User Manual

SCSI Commands Reference Manual, Rev. J 230
www.seagate.com Direct Access Block commands (SPC-5 and SBC-4)
3.53 TEST UNIT READY command
The TEST UNIT READY command (see table 202) provides a means to check if the logical unit is ready. This is not a request for a
self-test. If the logical unit is able to accept an appropriate medium-access command without returning CHECK CONDITION
status, this command shall return a GOOD status. If the logical unit is unable to become operational or is in a state such that an
application client action (e.g., START UNIT command) is required to make the logical unit ready, the command shall be
terminated with CHECK CONDITION status, with the sense key set to NOT READY.
Table 203 defines the suggested GOOD and CHECK CONDITION status responses to the TEST UNIT READY command. Other
conditions, including deferred errors, may result in other responses (e.g., BUSY or RESERVATION CONFLICT status).
Table 202 TEST UNIT READY command
Bit
Byte
7 6 5 4 3 2 1 0
0
OPERATION CODE (00h)
1
Reserved
. . .
4
5
CONTROL
Table 203 Preferred TEST UNIT READY responses
Status Sense Key Additional Sense Code
GOOD not applicable
not applicable
CHECK CONDITION ILLEGAL REQUEST
LOGICAL UNIT NOT SUPPORTED
CHECK CONDITION NOT READY
LOGICAL UNIT DOES NOT RESPOND TO SELECTION
CHECK CONDITION NOT READY
MEDIUM NOT PRESENT
CHECK CONDITION NOT READY
LOGICAL UNIT NOT READY, CAUSE NOT REPORTABLE
CHECK CONDITION NOT READY
LOGICAL UNIT IS IN PROCESS OF BECOMING READY
CHECK CONDITION NOT READY
LOGICAL UNIT NOT READY, INITIALIZING COMMAND REQUIRED
CHECK CONDITION NOT READY
LOGICAL UNIT NOT READY, MANUAL INTERVENTION REQUIRED
CHECK CONDITION NOT READY
LOGICAL UNIT NOT READY, FORMAT IN PROGRESS