Quantum 10K II - Manual (Page 278)

SCSI Description
Quantum Atlas 10K II Ultra160/m SCSI Hard Disk Drives 5–211
5.44 TEST UNIT READY Command (00h)
The TEST UNIT READY command returns GOOD status if the drive is ready to
receive medium access commands (that is, READ, WRITE, VERIFY, etc.). If the
drive is not ready to receive medium access commands, it returns CHECK
CONDITION status with the appropriate sense keys and qualifiers.
Bit
Byte
7 6 5 4 3 2 1 0
0 Operation Code (00h)
1 - 4 Reserved
5 Control
Figure 5–104 TEST UNIT READY Command Descriptor Block — Data Format