SAS Interface

ATTRIBUTE code is specified, a drive will treat the task as one with the SIMPLE task attribute.

Table 1.35 TASK ATTRIBUTE field

Code

Task attribute

 

 

000b

SIMPLE

 

 

001b

HEAD OF QUEUE

 

 

010b

ORDERED

 

 

011b

Reserved

 

 

100b

ACA (not supported)

 

 

101b-111b

Reserved

 

 

The ADDITIONAL CDB LENGTH field contains the length of the ADDITIONAL CDB field in dwords (four bytes). A drive expects a max 64-byte long COMMAND frame.

The CDB and ADDITIONAL CDB BYTES fields together contain the CDB to be interpreted by the addressed logical unit.

The contents of the CDB are defined in the SCSI command standards (e.g., SPC-3).

When a drive receives a COMMAND frame, the following items are checked:

HASHED DESTINATION SAS ADDRESS field

When this field contains a value different from the Hashed SAS address of the drive, the drive sends the ACK and CREDIT_BLOCKED primitives, and discards the COMMAND frame.

HASHED SOURCE SAS ADDRESS field

When this field contains a value different from the SOURCE SAS ADDRESS field of the OPEN frame, the drive sends the CREDIT_BLOCKED primitive, and discards the COMMAND frame.

82

C141-C013

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Fujitsu MBC2073RC, MBC2036RC, MBA3300RC, MBA3147RC, MBA3073RC Task Attribute field, Simple, Head of Queue, Ordered