sbpcd

《嵌入式系统设计与实例开发实验教材二源码》Linux内核移植与编译实验

Once activated, it does not stop before success or end-of-list. This may be
useful within "universal" CDROM installation boot floppies (but using the 
loadable module would be better because it allows an "extended" auto-probing
without fearing NE2000 cards).

To shorten the auto-probing list to a single entry, set DISTRIBUTION 0 within
sbpcd.h.


Setting up address and interface type:
--------------------------------------

If your I/O port address is not 0x340, you have to look for the #defines near
the beginning of sbpcd.h and configure them: set SBPRO to 0 or 1 or 2, and
change CDROM_PORT to the address of your CDROM I/O port.

Almost all of the "SoundBlaster compatible" cards behave like the no-sound
interfaces, i.e. need SBPRO 0! 

With "original" SB Pro cards, an initial setting of CD_volume through the
sound card's MIXER register gets done.
If you are using a "compatible" sound card of types "LaserMate" or "SPEA",
you can set SOUND_BASE (in sbpcd.h) to get it done with your card, too...


Using audio CDs:
----------------

Workman, WorkBone, xcdplayer, cdplayer and the nice little tool "cdplay" (see
README.aztcd from the Aztech driver package) should work.

The program CDplayer likes to talk to "/dev/mcd" only, xcdplayer wants
"/dev/rsr0", workman loves "/dev/sr0" or "/dev/cdrom" - so, make the 
appropriate links to use them without the need to supply parameters.


Copying audio tracks:
---------------------

The following program will copy track 1 (or a piece of it) from an audio CD
into the file "track01":

/*=================== begin program ========================================*/
/*
 * read an audio track from a CD
 *
 * (c) 1994 Eberhard Moenkeberg <[e-mail]>
 *          may be used & enhanced freely
 *
 * Due to non-existent sync bytes at the beginning of each audio frame (or due
 * to a firmware bug within all known drives?), it is currently a kind of
 * fortune if two consecutive frames fit together.
 * Usually, they overlap, or a little piece is missing. This happens in units
 * of 24-byte chunks. It has to get fixed by higher-level software (reading
 * until an overlap occurs, and then eliminate the overlapping chunks). 
 * ftp.gwdg.de:/pub/linux/misc/cdda2wav-sbpcd.*.tar.gz holds an example of
 * such an algorithm.
 * This example program further is missing to obtain the SubChannel data
 * which belong to each frame.
 *
 * This is only an example of the low-level access routine. The read data are
 * pure 16-bit CDDA values; they have to get converted to make sound out of
 * them.
 * It is no fun to listen to it without prior overlap/underlap correction!
 */
#include <stdio.h>
#include <sys/ioctl.h>
#include <linux/cdrom.h>

static struct cdrom_tochdr hdr;
static struct cdrom_tocentry entry[101];
static struct cdrom_read_audio arg;
static u_char buffer[CD_FRAMESIZE_RAW];
static int datafile, drive;
static int i, j, limit, track, err;
static char filename[32];

