---

di_simplest.c

Go to the documentation of this file.

#include <sys/types.h>

#include <stdlib.h>
#include <math.h>
#include <unistd.h>
#include <stdint.h>

#include "di194.h"

bool do_exit;

// ---------------------------------------------------------------------
void sighandler(int signal)
{
    char    me[] = "sighandler";

    fprintf(stderr, "\n%s: Got signal %d, exiting\n", me, signal);
    fflush(stderr);
    
    do_exit = true;

    return;
}

//***********************************************************************
int main(int argc, char *argv[])
{
    int           rc;
    daq_reading_t data;
    int           DI_FD = -1;
    time_t       last_read, delta_t;
    int          num_bits = 8;


    printf("\nInstalling signal handler.");
    do_exit = false;
    signal(SIGINT, sighandler);
    signal(SIGPIPE, sighandler);

    printf("\nOpening device");
    fflush(stdout);

    DI_FD = di_open(NULL, &num_bits);
    if(DI_FD <= 0)
    {
        fprintf(stderr, "\nError %d opening device\n", rc);
        di_close(DI_FD);
 
        return(rc);
    }

    printf("\nStarting DAQ running, we have %d bits of precision", 
           num_bits);
    
    rc = di_start(DI_FD);
    if(rc != 0)
    {
        fprintf(stderr, "\nError %d starting DAQ\n", rc);
        di_close(DI_FD);
 
        return(rc);
    }

    // Paranoia, not really required
    rc = di_daq_sync(DI_FD);
    if(rc != 0)
    {
        fprintf(stderr, "\nError %d syncing DAQ\n", rc);
        di_close(DI_FD);

        return(rc);
    }

    last_read = time(NULL);
    
    // Loop until signal handler sets 'do_exit' flag on ctrl-c
    while(do_exit == false)
    {
        // Read data from DI-194
        rc = di_read(DI_FD, &data, num_bits);
        if(rc != 0)
        {
            fprintf(stderr, "\nError %d reading data", rc);
            break;
        }

        // Print out latest data once per second
        delta_t = time(NULL) - last_read;
        if(delta_t > 0)
          {
            printf("\n%5.2f %5.2f %5.2f %5.2f %1d %1d %1d",
                   data.analog[0],
                   data.analog[1],
                   data.analog[2],
                   data.analog[3],
                   data.digital[0],
                   data.digital[1],
                   data.digital[2]);
            /*
            printf("%5.2f (%d) %5.2f (%d) %5.2f (%d) %5.2f (%d) %1d %1d %1d\n",
                   data.analog[0], data.raw[0],
                   data.analog[1], data.raw[1],
                   data.analog[2], data.raw[2],
                   data.analog[3], data.raw[3],
                   data.digital[0],
                   data.digital[1],
                   data.digital[2]);
            */
            last_read = time(NULL);
            fflush(stdout);
          }
   }

    di_close(DI_FD);
    return(0);
}

---