Product manual

3.4 Group 0 commands
3.4.1 Test Unit Ready command (00
H
)
The Test Unit Ready command verifies that the drive is ready; it is not a
request for a self-test. If the drive accepts an appropriate media access
command without encountering an error, it returns a good status.
Bit
Byte
7 6 5 4 3 2 1 0
0 0 0 0 0 0 0 0 0
1 LUN 0 0 0 0 0
2 0 0 0 0 0 0 0 0
3 0 0 0 0 0 0 0 0
4 0 0 0 0 0 0 0 0
5 0 0 0 0 0 0 Flag Link
3.4.2 Rezero Unit command (01
H
)
The Rezero Unit command requests that the drive set its logical block
address to zero and return the read/write heads to the track (or cylinder)
containing logical block 0.
This command is intended for systems that disable retries and the initiator
performs error recovery. It is longer than a seek to logical block address 0
and should be used if seek errors are encountered.
When used with a host adapter that supports disconnection, the drive
disconnects when this command is received.
Bit
Byte
7 6 5 4 3 2 1 0
0 0 0 0 0 0 0 0 1
1 LUN 0 0 0 0 0
2 0 0 0 0 0 0 0 0
3 0 0 0 0 0 0 0 0
4 0 0 0 0 0 0 0 0
5 0 0 0 0 0 0 Flag Link
34 ST3655 Family SCSI Drives Product Manual, Rev. A