Maxtor ATLAS 10K III - Manual (Page 235)

SCSI Description
Maxtor Atlas 10K III 5-171
 94+6'  %QOOCPF #J
The WRITE (10) command requests that the drive write initiator-supplied data to the
medium. The data format and field descriptions are shown in Table 5-214 and Table
5-215 respectively.
Table 5-214 WRITE (10) Command Descriptor Block-Data Format
Table 5-215 WRITE (10) Command-Field Descriptions
$KV
$[VG
       
0 Operation Code (2Ah)
1 Reserved DPO FUA Reserved RelAdr
2 - 5 Logical Block Address
6 Reserved
7 - 8 Transfer Length
9 Control
(KGNF &GUETKRVKQP
DPO
Disable Page Out. When the value of the field is 1, the drive tells the control-
ler to bypass cache as much as possible. The buffers used for the WRITE
data are given a low priority. This bit may be useful if the host CPU is per-
forming a background copy operation and does not want to wipe out the
drive's cache.
When DPO is 0, the drive tells the controller to cache this WRITE data in a
normal manner.
NOTE: The drive normally assigns a low priority to write caching. Therefore,
the DPO bit in a WRITE command is ignored.
FUA
Force Unit Access. When 1, the data must be written on the medium before
GOOD status is returned. When 0, GOOD status may be returned after the
data is fetched from the initiator and before it is written to the medium. If
the WCE (Write Cache Enable) bit on the MODE SELECT command Caching
Page is clear, the FUA bit is ignored and behaves as if it were always set (that
is, if WCE = 0, the controller forces FUA = 1).
Logical Block
Address
The address of the first logical block where the Write operation will occur.
RelAdr
Relative Address. This drive does not support this feature; the field must be
0.
Transfer
Length
The number of contiguous logical blocks of data to write. The drive returns
CHECK CONDITION status with the correct sense data if the specified trans-
fer would cause the write operation to extend beyond the Logical Block Ad-
dress space.