
59
TABLE 28 - VERIFY COMMAND RESULT PHASE
SC/EOT VALUE
SC = DTL
EOT # Sectors Per Side
SC = DTL
EOT > # Sectors Per Side
SC # Sectors Remaining AND
EOT # Sectors Per Side
SC > # Sectors Remaining OR
EOT > # Sectors Per Side
SC = DTL
EOT # Sectors Per Side
SC = DTL
EOT > # Sectors Per Side
SC # Sectors Remaining AND
EOT # Sectors Per Side
SC > # Sectors Remaining OR
EOT > # Sectors Per Side
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
MT
0
EC
0
TERMINATION RESULT
Success Termination
Result Phase Valid
Unsuccessful Termination
Result Phase Invalid
Successful Termination
Result Phase Valid
Unsuccessful Termination
Result Phase Invalid
Successful Termination
Result Phase Valid
Unsuccessful Termination
Result Phase Invalid
Successful Termination
Result Phase Valid
Unsuccessful Termination
Result Phase Invalid
0
0
0
1
0
1
1
0
1
0
1
1
1
1
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
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 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.
be
formatted
with