Start Stop Unit Command Descriptor Block-Data Format; Start Stop Unit Command-Field Descriptions - Maxtor ATLAS 10K III Product Manual

SCSI Description
The START STOP UNIT command enables or disables the logical unit for media
access operations. This command gives the initiator remote control over drive spin-
up and spin-down. The data format and field descriptions are shown in Table 5-205
and Table 5-206 respectively.
A jumper (or backplane connection) is used to select the spin-up mode. When
configured for remote control of spin-up (Option 3), the drive requires a START
STOP UNIT Command to spin up. See Chapter 3 for jumper-programming
instructions for your specific hard disk drive.
T a b l e 5 - 2 0 5 START STOP UNIT Command Descriptor Block-Data Format
$ K V
$ [ V G
0
1
2 - 3
4
5
T a b l e 5 - 2 0 6 START STOP UNIT Command-Field Descriptions
( K G N F
Immed
LoEj
Start
Power
Conditions
5-166 Maxtor Atlas 10K III
  
Power Conditions
Immediate. When 1, the drive returns GOOD status immediately after validat-
ing the Command Descriptor Block, but before the drive spins up.
When 0, the drive does not return GOOD status until after the drive has spun
up successfully and is ready for media access commands.
Load Eject. This value must be zero, because the disk drive contains non-re-
movable medium.
When Start is 1, the unit spins up (if it is not currently spinning) and is left
in a state where subsequent media access commands can succeed.
When the value is 0, the drive spins down. Subsequent media access com-
mands are rejected with CHECK CONDITION status and the proper sense da-
ta.
The Power Conditions field is not supported.
 
Operation Code (1Bh)
Reserved
Reserved
Reserved
Control
& G U E T K R V K Q P
  
Immed
LoEj Start