/****
	This program allows you to interactively capture a series of data from the
	analog inputs of the NIDAQ board. It queries you for the analog channel,
	the total number of samples to take, and the number of samples per second.
	The program then writes out the data to the screen.
****/
/****
	These are include files. They contain data types and 
	function prototypes that the compiler needs for your
	program.
****/
#include <stdio.h>			       // standard C I/O library
#include <nidaq.h>			       // Acquisition board library include file

/****
	These are constants that should be easy to set for the
	entire program.
****/
#define MAXDATA 1000			       // Maximum number of data points
#define BOARD 1				       // The slot in which the board resides (should be 1)
#define GAIN 1				       // An integer that determines, in part, the gain on analog
					       // inputs


/****
	The main program starts here
****/
main()
{
  // Variable declarations
  i16             channel,	// which I/O channel to use
                  timebase,	// timing base
                  errNum,	// error detection
                  values[MAXDATA],	// binary values read from the I/O board
                  units = 0,	// pts/s (0) or s/pt (1)
                  devNumCode;	// device number code

  long            count;	// how many samples to take

  u16             sampleInterval;	// sampling interval

  unsigned long   retrieved;	// Boolean value indicating when the sampling is finished

  short           status;	// status variable

  f64             rate,		// samples per second
                  voltages[MAXDATA];	// Final floating point voltages

  FILE           *fp;		// file pointer

  long            i;		// generic loop variable

  char            filename[128];	// filename for output data

  // Get the sampling setup information from the user
  printf("Capture program starting.\n\n");
  printf("Which analog input pin do you want to use? ");
  channel = -1;
  while (channel < 0 || channel > 7) {
    scanf("%hd", &channel);
    if (channel < 0 || channel > 7) {
      printf("The analog input pin must be between 0 and 7\n");
      printf("Please enter a new value: ");
    }
  }
  printf("\nUsing analog input channel: %hd\n\n", channel);

  printf("How many samples do you want to take? ");
  count = -1;
  while (count < 0 || count > MAXDATA) {
    scanf("%d", &count);
    if (channel < 0 || channel > MAXDATA) {
      printf("The number of samples must be between 0 and %d\n", MAXDATA);
      printf("Please enter a new value: ");
    }
  }
  printf("\nCapturing %d samples\n\n", count);

  printf("How many samples per second do you want to take? ");
  rate = -1.0;
  while (rate < 0.0) {
    scanf("%lf", &rate);
    if (rate < 0.0) {
      printf("The rate in samples/sec must be positive\n");
      printf("Please enter a new value: ");
    }
  }
  printf("\nUsing a sampling rate of %lf samples per second\n\n", rate);

  // This routine calculates the internal parameters timebase and sampleinterval
  status = DAQ_Rate(rate, units, &timebase, &sampleInterval);

  printf("(timebase, sampleInterval) = (%hd, %uhd)\n", timebase, sampleInterval);

  // Reset board, clear analog io and check for errors 
  errNum = Init_DA_Brds(BOARD, &devNumCode);
  if (errNum != 0) {
    printf("Init_DA_Brds: errNum %d          devNumCode %d\n", errNum, devNumCode);
    exit(0);
  }

  errNum = AI_Clear(BOARD);
  if (errNum != 0) {
    printf("AI_Clear: errNum %d          devNumCode %d\n", errNum,
devNumCode);
    exit(0);
  }

  // Start the data capture
  printf("Starting data capture\n");
  errNum = DAQ_Start(BOARD, channel, GAIN, values, count, timebase, sampleInterval);

  // Wait for acquisition to complete, or an error
  status = 0;
  while ((status == 0) && (errNum == 0)) {
    errNum = DAQ_Check(BOARD, &status, &retrieved);
    // retrieved holds the number of samples collected so far
    // The value if retrieved > 0, then (retrieved - 1) holds the latest sample
  }
  printf("Data collection is done, errNum=%d.\n", errNum);

  // Scale the data - ie convert it to voltages.
  errNum = DAQ_VScale(BOARD, channel, GAIN, 1.0, 0.0, count, values, voltages);

  // Write out your results to the screen here
  printf("# Analog Capture: %ld samples taken at %lf samples per second\n", count, rate);
  for (i = 0; i < count; i++)
    printf("%6d %12lf\n", i, voltages[i]);

  return(0);
}