6 control byte, Control byte, See section 11.2.1.6 – Seagate Fibre Channel Interface User Manual

Page 147

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Fibre Channel Interface Manual, Rev. D

133

The Transfer Length field of the commands used to return sense data (e.g., Request Sense, Inquiry, Mode
Sense, etc.) to an initiator is called the Allocation Length field. The Allocation Length field specifies the number
of bytes that the initiator has allocated for returned data. The disc drive terminates the data in the FCP DATA
sequence when Allocation Length bytes have been transferred or when all available data have been trans-
ferred to the initiator, whichever is less.

11.2.1.6

Control byte

Normally all zeros unless the extended features of ACA or Link commands are being used.

Field definitions (listed alphabetically)

Flag
Drives supported by this manual do not use this bit.

Link
This bit is set to one (1) to indicate that the initiator desires an automatic link to the next command upon successful comple-
tion of the current command. If the link bit is one (1), upon successful termination of the command, the drive returns Inter-
mediate status in the FCP RSP frame.

Note.

The OX_ID must be the same for all linked commands because it is considered the same exchange.

NACA (Normal Auto Contingent Allegiance)
1

Enables ACA handling rules for the command. If a Check Condition occurs during the processing of the command,
an ACA condition is entered.

0

Disables ACA handling rules for the command.

Table 79:

Control byte

Bit
Byte

7

6

5

4

3

2

1

0

LAST

0

0

0

0

0

NACA

Flag

Link

Reserved

Table

number

79

79

79

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