hd_dma.c

rt 7520采集卡 linux驱动源代码

/*
	FILE NAME: hd_dma.c

	FILE DESCRIPTION:

		Demonstrates how to use on demand DMA with high speed digital
		input.

		Samples are read into a buffer and then displayed on the
		screen.

		User Timer Counter 0 is used to initiate sampling.

		Please note that high speed digital input DMA internally uses
		User Timer Counter 1 so you cannot use it for anything else.

	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 <stdlib.h>	//exit
#include <errno.h>	//errno
#include "dm7520_library.h"

#define BUFSIZE 20480
#define RATE 50000	//input rate in Hz

int main(int argc, char * argv[])
{
 FILE * infile;
 int16_t buffer [BUFSIZE];
 int cnt,i;
 uint16_t fifostat;
 int err;
 int devno;		//device handler
 int useDMA  = 0;
 int errorCode=0;
 uint8_t	bus_master;



 if (argc<2) {fprintf(stderr,"Usage: %s <device> \n",argv[0]);exit(1);}

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

 
   devno = fileno(infile);		// get device handler

 IsBusMaster7520(devno, &bus_master);
 if (bus_master) {
    printf("Busmaster card\n");
    useDMA=1;
 }
 else {
    printf("Non-busmaster card\n");
 }

 InitBoard7520(devno);     // init the board

 SetUtc0Clock7520 (devno, CUTC0_8MHZ);
 Set8254Mode7520(devno, TC_UTC0, M8254_RATE_GENERATOR ) ;
 SetUtc0Gate7520 (devno, GUTC0_NOT_GATED );
  
 SetHdinStart7520 ( devno, 2) ;	//get samples on HSDIO on user TC0


 GetFifoStatus7520(devno, &fifostat);
 printf("\nFIFO status: %04X.\n",fifostat);

 if (useDMA) {
     err = SetHD_DMAMode7520(devno,0);
    if (err < 0) printf("ERROR: could not set DMA mode \n");
    else printf("DMA started \n");
 }
 ClearDinFifo7520(devno);
 Set8254Divisor7520 (devno, TC_UTC0,(uint16_t)(8000000L/RATE) ); //set TC0 rate
 cnt=ReadData7520(devno,buffer,BUFSIZE);

 printf("got data\n");
 if (cnt !=BUFSIZE) {
	 GetErrorCode7520(devno, &errorCode);
	 printf("ERROR while reading data read byte = %d\nError code=%d\n", cnt, errorCode);
	 ClearErrorCode7520(devno);
 }
 
 if (useDMA) {
    err = UnSetDMAMode7520(devno, 0);
    if (err<0) printf("ERROR: could not unset DMA mode \n");
 }
 printf("read %d samples\n", cnt);

 printf("Raw samples:");
 for (i=0;i<(cnt);i++)
   {
    if (0==i%16) printf("\n");
    printf("%2X  ", (buffer[i]) & 0xFF);
   }
 printf("\n");


 fclose(infile);
 return(0);
}