Write (0A) - Fujitsu MAX3073NC - SCSI,80, Dell DC961,Hard Drive Scsi Logical Interface Specifications

3.2.3

WRITE (0A)

Bit
Byte
0
1
2
3
4
5
This command transfers the number of blocks of data specified in the "Transfer block count" field from
the INIT and writes them in continuous logical data blocks with the logical data block on the disk media
specified in the "Logical block address" field in the CDB as the top.
The transfer block count can be specified up to a maximum of 256 logical data blocks. When zero is
specified in the "Transfer block count" field in byte 4 of the CDB, it specifies transfer of 256 logical data
blocks and when a value other than zero is specified, it specifies the number of logical data blocks that
should be transferred.
When transfer of multiple data blocks is instructed by this command, when the data blocks which are to
be processed come to a track boundary, cylinder boundary or zone boundary, a head switch or cylinder
switch is executed automatically and writing of the specified number of blocks is performed.
When the specifications in the "Logical block address" field and "Transfer block count" field in the CDB
exceed the maximum logical block address in the IDD, that command is terminated with a CHECK
CONDITION status (ILLEGAL REQUEST [=5] / Logical block address out of range [=21-00]) and
writing of data to the disk media is not executed.
The IDD does not perform data transfer immediately after receiving the CDB, but after performing
automatic disconnect processing once, it executes pre-fetching of data. If disconnect processing is
permitted, the IDD either completes transfer of all the data specified in the command or, at the point
when the empty space in the data buffer runs out, disconnect processing is executed. Positioning of the
specified data blocks is performed in parallel with this data transfer, and writing of data from the data
buffer to the disk media is executed immediately after positioning is completed. See Section 2.1 "Data
Buffer" for details of data buffer operation and control of the timing for starting reconnection processing
by the MODE SELECT parameter (buffer empty ratio).
If the write cache function is enabled, the IDD reports a status at the point when reception of all the data
transferred from the INIT is completed. If an error occurs while data are being written to the disk media,
a CHECK CONDITION status is reported for the command to be executed next. If the write cache
function is disabled, a status is reported after writing to the disk media of all the data transferred from the
INIT is completed, then execution of the command is terminated.
C141-C010
7 6 5
LUN
Logical Block Address
Logical Block Address (LSB)
Transfer Block Count
0 0 0
3.2 Data Access Commands
4 3 2
X'0A'
Logical Block Address (MSB)
0 0 0
1 0
0 Link
3-73