1.\" 2.\" Copyright (c) 1994 Wilko Bulte 3.\" All rights reserved. 4.\" 5.\" Redistribution and use in source and binary forms, with or without 6.\" modification, are permitted provided that the following conditions 7.\" are met: 8.\" 1. Redistributions of source code must retain the above copyright 9.\" notice, this list of conditions and the following disclaimer. 10.\" 2. Redistributions in binary form must reproduce the above copyright 11.\" notice, this list of conditions and the following disclaimer in the 12.\" documentation and/or other materials provided with the distribution. 13.\" 3. The name of the author may not be used to endorse or promote products 14.\" derived from this software withough specific prior written permission 15.\" 16.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 17.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 18.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 19.\" IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 20.\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 21.\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 22.\" DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 23.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 24.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 25.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 26.\" 27.\" $FreeBSD$ 28.\" 29.Dd August 31, 1994 30.Dt FDC 4 31.Os FreeBSD 32.Sh NAME 33.Nm fdc 34.Nd PC architecture floppy disk controller driver 35.Sh SYNOPSIS 36.Cd "device fdc0 at isa? port IO_FD1 flags 0x1 irq 6 drq 2" 37.Cd device fd0 at fdc0 drive 0 38.Cd device fd1 at fdc0 drive 1 39.Sh DESCRIPTION 40This driver provides access to floppy disk drives. 41In /dev for each floppy device a number of minor devices are present. 42The 43/dev/fd* devices with trailing alphabetic characters are used to indicate 44.Sq partitions 45on the floppy disk. 46The /dev/fd*.<number> are devices that 47indicate the size of the floppy disk (so: 720kB, 1440kB etc). The latter 48are used for formatting disks using fdformat or for accessing different 49density disks in multidensity drive. 50Example: 720kB disk in a 1.44Mb drive. 51.Pp 52Normally, the driver will ask the system's CMOS memory to obtain the 53floppy drive configuration. Some machines do not store any form of a 54configuration value in their CMOS. Use the flags value 55.Ql 0x1 56to pretend a 1.44 MB floppy drive as the first unit, without asking the 57CMOS for it. 58.Pp 59Normally, the device driver detects FDC chipsets that have an internal 60FIFO, and enables the FIFO on them. There is a slight chance that this 61feature is actually misdetected (seen on an IBM Thinkpad 755c), so it 62can be turned off using flags 63.Ql 0x4 . 64.Sh FILES 65.Bl -tag -width Pa -compact 66.It Pa /dev/fd* 67floppy disk device nodes 68.It Pa /dev/fd*. Ns Ar "<size in kB>" 69floppy disk device nodes where the trailing number indicates the floppy 70capacity 71.It Pa /sys/i386/conf/GENERIC 72sample generic kernel config file 73.It Pa /sys/isa/fd.c 74floppy driver source 75.El 76.Sh SEE ALSO 77.Xr fdformat 1 , 78.Xr disktab 5 79