main(int argc, char *argv[])
{
/*
 * open /dev/cdrom
 */
  drive=open("/dev/cdrom", 0);
  if (drive<0)
    {
      fprintf(stderr, "can't open drive.\n");
      exit (-1);
    }
/*
 * get TocHeader
 */
  fprintf(stdout, "getting TocHeader...\n");
  err=ioctl(drive, CDROMREADTOCHDR, &hdr);
  if (err!=0)
    {
      fprintf(stderr, "can't get TocHeader (error %d).\n", err);
      exit (-1);
    }
  else
    fprintf(stdout, "TocHeader: %d %d\n", hdr.cdth_trk0, hdr.cdth_trk1);
/*
 * get and display all TocEntries
 */
  fprintf(stdout, "getting TocEntries...\n");
  for (i=1;i<=hdr.cdth_trk1+1;i++)
    {
      if (i!=hdr.cdth_trk1+1) entry[i].cdte_track = i;
      else entry[i].cdte_track = CDROM_LEADOUT;
      entry[i].cdte_format = CDROM_LBA;
      err=ioctl(drive, CDROMREADTOCENTRY, &entry[i]);
      if (err!=0)
	{
	  fprintf(stderr, "can't get TocEntry #%d (error %d).\n", i, err);
	  exit (-1);
	}
      else
	{
	  fprintf(stdout, "TocEntry #%d: %1X %1X %06X %02X\n",
		 entry[i].cdte_track,
		 entry[i].cdte_adr,
		 entry[i].cdte_ctrl,
		 entry[i].cdte_addr.lba,
		 entry[i].cdte_datamode);
	}
    }
  fprintf(stdout, "got all TocEntries.\n");
/*
 * ask for track number (not implemented here)
 */
track=1;
#if 0 /* just read a little piece (4 seconds) */
entry[track+1].cdte_addr.lba=entry[track].cdte_addr.lba+300;
#endif
/*
 * read track into file
 */
  sprintf(filename, "track%02d\0", track);
  datafile=creat(filename, 0755);
  if (datafile<0)
    {
      fprintf(stderr, "can't open datafile %s.\n", filename);
      exit (-1);
    }
  arg.addr.lba=entry[track].cdte_addr.lba;
  arg.addr_format=CDROM_LBA; /* CDROM_MSF would be possible here, too. */
  arg.nframes=1;
  arg.buf=&buffer[0];
  limit=entry[track+1].cdte_addr.lba;
  for (;arg.addr.lba<limit;arg.addr.lba++)
    {
      err=ioctl(drive, CDROMREADAUDIO, &arg);
      if (err!=0)
	{
	  fprintf(stderr, "can't read abs. frame #%d (error %d).\n", 
		 arg.addr.lba, err);
	}
      j=write(datafile, &buffer[0], CD_FRAMESIZE_RAW);
      if (j!=CD_FRAMESIZE_RAW)
	{
	  fprintf(stderr,"I/O error (datafile) at rel. frame %d\n",
			 arg.addr.lba-entry[track].cdte_addr.lba);
	}
      arg.addr.lba++;
    }
}
/*===================== end program ========================================*/

At ftp.gwdg.de:/pub/linux/misc/cdda2wav-sbpcd.*.tar.gz is an adapted version of
Heiko Eissfeldt's digital-audio to .WAV converter (the original is there, too).
This is preliminary, as Heiko himself will care about it.


Known problems:
---------------

Currently, the detection of disk change or removal is actively disabled.

Most attempts to read the UPC/EAN code result in a stream of zeroes. All my
drives are mostly telling there is no UPC/EAN code on disk or there is, but it
is an all-zero number. I guess now almost no CD holds such a number.

Bug reports, comments, wishes, donations (technical information is a donation,
too :-) etc. to [e-mail].

SnailMail address, preferable for CD editors if they want to submit a free
"cooperation" copy:
                         Eberhard Moenkeberg
                         Reinholdstr. 14
                         D-37083 Goettingen
                         Germany
---


Appendix -- the "cdtester" utility:

/*
 * cdtester.c -- test the audio functions of a CD driver
 *
 * (c) 1995 Eberhard Moenkeberg <[e-mail]>
 *          published under the GPL
 *
 *          made under heavy use of the "Tiny Audio CD Player"
 *          from Werner Zimmermann <[e-mail]>
 *          (see linux/drivers/block/README.aztcd)
 */
#undef AZT_PRIVATE_IOCTLS /* not supported by every CDROM driver */
#define SBP_PRIVATE_IOCTLS /* not supported by every CDROM driver */

#include <stdio.h>
#include <stdio.h>
#include <malloc.h>
#include <sys/ioctl.h>
#include <linux/cdrom.h>

#ifdef AZT_PRIVATE_IOCTLS
#include <linux/../../drivers/cdrom/aztcd.h>
#endif AZT_PRIVATE_IOCTLS
#ifdef SBP_PRIVATE_IOCTLS
#include <linux/../../drivers/cdrom/sbpcd.h>
#include <linux/fs.h>
#endif SBP_PRIVATE_IOCTLS

struct cdrom_tochdr hdr;
struct cdrom_tochdr tocHdr;
struct cdrom_tocentry TocEntry[101];
struct cdrom_tocentry entry;
struct cdrom_multisession ms_info;
struct cdrom_read_audio read_audio;
struct cdrom_ti ti;
struct cdrom_subchnl subchnl;
struct cdrom_msf msf;
struct cdrom_volctrl volctrl;
#ifdef AZT_PRIVATE_IOCTLS
union
{
	struct cdrom_msf msf;
	unsigned char buf[CD_FRAMESIZE_RAW];
} azt;
#endif AZT_PRIVATE_IOCTLS
int i, i1, i2, i3, j, k;
unsigned char sequence=0;
unsigned char command[80];
unsigned char first=1, last=1;
char *default_device="/dev/cdrom";
char dev[20];
char filename[20];
int drive;
int datafile;
int rc;

