NAME
fdc —
Amiga custom chip floppy disk
controller device
SYNOPSIS
fdc0 at mainbus0
fd* at fdc? unit ?
DESCRIPTION
The
fdc device driver provides support for the mainboard
floppy disk controller and floppy disk drives on Amiga systems.
The driver supports the following floppy diskette formats by using particular
partitions:
- 880KB 3.5-inch 11
sectors/track (``Amiga'') (a)
-
- 1.76MB 3.5-inch 22
sectors/track (``Amiga'') (a)
-
- 880KB 5.25-inch 11
sectors/track (``Amiga'') (a)
-
- 720KB 3.5-inch 9
sectors/track (``MS-DOS'') (b)
-
- 1.44MB 3.5-inch 18
sectors/track (``MS-DOS'') (b)
-
- 720KB 5.25-inch 9
sectors/track (``MS-DOS'') (b)
-
On systems equipped with floppy disk drives capable of using high-density floppy
diskettes, the driver automatically detects whether the inserted floppy
diskette is either a double-density or a high-density medium.
DIAGNOSTICS
- fdc: unable to allocate DMA
buffer
- The driver found the controller, but was unable to
allocate the amount of chip memory required for its DMA buffers.
SEE ALSO
fdformat(1),
amiga/autoconf(4)
BUGS
In order to detect a floppy disk drive's capability of using high-density media,
a high-density diskette has to be inserted for the duration of the
autoconfiguration phase of the drive.
The
fdc driver supports neither the
fdformat(1) facility nor
the
<sys/fdio.h> interface.