Floppy Minor Device Numbers for V/AT

[Wolf N. Paul]

In response to my recent posting asking for information about System V/AT
floppy driver minor device numbers, a number of people sent me information,
and after checking it all out with Microport Tech Support, I compiled the 
following information, which is here presented in the form of a
C language header file.

I hope it proves helpful to someone.

John Sully said that a revised fl(7) manual page was supposed to
go out with 2.4, but was somehow omitted; he promised to post it to the
Uport BBS in the near future. In the meantime, here's this.
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/*
 * floppy.h
 * Floppy Drive Minor Number Bit Definitions for System V/AT
 */

/*
 * Compiled by Wolf N. Paul (dcs!wnp at killer.dallas.tx.us)
 * based on information from Mark Zenier (markz at ssc.uucp) and
 * John Sully (jmsully at uport).
 *
 * This information is correct to the best of my knowledge, but
 * I make no warranties as to its correctness or usefulness for
 * any purpose. Use at your own risk (in other words, experiment
 * with it before relying on it!).
 *
 * I hope this information is helpful to someone. Comments and corrections
 * (but not flames) are welcome.
 *
 * Thu Dec 22 19:46:43 CST 1988 wnp at dcs.uucp
 */

/*
 * Layout of Bits in Floppy Device Minor Numbers:
 *
 *	              *	Bit 0: 0=8 sectors/track,      1=9 sectors/track
 *	            * |	Bit 1: 0=single sided,         1=doublesided
 *	          * | | Bit 2: 0=40 cylinders          1=80 cylinders
 *	        * | | | Bit 3: 0=Drive 0 (A:)          1=Drive 1 (B:)
 *	      * | | | | Bit 4: 0=HD (500 kbps)         1=DD
 *	    * | | | | | Bit 5: 0=5.25" Drive           1=3.5" Drive
 *	  * | | | | | | Bit 6: 0=doublestep            1=singlestep 
 *	* | | | | | | | Bit 7: 0=start on cyl 0        1=start on cyl 1
 *	| | | | | | | |
 *	| | | | | | | |   Min. Microport Names             Name at dcs Note
 *	0 1 0 0 0 1 1 0 =  70  fd, fd096, fd096ds15, 0s24    fd0hd
 *	0 0 0 1 0 1 1 1 =  23  fd048, fd048ds9               fd0dd  (HD Drive)
 *	0 1 0 1 0 0 1 1 =  83  fd048, fd048ds9               fd0dd  (DD Drive)
 *	0 1 0 1 0 1 1 1 =  87  fd096ds9                      fd0qd  (5.25")
 *	0 1 1 1 0 1 1 1 = 119  fd0mf2dd                      fd0qd  (3.5")
 *      0 1 1 0 0 1 1 0 = 102  fd0mf2hd                      fd0xd
 *
 *	0 1 0 0 1 1 1 0 =  78  fd196, fd196ds15              fd1hd
 *	0 0 0 1 1 1 1 1 =  31  fd148, fd148ds9               fd1dd  (HD Drive)
 *	0 1 0 1 1 0 1 1 =  91  fd148, fd148ds9               fd1dd  (DD Drive)
 *	0 1 0 1 1 1 1 1 =  95  fd196ds9                      fd1qd  (5.25")
 *	0 1 1 1 1 1 1 1 = 127  fd1mf2dd                      fd1qd  (3.5")
 *      0 1 1 0 1 1 1 0 = 110  fd1mf2hd                      fd1xd
 *
 *	1 1 0 0 0 1 1 0 = 198  0s25	5.25" high density installit, drive 0
 *      1 1 0 0 1 1 1 0 = 206  ????     5.25" high density installit, drive 1
 *	1 1 1 0 0 1 1 0 = 230  ????     3.5"  high density installit, drive 0
 *	1 1 1 0 1 1 1 0 = 238  ????     3.5"  high density installit, drive 1
 *
 * Some variations in these numbers can occur because certain bits override
 * other bits; i.e., unless bit 3 is 0 (HD, 15tps, 500 kbps), the setting of
 * bit 0 (9 tps) is irrelevant, it can be on or off without effect.
 *
 * The names for devices given in the "Name at dcs" column are the names I use
 * on my system; I find them more mnemonic than the names on the Microport
 * distribution floppies:
 *
 * dd=double density, 360K; qd=quad density, 720K; hd=high density, 1.2M; and
 * xd=eXtra high density, 1.44M.
 *
 * If I ever need names for "installit" floppies other than 0s25, I will 
 * probably use the same names, substituting "if" for "fd".
 *
 */

#define FLMIN_9SECTOR	  1
#define FLMIN_DBLSIDE	  2
#define FLMIN_80TRACK	  4
#define FLMIN_UNITNUM	  8
#define FLMIN_DBLDENS	 16
#define FLMIN_MICROFL	 32
#define FLMIN_SGLSTEP	 64
#define FLMIN_FSOFFST	128
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-- 
Wolf N. Paul * 3387 Sam Rayburn Run * Carrollton TX 75007 * (214) 306-9101
UUCP:     killer!dcs!wnp                 ESL: 62832882
DOMAIN:   dcs!wnp at killer.dallas.tx.us    TLX: 910-380-0585 EES PLANO UD