Skip site navigation (1)Skip section navigation (2)

FreeBSD Manual Pages


home | help
FDC(4)		       FreeBSD Kernel Interfaces Manual			FDC(4)

     fdc -- PC architecture floppy disk	controller driver

     device fdc0 at isa? port IO_FD1 flags 0x1 irq 6 drq 2
     device fd0	at fdc0	drive 0
     device fd1	at fdc0	drive 1

     This driver provides access to floppy disk	drives and QIC40/80
     tapedrives.  In /dev for each floppy device a number of minor devices are
     present.  The /dev/fd* devices with trailing alphabetic characters	are
     used to indicate `partitions' on the floppy disk.	The /dev/fd*.<number>
     are devices that indicate the size	of the floppy disk (so:	720kB, 1440kB
     etc). The latter are used for formatting disks using fdformat or for
     accessing different density disks in multidensity drive.  Example:	720kB
     disk in a 1.44Mb drive.

     Normally, the driver will ask the system's	CMOS memory to obtain the
     floppy drive configuration.  Some machines	do not store any form of a
     configuration value in their CMOS.	 Use the flags value `0x1' to pretend
     a 1.44 MB floppy drive as the first unit, without asking the CMOS for it.

     The flags value `0x2' is reserved for PCMCIA floppy use, and should never
     be	set in a configuration file directly.  It is internally	handled	in the
     driver if the compilation option FDC_YE is	set, and defers	device prob-

     Normally, the device driver detects FDC chipsets that have	an internal
     FIFO, and enables the FIFO	on them.  There	is a slight chance that	this
     feature is	actually misdetected (seen on an IBM Thinkpad 755c), so	it can
     be	turned off using flags `0x4'.

     /dev/fd*			       floppy disk device nodes
     /dev/fd*._size in kB_	       floppy disk device nodes	where the
				       trailing	number indicates the floppy
     /sys/i386/conf/GENERIC	       sample generic kernel config file
     /sys/isa/fd.c		       floppy driver source

     fdformat(1), disktab(5)

FreeBSD	11.1			August 31, 1994			  FreeBSD 11.1


Want to link to this manual page? Use this URL:

home | help