TAPE UNIT SCSI COMMANDS M2488 PRODUCT GUIDE
4-138 CG00000-011503 REV. A April 1997
4-3.30 TEST UNIT READY command 00h
The TEST UNIT READY command provides a means to check if the logical unit is ready. This is not
a request for a self-test. If the logical unit would accept an appropriate medium-access command
without returning CHECK CONDITION status, this command returns a GOOD status.
4-3.30.1 TEST UNIT READY CDB Description
TEST UNIT READY is a six-byte command. The bytes are as shown below and described in
Table 4-127. Common fields are described in paragraph 4-3.1 on page 4-4.
4-3.30.2 TEST UNIT READY CHECK CONDITION Status
If a tape is not inserted or the drive is not ready, CHECK CONDITION status is returned with the
sense key set to NOT READY.
BITS
BYTES
7 6 5 4 3 2 1 0
0
0 0 0 0 0 0 0 0
1
LUN Reserved
2
Reserved
3
Reserved
4
Reserved
5
Reserved Flag Link
Note: Changeable fields in the CDB are shaded.
Table 4-127. TEST UNIT READY Field Description
BYTE BIT VALUE DESCRIPTION
0 0-7 00H Operation code.
