Table 5-5 contains a description of the CDB control field.

Table 5-5Command Descriptor Block Control Field-Field Descriptions

Field

Description

 

 

Vendor Specific Bits

These bits must be 0.

 

 

NACA

Normal Auto-Contingent Allegiance - This bit must be zero to indicate that

 

SCSI-2 Contingent Allegiance rules apply.

 

 

Link Bit

A Link bit set to one signals that the initiator requests continuation of a task

 

(I/O Process) across two or more SCSI commands. If the Link bit is one and the

 

flag bit is zero, and the command completes successfully, the drive will continue

 

the task and return a status of INTERMEDIATE and a service response of

 

Linked Command Complete.

 

If the Link bit and the Flag bit of the Control word are both set to one, and the

 

drive completes a command with a status of INTERMEDIATE, the drive will

 

return a service response of Linked Command Complete (with Flag). Refer to

 

Section 5.4 for Linked Commands description.

 

 

Flag Bit

The Flag bit is used in conjunction with the Link Bit to notify the initiator in

 

an expedient manner that a command has been completed. Aflag bit set to 1 is

 

valid only when the Link Bit is set to 1.

 

 

5-6 Maxtor Atlas 10K V

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