TABLE 28 - VERIFY COMMAND RESULT PHASE
MT
EC
SC/EOT VALUE
TERMINATION RESULT
0
0
SC = DTL
Success Termination
EOT # Sectors Per Side
Result Phase Valid
0
0
SC = DTL
Unsuccessful Termination
EOT > # Sectors Per Side
Result Phase Invalid
0
1
SC # Sectors Remaining AND
Successful Termination
EOT # Sectors Per Side
Result Phase Valid
0
1
SC > # Sectors Remaining OR
Unsuccessful Termination
EOT > # Sectors Per Side
Result Phase Invalid
1
0
SC = DTL
Successful Termination
EOT # Sectors Per Side
Result Phase Valid
1
0
SC = DTL
Unsuccessful Termination
EOT > # Sectors Per Side
Result Phase Invalid
1
1
SC # Sectors Remaining AND
Successful Termination
EOT # Sectors Per Side
Result Phase Valid
1
1
SC > # Sectors Remaining OR
Unsuccessful Termination
EOT > # Sectors Per Side
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.
Format A Track
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
C, H, R, and N (cylinder, head, sector number and
sector size respectively).
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.
Table 25 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.
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