FDC37B77X SMSC Corporation, FDC37B77X Datasheet - Page 55

• Manufacturer Part Number: FDC37B77X
• Description: ENHANCED SUPER I/O CONTROLLER WITH WAKE UP FEATURES
• Manufacturer: SMSC Corporation

NC: No Change, the same value as the one at the beginning of command execution.
LSB: Least Significant Bit, the LSB of H is complemented.
Write Data
After the Write Data command has been issued,
the FDC loads the head (if it is in the unloaded
state), waits the specified head load time if
unloaded (defined in the Specify command),
and begins reading ID fields. When the sector
address read from the diskette matches the
sector address specified in the command, the
FDC reads the data from the host via the FIFO
and writes it to the sector's data field.
After writing data into the current sector, the
FDC computes the CRC value and writes it into
the CRC field at the end of the sector transfer.
The Sector Number stored in "R" is incremented
by one, and the FDC continues writing to the
next data field. The FDC continues this "Multi-
Sector Write Operation". Upon receipt of a
terminal count signal or if a FIFO over/under run
occurs while a data field is being written, then
the remainder of the data field is filled with
zeros.
sector and checks the CRC bytes. If it detects a
CRC error in one of the ID fields, it sets the IC
code in Status Register 0 to "01" (abnormal
MT
0
1
The FDC reads the ID field of each
HEAD
0
1
0
1
TRANSFERRED TO
FINAL SECTOR
Less than EOT
Less than EOT
Less than EOT
Less than EOT
Equal to EOT
Equal to EOT
Equal to EOT
Equal to EOT
HOST
Table 23 - Result Phase Table
55
C + 1
C + 1
C + 1
NC
NC
NC
NC
NC
termination), sets the DE bit of Status Register 1
to "1", and terminates the Write Data command.
The Write Data command operates in much the
same manner as the Read Data command. The
following items are the same. Please refer to the
Read Data Command for details:
Write Deleted Data
This command is almost the same as the Write
Data command except that a Deleted Data
Address Mark is written at the beginning of the
Data Field instead of the normal Data Address
Mark. This command is typically used to mark
a bad sector containing an error on the floppy
disk.
C
ID INFORMATION AT RESULT PHASE
Transfer Capacity
EN (End of Cylinder) bit
ND (No Data) bit
Head Load, Unload Time Interval
ID information when the host terminates the
command
Definition of DTL when N = 0 and when N
does not = 0
LSB
LSB
NC
NC
NC
NC
NC
NC
H
R + 1
R + 1
R + 1
R + 1
01
01
01
01
R
NC
NC
NC
NC
NC
NC
NC
NC
N