(SIGINT, signal_handler);
  gettimeofday(&t1, NULL);
    for (; count < n; ++count)
    {
      const unsigned value = GPIO_LEV;
      v[count] = GPIO_VALUE_R(value, 6) | (GPIO_VALUE_R(value, 26) << 1);
    }
  gettimeofday(&t2, NULL);
  signal(SIGINT, SIG_DFL);

  unsigned long long ut1 = (__suseconds_t)(1000000L * t1.tv_sec + t1.tv_usec);
  unsigned long long ut2 = (__suseconds_t)(1000000L * t2.tv_sec + t2.tv_usec);
  unsigned long long diff = ut2 - ut1;
  double unit = (double)diff / count;
  double mhz = (1000000.0 / unit) / 1000000.0;
  std::cout << "count: " << count << " diff: " << diff << " unit: "
    << unit << " Mhz: " << mhz << std::endl;

  std::cout << "Saving file..." << std::endl;
  int fd = open("gpio.out", O_CREAT | O_WRONLY);
  write(fd, (void*)v, count * sizeof(*v));
  close(fd);
  return 0;
}