TEST UNIT READY
7. ATAPI Packet Command Specification
SONY AIT-1 Turbo drive SDX-470V series Ver.1.0
7-75
7.22. TEST UNIT READY 00h
Bit
Byte
7 6 5 4 3 2 1 0
0
Operation Code (00h)
1
Reserved
2
Reserved
3
Reserved
4
Reserved
5
Reserved
6
Reserved
7
Reserved
8
Reserved
9
Reserved
10
Reserved
11
Reserved
The TEST UNIT READY command provides a means to check if the Device is ready. This is not a request for a
self-test. If the Device would accept an appropriate medium-access command without returning “Check Condition”
status, this command shall return a “Good” status. If the Device cannot become operational or is in a state such
that Host action is required to make the unit ready, the Device shall return “Check Condition” status with a Sense
Key of NOT READY.
The TEST UNIT READY command is useful in that it allows the Host to poll a Device until it is ready without the
need to allocate space for returned data. It is especially useful to check cartridge status. Devices are expected to
respond promptly to indicate the current status of the Device.
If a prior command is running upon receipt of this command such as an erase or rewind, the device shall report
check condition with sense key 2 (NOT READY) and ASC/ASQ=04h/01h.
