57 write (6) command, Write (6) command – Seagate Fibre Channel Interface User Manual

Page 336

Advertising
background image

322

Fibre Channel Interface Manual, Rev. D

12.57

Write (6) command

The Write (6) command requests that the disc drive write the data transferred by the initiator to the medium
(discs).

Field definitions (listed alphabetically)

Control
See Control Bytes in Section 11.2.1.6.

Logical Block Address
The logical block at which the write operation begins.

Transfer Length
The number of contiguous logical blocks of data to be transferred. Any value other than 0 indicates the number of logical
blocks that are transferred.
0

Transfer 256 logical blocks

The disc drive closes the loop when any internal error recovery procedure is required, or if the disc drive’s
internal data buffer is full. After the disc closes, the initiator must re-arbitrate to send the remaining data.

The initiator must send requested write data to the drive until the drive sends Completion status or until the ini-
tiator resets/aborts the command or clears the queue. (The initiator may close and re-arbitrate at any time
while executing this command).

Sense Data is valid after this command is executed and Completion status is sent (refer to the Read (6) Com-
mand description in Section 12.21).

If the RCD bit is set to zero on the Caching Mode page 08h (cache is enabled), the data that is written by this
command remains in the cache buffer, if no write errors are encountered. This allows a Read command to
access the same data from the cache buffer instead of accessing the media, if the same LBA is requested by
the Read command.

This command is terminated with a Reservation Conflict status and no data is written if any reservation access
conflict (see Section 12.39) exists.

Table 220: Write (6) command (0Ah)

Bit

Byte

7

6

5

4

3

2

1

0

0

0

0

0

0

1

0

1

0

1

0

0

0

(MSB)

Reserved

Logical Block Address

2

3

(LSB)

4

Transfer Length

5

Control

0Ah

Table

number

220

220

220

Advertising
This manual is related to the following products: