command can also be terminated by setting the
EC bit to "0" and the EOT value equal to the final
sector to be checked. If EC is set to "0", DTL/SC
should be programmed to 0FFH. Refer to Table
27 and Table 28 for information concerning the
values of MT and EC versus SC and EOT value.
Definitions:
# Sectors Per Side = Number of formatted sectors
per each side of the disk.
# Sectors Remaining = Number of formatted
sectors left which can be read, including side 1 of
the disk if MT is set to "1".
TABLE 28 - VERIFY COMMAND RESULT PHASE
SC/EOT VALUE TERMINATION RESULT
Success Termination
MT
EC
0
0
SC = DTL
Result Phase Valid
EOT ≤ # Sectors Per Side
0
0
0
1
1
1
1
0
1
1
0
0
1
1
SC = DTL
EOT > # Sectors Per Side
Unsuccessful Termination
Result Phase Invalid
Successful Termination
Result Phase Valid
SC ≤ # Sectors Remaining AND
EOT ≤ # Sectors Per Side
SC > # Sectors Remaining OR
EOT > # Sectors Per Side
Unsuccessful Termination
Result Phase Invalid
SC = DTL
EOT ≤ # Sectors Per Side
Successful Termination
Result Phase Valid
SC = DTL
EOT > # Sectors Per Side
Unsuccessful Termination
Result Phase Invalid
Successful Termination
Result Phase Valid
SC ≤ # Sectors Remaining AND
EOT ≤ # Sectors Per Side
SC > # Sectors Remaining OR
EOT > # Sectors Per Side
Unsuccessful Termination
Result Phase Invalid
Note: If MT is set to "1" and the SC value is greater than the number of remaining formatted sectors on
Side 0, verifying will continue on Side 1 of the disk.
C, H, R, and N (cylinder, head, sector number and
sector size respectively).
Format A Track
After formatting each sector, the host must send
new values for C, H, R and N to the FDC for the
next sector on the track. The R value (sector
number) is the only value that must be changed by
the host after each sector is formatted. This
allows the disk to be formatted with nonsequential
sector addresses (interleaving). This incrementing
and formatting continues for the whole track until
the FDC encounters a pulse on the IDX pin again
and it terminates the command.
The Format command allows an entire track to be
formatted. After a pulse from the IDX pin is
detected, the FDC starts writing data on the disk
including gaps, address marks, ID fields, and data
fields per the IBM System 34 or 3740 format (MFM
or FM respectively). The particular values that will
be written to the gap and data field are controlled
by the values programmed into N, SC, GPL, and D
which are specified by the host during the
command phase. The data field of the sector is
filled with the data byte specified by D. The ID field
for each sector is supplied by the host; that is, four
data bytes per sector are needed by the FDC for
TABLE 29 contains typical values for gap fields
which are dependent upon the size of the sector
and the number of sectors on each track. Actual
values can vary due to drive electronics.
61
SMSC [ SMSC CORPORATION ]
