da.c

rt 7520采集卡 linux驱动源代码

/*
	FILE NAME: da.c

	FILE DESCRIPTION:

		D/A conversion without DMA.  Samples are loaded directly into
		the DAC1 and DAC2 FIFO.  The samples are used for waveform
		generation.  DAC1 generates a square wave and DAC2 generates a
		complex wave form consisting of three sine periods with
		different amplitudes

		If 'r' is passed in as the second command line argument, the
		D/A FIFOs are reset whenever two-thirds of the waveform has
		been generated.  The D/A 1 Update Counter is used to keep track
		of the number of conversions.  When operating in this manner,
		the same wave forms are generated but one-third of their length
		is cut off.  SyncBus signals control D/A conversion.

	PROJECT NAME: Linux DM7520 Driver, Library, and Example Programs

	PROJECT VERSION: (Defined in README.TXT)

	Copyright 2004 RTD Embedded Technologies, Inc.  All Rights Reserved.
*/

#include <stdio.h>	//printf
#include <unistd.h>	//sleep
#include <errno.h>	//errno
#include <stdlib.h>	//exit
#include <math.h>	//sin
#include "dm7520_library.h"

#define DABUFFERSIZE	1000	//can not be more then FIFO size

//resetDAFIFOs
//this function is used in resetDA mode to reset DA FIFO
int wave = 0;
int devno;
void resetDAFIFOs(void) {
    ResetDAC1Fifo7520(devno);
    ResetDAC2Fifo7520(devno);
    wave++;
}


int main(int argc, char * argv[])
{
 FILE * infile;
 int i;
 short sample;
 float fok,val;
 int resetDA = 0;

 if (argc<2) {fprintf(stderr,"Usage: %s <device> [r]\n",argv[0]);exit(1);}
 if (3==argc) {
    if ('r' == *(argv[2])) {	// reset mode
	resetDA = 1;
    }
 }

 if (NULL==(infile=fopen(argv[1],"r"))) //open device. Enough to open for reading only
   {
    fprintf(stderr,"Cannot open file, errno=%d\n",errno);
    perror("Error is");
    exit(2);
   }

   devno = fileno(infile);		// device handler
 	InitBoard7520(devno);		//Initialize the device
	ClearDAC1Fifo7520(devno);
	ClearDAC2Fifo7520(devno);

    sample=2047<<3;
// set up the buffer for the first half of wave form 1
   for (i=0;i<DABUFFERSIZE/2;i++){
      WriteDac1Fifo7520(devno,sample); // load to fifo DAC1
   }
  sample=(-2047)<<3;
// set up the buffer for the second half of wave form 1
   for (i=0;i<DABUFFERSIZE/2;i++){
      WriteDac1Fifo7520(devno,sample); // load to fifo DAC1
   }

// set up the buffer for the wave form 2
   for (i=0;i<DABUFFERSIZE;i++) {
      fok =(float)i*(2*M_PI/(float)DABUFFERSIZE);
      val=sin(fok)+sin(fok*3)+sin(fok*5)+sin(fok*7)+sin(fok*9);
      sample=((int16_t)(2047*val/5.))<<3;
      WriteDac2Fifo7520(devno,sample); // load to fifo DAC2
   }


 
 if (resetDA) {
    SetupDAC7520(devno,DM7520_WRITE_DA1,AOUT_BIP5,DAC_CYCLE_MULTI,DAC_START_SBUS1); // set up wave form1
    SetupDAC7520(devno,DM7520_WRITE_DA2,AOUT_BIP5,DAC_CYCLE_MULTI,DAC_START_SBUS2); //set up wave form 2
    SetUtc2Clock7520(devno, CUTC2_8MHZ);
    SetupSbus7520(devno,1, SBUS1_UTC2,1);
    SetupSbus7520(devno,2, SBUS2_UTC2,1); 
    Set8254Mode7520(devno, TC_UTC2, M8254_SQUARE_WAVE);
    Set8254Divisor7520(devno, TC_UTC2,8000000/10000);	//start da coversion at 10 kHz 
 
    wave = 0;
    LoadUcnt17520(devno,DABUFFERSIZE*2/3);
    SetNotification7520(devno, (unsigned short) IRQS_DAC1_UCNT,resetDAFIFOs);
    while (wave<200); 	// generate 200 periods of the wave form
    UnSetNotification7520(devno);
 }
 else {
    SetupDAC7520(devno,DM7520_WRITE_DA1,AOUT_BIP5,DAC_CYCLE_MULTI,DAC_START_DAC_CLK); // set up wave form1
    SetupDAC7520(devno,DM7520_WRITE_DA2,AOUT_BIP5,DAC_CYCLE_MULTI,DAC_START_DAC_CLK); //set up wave form 2
    SetDACRate7520(devno, 10000);	//start da coversion at 10 kHz
    
    sleep(10); 	// generate waveforms for 10 seconds
 }	
 fclose(infile);	// close device
 return(0);
}