Hitachi HUS154530VLF400 User Manual

Hitachi Ultrastar 15K450 (FC-AL) Hard Disk Drive Specification

320   

There are certain errors or conditions which may impair the ability of the drive to function normally. Rather than fail hard the 
drive is designed to be as responsive as possible. Also, in most cases, some action on the part of the initiator may be used to 
restore normal operation. This mode of limited operation is called Degraded Mode.

There are 3 conditions in the Degraded Mode:

•

Spindle Motor Degrade which is caused by one of the following conditions:

-  Spindle Motor is not started by the option jumper setting (Disable Auto Spin Up)

-  Spindle Motor is delayed from spinning up by the option jumper setting (Auto Start Delay)

-  Spindle Motor was started (by POR or Unit Start command) and the Target is under Self Configuration.

-  Spindle Motor Failed to start.

-  Spindle Motor was stopped by Unit Stop command after the Target successfully completed the Self Configuration.

•

Self Configuration Failure Degraded which is caused by one of the following conditions:

-  RAM Code, Configuration Sector Read Failure

-  RAM Code, Configuration Sector Revision Mismatch

•

Format Command Failure Degraded. This condition is caused when Format Unit command failed or was interrupted 

abnormally (Mode Page 0, byte 5, bit 4 FDD controls Format Degraded mode)