
65
Table 22 – Verify Command Result Phase Table
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
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
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 nINDEX 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 nINDEX pin again and it terminates the command.
Table 24 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.