Combined Header And Data (Mode 00000B); Write Data (Mode 00010B); Table 163. Write Buffer Header - Hitachi HUS151473VL3800 - Ultrastar 73.4 GB Hard Drive Specifications

17.45.1 Combined Header And Data (Mode 00000b)

In this mode, the data to be transferred is preceded by a four-byte header.
Buffer ID must be zero. If another value is specified, no download function is performed and the command is terminated with
Check Condition status. And the drive shall set the sense key to Illegal Request and additional sense code to Illegal Field in
CDB.
Buffer Offset must be zero. If another value is specified, no download function is performed and the command is terminated
with Check Condition status. And the drive shall set the sense key to Illegal Request and additional sense code to Illegal Field
in CDB.
Parameter List Length specifies the number of bytes that shall be transferred during the DATA OUT phase. This number
includes four bytes of header, so the data length to be stored in the drive buffer is transfer length minus four. If the length
exceeds the buffer size, the command is terminated with Check Condition status. And the drive shall set sense key to Illegal
Request and additional sense code to Illegal Field in CDB. A Parameter List Length of less than four (size of header) indicates
no data is transferred.
The 4-byte header consists of all reserved bytes.
Table 163: Write Buffer Header
Byte
7
0-3

17.45.2 Write Data (Mode 00010b)

In this mode, the DATA OUT phase contains buffer data.
Buffer ID must be zero. If another value is specified, no download function is performed and the command is terminated with
Check Condition status. And the drive shall set the sense key to Illegal Request and additional sense code to Illegal Field In
CDB.
Buffer Offset specifies the offset of the memory space specified by the Buffer ID. The initiator should conform to the offset
boundary requirements returned in the READ BUFFER descriptor. If the value exceeds the buffer specified, the command is
terminated with Check Condition status. And the drive shall set the sense key to Illegal Request and additional sense code to
Illegal Field In CDB.
Parameter List Length specifies the Parameter List Length. It must be
• less than the capacity of the buffer size after adding the Buffer Offset value and
• on a sector boundary
A Parameter List Length of zero indicates no data is to be transferred and command status is returned.
If an invalid value is specified, the command is terminated with Check Condition status. And the drive shall set the sense key
to Illegal Request and additional sense code to Illegal Field In CDB.
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6 5 4
Reserved = 0
Hitachi Ultrastar 15K147 SCSI Hard Disk Drive Specification
Bit
3 2
201
1 0