fd man page on Xenix

Man page or keyword search:  
man Server   1130 pages
apropos Keyword Search (all sections)
Output format
Xenix logo
[printable version]



     FD(HW)		      XENIX System V			FD(HW)

     Name
	  fd - floppy devices

     Description
	  The fd devices implement the	interface with floppy disk
	  drives.  Typically, the tar(C), cpio(C) or dd(C) commands
	  are used to read or write floppy disks.  For instance,

	       tar tvf /dev/fd0

	  tabulates the contents of the floppy disk in drive 0 (zero).

	  The block special fd devices are also block-buffered.	 The
	  floppy driver can read or write 512 bytes at a time using
	  raw i/o.  Note that block transfers are always a multiple of
	  the 1K disk block size.

	  The floppy devices are named /dev/fd0 and /dev/fd1 (see
	  Notes, below, for more information about device naming
	  procedure).

	  The corresponding character special (raw) devices, /dev/rfd0
	  and /dev/rfd1, afford direct, unbuffered transmission
	  between the floppy and the user's read or write transfer
	  address in the user's program.

	  For information about formatting, see format(C).

	  The minor device number determines what kind of physical
	  device is attached to each device file (see Notes).

     Files
	  /dev/fd0    /dev/rfd048ds8   /dev/rfd096ds15
	  /dev/fd1    /dev/rfd148ds8   /dev/rfd196ds15
	  /dev/rfd0   /dev/rfd048ds9   /dev/rfd096ds8
	  /dev/rfd1   /dev/rfd148ds9   /dev/rfd196ds8
				       /dev/rfd048ss8
				       /dev/rfd148ss9

     Notes
	  When accessing the character special floppy devices, the
	  user's buffer must begin on a word boundary.	The count in a
	  read(S), write(S), or lseek(S) call to a character special
	  floppy device must be a multiple of 512 bytes.

	  Device names determine the particular drive and media
	  configuration.  The device names have the form: fd048ds9
	  Where: fd0 = drive number (0, 1, 2 or 3) 48  = number of
	  disk tracks per inch (48 or 96) ds  = single or double sided
	  floppy (ss or ds) 9	= number of sectors on the floppy (8
	  or 9)

     Page 1					      (printed 8/7/87)

     FD(HW)		      XENIX System V			FD(HW)

	  For instance, /dev/fd048ss9 indicates a 48 track per inch,
	  single sided, 9 sector floppy disk device in drive 0.

	  The minor device numbers for floppy drives depend on the
	  drive and media configuration.  The most common are:

	       __________________________________________________
	      |		      48tpi		 |     96tpi	|
	      |		ds/8   ds/9   ss/8   ss/9|  ds/15   ds/8|
	      |______|__________________________________________|
	      | Drive|		  Minor Device Number		|
	      |______|______|______|______|______|_______|______|
	      |	 0   |	 12 |	4  |   8  |   0	 |   52	 |   44 |
	      |	 1   |	 13 |	5  |   9  |   1	 |   53	 |   45 |
	      |	 2   |	 14 |	6  |   10 |   2	 |   54	 |   46 |
	      |	 3*  |	    |	   |	  |	 |	 |	|
	      |	     |	    |	   |	  |	 |	 |	|
	      |______|______|______|______|______|_______|______|

	  *    reserved for special, non-floppy devices connected to
	       the floppy controller as unit #3.

	  The scheme for creating minor device numbers is as follows.
	  When interpreted as a binary number, each bit of the minor
	  device number represents some aspect of the device/media
	  configuration.

	  For example, the minor device number for /dev/fd048ss8 is
	  ``8.'' Interpreted as a binary number, 8 is:

	       00001000

	  This is how each bit, or binary digit, is significant:

     _______________________________________________________________________
    | 48tpi - 0|       Sectors per     |  ss - 0   |			   |
    |__________|		       | __________|	      Drive	   |
    | 96tpi - 1|	  Track	       |  ds - 1   |			   |
    |__________|_______________________|___________|_______________________|
    |	 32    |     16		  8    |      4	   |	  2	      1	   |
    |__________|___________|___________|___________|___________|___________|
    |	  0    |      0	   |	  1    |      0	   |	  0    |      0	   |
    |	       |	   |	       |	   |	       |	   |
    |__________|___________|___________|___________|___________|___________|

     Page 2					      (printed 8/7/87)

     FD(HW)		      XENIX System V			FD(HW)

	  Only the last six digits of the number are used in minor
	  device identification. The first significant digit is the
	  third from the left.	In this example, the third digit from
	  the left is zero, thus the device is 48tpi.  The next two
	  digits mean:

			     ______________________
			    |	    |  Sectors per|
			    |  Bits |	  Track	  |
			    |___|___|		  |
			    | 16|  8|		  |
			    |___|___|_____________|
			    | 0 |  0|	    9	  |
			    | 0 |  1|	    8	  |
			    | 1 |  0|	   15	  |
			    |___|___|_____________|

	  The fourth digit tells whether the floppy is single sided
	  (ss - 0) or double sided (ds - 1).  The last two signify the
	  drive number:

				________________
			       |      |	 Drive |
			       | Bits |	 Number|
			       |__|___|	       |
			       | 2|  1|	       |
			       |__|___|________|
			       | 0|  0|	   0   |
			       | 0|  1|	   1   |
			       | 1|  0|	   2   |
			       | 1|  1|	   3*  |
			       |__|___|________|

	  *    reserved for special, non-floppy devices connected to
	       the floppy controller as unit #3.

	  Using this information, you can construct any minor device
	  numbers you need.

	  It is not advisable to format a low density (48tpi) diskette
	  on a high density (96tpi) floppy drive. Low density
	  diskettes written on a high density drive should be read on
	  high density drives. They may or may not be readable on a
	  low density drive.

	  Use error-free floppy disks for best results on reading and
	  writing.

     Page 3					      (printed 8/7/87)

[top]
                             _         _         _ 
                            | |       | |       | |     
                            | |       | |       | |     
                         __ | | __ __ | | __ __ | | __  
                         \ \| |/ / \ \| |/ / \ \| |/ /  
                          \ \ / /   \ \ / /   \ \ / /   
                           \   /     \   /     \   /    
                            \_/       \_/       \_/ 
More information is available in HTML format for server Xenix

List of man pages available for Xenix

Copyright (c) for man pages and the logo by the respective OS vendor.

For those who want to learn more, the polarhome community provides shell access and support.

[legal] [privacy] [GNU] [policy] [cookies] [netiquette] [sponsors] [FAQ]
Tweet
Polarhome, production since 1999.
Member of Polarhome portal.
Based on Fawad Halim's script.
....................................................................
Vote for polarhome
Free Shell Accounts :: the biggest list on the net