LPC47B37X View Datasheet(PDF) - SMSC -> Microchip
Part Name
Description
MFG CO.
LPC47B37X
SMSC -> Microchip
'LPC47B37X' PDF : 254 Pages View PDF
Read Deleted Data
This command is the same as the Read Data command, only it operates on sectors that contain a Deleted
Data Address Mark at the beginning of a Data Field.
Table 21 describes the effect of the SK bit on the Read Deleted Data command execution and results.
Except where noted in Table 21, the C or R value of the sector address is automatically incremented (see
Table 22).
Table 21 - Skip Bit vs. Read Deleted Data Command
DATA ADDRESS
SK BIT
MARK TYPE
RESULTS
VALUE ENCOUNTERED
SECTOR CM BIT OF DESCRIPTION OF
READ? ST2 SET?
RESULTS
0 Normal Data
Yes
Yes
Address not
incremented. Next
sector not
searched for.
0 Deleted Data
Yes
No
Normal
termination.
1 Normal Data
No
Yes
Normal
termination.
Sector not read
("skipped").
1 Deleted Data
Yes
No
Normal
termination.
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.
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