Hitachi HUS154530VLF400 User Manual

Page of 417
Hitachi Ultrastar 15K450 (FC-AL) Hard Disk Drive Specification
294 
19.59.1  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 247: Write Buffer Header
Byte
Bit
7
6
5
4
3
2
1
0
0-3
Reserved = 0