LPC47S457-NC SMSC [SMSC Corporation], LPC47S457-NC Datasheet - Page 43

• Manufacturer Part Number: LPC47S457-NC
• Description: Advanced I/O with X-Bus Interface
• Manufacturer: SMSC [SMSC Corporation]

SMSC DS – LPC47S45x
DS0, DS1
SYMBOL
H/HDS
EFIFO
LOCK
MFM
EOT
GAP
HUT
GPL
DTL
HLT
EIS
MT
EC
Disk Drive Select
Special Sector
Size
Enable Count
Enable FIFO
Enable Implied
Seek
End of Track
Gap Length
Head Address
Head Load Time
Head Unload
Time
MFM/FM Mode
Selector
Multi-Track
Selector
NAME
Table 16 − Description of Command Symbols
By setting N to zero (00), DTL may be used to control the number of
bytes transferred in disk read/write commands. The sector size (N =
0) is set to 128. If the actual sector (on the diskette) is larger than
DTL, the remainder of the actual sector is read but is not passed to
the host during read commands; during write commands, the
remainder of the actual sector is written with all zero bytes. The CRC
check code is calculated with the actual sector. When N is not zero,
DTL has no meaning and should be set to FF HEX.
When this bit is "1" the "DTL" parameter of the Verify command
becomes SC (number of sectors per track).
This active low bit when a 0, enables the FIFO. A "1" disables the
FIFO (default).
When set, a seek operation will be performed before executing any
read or write command that requires the C parameter in the
command phase. A "0" disables the implied seek.
The Gap 3 size. (Gap 3 is the space between sectors excluding the
VCO synchronization field).
Selected head: 0 or 1 (disk side 0 or 1) as encoded in the sector ID
field.
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 the 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.
The final sector number of the current track.
Alters Gap 2 length when using Perpendicular Mode.
DATASHEET
DS1
0
0
Page 43 of 259
DS0
0
1
Drive 0
Drive 1
DESCRIPTION
DRIVE
Rev. 07/09/2001