FDC37M81x SMSC Corporation, FDC37M81x Datasheet - Page 39

• Manufacturer Part Number: FDC37M81x
• Description: PC98/99 Compliant Enhanced Super I/O Controller
• Manufacturer: SMSC Corporation

HLT
HUT
LOCK
MFM
MT
N
NCN
ND
OW
SYMBOL
Head Load
Time
Head Unload
Time
MFM/FM Mode
Selector
Multi-Track
Selector
Sector Size
Code
New Cylinder
Number
Non-DMA
Mode Flag
Overwrite
NAME
Table 17 - Description of Command Symbols
The bits D0-D3 of the Perpendicular Mode Command can only be
The time interval that FDC waits after loading the head and before
initializing a read or write operation. Refer to the Specify command for
actual delays.
The time interval from the end of the execution phase (of a read or write
command) until the head is unloaded. Refer to the Specify command
for actual delays.
Lock defines whether EFIFO, FIFOTHR, and PRETRK parameters of
the CONFIGURE COMMAND can be reset to their default values by a
"software Reset". (A reset caused by writing to the appropriate bits of
either tha DSR or DOR)
A one selects the double density (MFM) mode. A zero selects single
density (FM) mode.
When set, this flag selects the multi-track operating mode. In this
mode, the FDC treats a complete cylinder under head 0 and 1 as a
single track. The FDC operates as this expanded track started at the
first sector under head 0 and ended at the last sector under head 1.
With this flag set, a multitrack read or write operation will automatically
continue to the first sector under head 1 when the FDC finishes
operating on the last sector under head 0.
This specifies the number of bytes in a sector. If this parameter is "00",
then the sector size is 128 bytes. The number of bytes transferred is
determined by the DTL parameter. Otherwise the sector size is (2
raised to the "N'th" power) times 128. All values up to "07" hex are
allowable. "07"h would equal a sector size of 16k. It is the user's
responsibility to not select combinations that are not possible with the
drive.
The desired cylinder number.
When set to 1, indicates that the FDC is to operate in the non-DMA
mode. In this mode, the host is interrupted for each data transfer.
When set to 0, the FDC operates in DMA mode, interfacing to a DMA
controller by means of the DRQ and nDACK signals.
modified if OW is set to 1. OW id defined in the Lock command.
00
01
02
03
07
…
N
Sector Size
128 Bytes
256 Bytes
512 Bytes
1024 Bytes
16,384 Bytes
39
DESCRIPTION