LPC47M172_07 Datasheet, PDF (64/226 Pages) SMSC Corporation – Advanced I/O Controller with Motherboard GLUE Logic

Advanced I/O Controller with Motherboard GLUE Logic
Datasheet
Table 6.21 - Skip Bit vs. Read Deleted Data Command
SK BIT
VALUE
0
0
1
1
DATA ADDRESS
MARK TYPE
ENCOUNTERED
Normal Data
Deleted Data
Normal Data
Deleted Data
SECTOR
READ?
Yes
Yes
No
Yes
RESULTS
CM BIT OF
ST2 SET?
Yes
No
Yes
No
DESCRIPTION
OF RESULTS
Address not
incremented. Next
sector not
searched for.
Normal
termination.
Normal
termination.
Sector not read
(“skipped”).
Normal
termination.
6.13 Read A Track
This command is similar to the Read Data command except that the entire data field is read continuously
from each of the sectors of a track. Immediately after encountering a pulse on the nINDEX pin, the FDC
starts to read all data fields on the track as continuous blocks of data without regard to logical sector
numbers. If the FDC finds an error in the ID or DATA CRC check bytes, it continues to read data from the
track and sets the appropriate error bits at the end of the command. The FDC compares the ID
information read from each sector with the specified value in the command and sets the ND flag of Status
Register 1 to a “1” if there no comparison. Multi-track or skip operations are not allowed with this
command. The MT and SK bits (bits D7 and D5 of the first command byte respectively) should always be
set to “0”.
This command terminates when the EOT specified number of sectors has not been read. If the FDC does
not find an ID Address Mark on the diskette after the second occurrence of a pulse on the nINDEX pin,
then it sets the IC code in Status Register 0 to “01” (abnormal termination), sets the MA bit in Status
Register 1 to “1”, and terminates the command.
Table 6.22 - Result Phase Table
FINAL SECTOR
MT
HEAD TRANSFERRED TO
HOST
ID INFORMATION AT RESULT PHASE
C
H
R
N
0
0
Less than EOT
NC
NC
R+1
NC
Equal to EOT
C+1
NC
01
NC
1
Less than EOT
NC
NC
R+1
NC
Equal to EOT
C+1
NC
01
NC
1
0
Less than EOT
NC
NC
R+1
NC
Equal to EOT
NC
LSB
01
NC
1
Less than EOT
NC
NC
R+1
NC
Equal to EOT
C+1
LSB
01
NC
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.
SMSC/Non-SMSC Register Sets (Rev. 01-11-07)
Page 64
DATASHEET
SMSC LPC47M172