void help(void)
{
	printf("Available Commands:\n");
	printf("STOP          s      EJECT        e       QUIT         q\n");
	printf("PLAY TRACK    t      PAUSE        p       RESUME       r\n");
	printf("NEXT TRACK    n      REPEAT LAST  l       HELP         h\n");
	printf("SUBCHANNEL_Q  c      TRACK INFO   i       PLAY AT      a\n");
	printf("READ          d      READ RAW     w       READ AUDIO   A\n");
	printf("MS-INFO       M      TOC          T       START        S\n");
	printf("SET EJECTSW   X      DEVICE       D       DEBUG        Y\n");
	printf("AUDIO_BUFSIZ  Z      RESET        R       BLKRASET     B\n");
	printf("SET VOLUME    v      GET VOLUME   V\n");
}

/*
 *  convert MSF number (3 bytes only) to Logical_Block_Address 
 */
int msf2lba(u_char *msf)
{
	int i;
	
	i=(msf[0] * CD_SECS + msf[1]) * CD_FRAMES + msf[2] - CD_BLOCK_OFFSET;
	if (i<0) return (0);
	return (i);
}
/*
 *  convert logical_block_address to m-s-f_number (3 bytes only)
 */
void lba2msf(int lba, unsigned char *msf)
{
	lba += CD_BLOCK_OFFSET;
	msf[0] = lba / (CD_SECS*CD_FRAMES);
	lba %= CD_SECS*CD_FRAMES;
	msf[1] = lba / CD_FRAMES;
	msf[2] = lba % CD_FRAMES;
}

int init_drive(char *dev)
{
	unsigned char msf_ent[3];

	/*
	 * open the device
	 */
	drive=open(dev,0);
	if (drive<0) return (-1);
	/*
	 * get TocHeader
	 */
	printf("getting TocHeader...\n");
	rc=ioctl(drive,CDROMREADTOCHDR,&hdr);
	if (rc!=0)
	{
		printf("can't get TocHeader (error %d).\n",rc);
		return (-2);
	}
	else
		first=hdr.cdth_trk0;
		last=hdr.cdth_trk1;
		printf("TocHeader: %d %d\n",hdr.cdth_trk0,hdr.cdth_trk1);
	/*
	 * get and display all TocEntries
	 */
	printf("getting TocEntries...\n");
	for (i=1;i<=hdr.cdth_trk1+1;i++)
	{
		if (i!=hdr.cdth_trk1+1) TocEntry[i].cdte_track = i;
		else TocEntry[i].cdte_track = CDROM_LEADOUT;
		TocEntry[i].cdte_format = CDROM_LBA;
		rc=ioctl(drive,CDROMREADTOCENTRY,&TocEntry[i]);
		if (rc!=0)
		{
			printf("can't get TocEntry #%d (error %d).\n",i,rc);
		}
		else
		{
			lba2msf(TocEntry[i].cdte_addr.lba,&msf_ent[0]);
			if (TocEntry[i].cdte_track==CDROM_LEADOUT)
			{
				printf("TocEntry #%02X: %1X %1X %02d:%02d:%02d (lba: 0x%06X) %02X\n",
				       TocEntry[i].cdte_track,
				       TocEntry[i].cdte_adr,
				       TocEntry[i].cdte_ctrl,
				       msf_ent[0],
				       msf_ent[1],
				       msf_ent[2],
				       TocEntry[i].cdte_addr.lba,
				       TocEntry[i].cdte_datamode);
			}
			else
			{
				printf("TocEntry #%02d: %1X %1X %02d:%02d:%02d (lba: 0x%06X) %02X\n",
				       TocEntry[i].cdte_track,
				       TocEntry[i].cdte_adr,
				       TocEntry[i].cdte_ctrl,
				       msf_ent[0],
				       msf_ent[1],
				       msf_ent[2],
				       TocEntry[i].cdte_addr.lba,
				       TocEntry[i].cdte_datamode);
			}
		}
	}
	return (hdr.cdth_trk1); /* number of tracks */
}