28-1
Tandberg SLR Product Line SCSI Functional Specifications
28.
Test Unit Ready
28.1. Command Description
The TEST UNIT READY command provides a means to check if
the Drive is ready for a medium access command. If the
Drive would accept an appropriate medium access command
without returning CHECK CONDITION status, this command
will return GOOD status. See the section on Command Set
Summary for the list of Medium Access Commands.
The Drive will not disconnect when executing this
command.
28.2. Command Descriptor Block
BYTE
BIT 7
6
5
4
3
2
1
0
00
Operation Code
00h
01
Logical Unit Number (LUN)
RESERVED
02
RESERVED
03
RESERVED
04
RESERVED
05
Control Byte
Table 28-1: TEST UNIT READY Command Descriptor Block
28.3. Exception Handling
See section Error Conditions For All Commands.
In addition the TEST UNIT READY command will respond
with CHECK CONDITION status in the following situations:
Sense Key
AS/AQ
Description
Comments
ILLEGAL REQUEST
25h/00h
LOGICAL UNIT NOT
SUPPORTED
The LUN field of the IDENTIFY message or
in the CDB is not zero.
NOT READY
04h/01h
LOGICAL UNIT IS IN THE
PROCESS OF BECOMING
READY
The Drive is performing an auto-load or a
load operation. This response is produced
only when the BSYA bit of the Miscellaneous
Parameters Page is set to 1.
NOT READY
04h/02h
LOGICAL UNIT NOT READY,
INITIALIZING COMMAND
REQUIRED
The medium is inserted, but not loaded. The
Initiator should issue a LOAD command.
NOT READY
30h/03h
CLEANING CARTRIDGE
INSTALLED
The Drive can not perform media accesses
on a cleaning cartridge.
NOT READY
3Ah/00h
MEDIUM NOT PRESENT
There is no medium or the medium has been
ejected.
Table 28-2: TEST UNIT READY Response
