FDC(4) | Device Drivers Manual (x86) | FDC(4)

# NAME

`fdc` —
NEC 765 floppy disk controller driver

# SYNOPSIS

`fdc0 at isa? port 0x3f0 irq 6 drq 2`
`fdc* at acpi?`
`fdc* at pnpbios? index ?`
`fd* at fdc? drive ?`

# DESCRIPTION

The `fdc` driver provides support for the NEC 765 floppy disk controller and floppy disk drives, commonly found on IBM-PC compatible systems.

The driver supports the following floppy diskette formats by using particular partitions:

1.44MB 3.5-inch (b)
1.2MB 5.25-inch (c)
360KB 5.25-inch (1.2MB drive) (d)
360KB 5.25-inch (IBM-PC drive) (e)
720KB 3.5-inch (f)
720KB 5.25-inch (g)
360KB 3.5-inch (h)

Partition a selects the default format for the attached floppy drive, as determined by the BIOS configuration for the diskette drive.

# FORMATTING

The driver supports floppy disk formatting using the interfaces in `<sys/fdio.h>`:

`FDIOCGETFORMAT` struct fdformat_parms
  Fetch current formatting parameters. This gets the default parameters for the open device if no parameters have been set during the session.
`FDIOCSETFORMAT` struct fdformat_parms
  Set formatting parameters. The driver saves this state and it persists while the device is open.
`FDIOCFORMAT_TRACK` struct fdformat_cmd
  Format a track on the medium. If this call returns `EINVAL`, the track formatting parameters were out of range for the medium. If it returns `EIO`, there was a medium error while formatting the track.
`FDIOCSETOPTS` int
  Set driver options which persist until the device is closed. The options should be the logical OR of the desired values below:
  `FDOPT_NORETRY`
    Do not retry operations on failure
  `FDOPT_SILENT`
    Do not print error messages to the console
`FDIOCGETOPTS` int
  Fetch drive options.

A typical use of the formatting facilities would be to open the device, call `FDIOCGETFORMAT` to fetch the current format parameters, perhaps change a parameter or two, display the formatting details to the user, and then call `FDIOCSETFORMAT` followed by a series of calls to `FDIOCFORMAT_TRACK`.

# SEE ALSO

fdformat(1), acpi(4), isa(4), pnpbios(4)

# HISTORY

The `fdc` formatting support appeared in NetBSD 1.3.

September 23, 2011 | NetBSD 9.4