Hitachi HUS154530VLF400 User Manual

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Hitachi Ultrastar 15K450 (FC-AL) Hard Disk Drive Specification
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18.2.4.1  FCP_STATUS
The FCP_STATUS field is normally zero upon successful completion of an IOP. 
Table 95: FCP_STATUS field
The Flags field contains the following: 
 
Bits 7-4 - Reserved 
 
Bit 3 - FCP_RESID_UNDER 
 
When set to one, this flag indicates that the FCP_RESID field is valid and contains a count of the number of bytes 
that were expected but not received. 
 
Bit 2 - FCP_RESID_OVER 
 
When set to one, this flag indicates that the FCP_RESID field is valid and contains a count of the number of bytes 
that could not be transferred because FCP_DL was not sufficient. 
 
Bit 1 - FCP_SNS_LEN_VALID 
 
When set to one, this flag indicates that the FCP_SNS_LEN field is valid and contains a count of the number of bytes 
in the FCP_SNS_INFO field. 
 
Bit 0 - FCP_RSP_LEN_VALID 
 
When set to one, this flag indicates that the FCP_RSP_LEN field is valid and contains a count of the number of bytes 
in the FCP_RSP_INFO field. 
The SCSI Status byte field is defined in 20.0, “SCSI Status Byte”, on page 307. 
18.2.4.2  FCP_RESID
This field contains a count of the number of residual data bytes that were not transferred for this SCSI command. 
18.2.4.3  FCP_SNS_LEN
This field contains a count of the number of valid bytes in the FCP_SNS_INFO field. 
18.2.4.4  FCP_RSP_LEN
If the FCP_RSP_LEN_VALID flag in the FCP_STATUS field is set to 1b, this field contains a count of the number of valid 
bytes in the FCP_RSP_INFO field. 
Valid values are 0, 4, and 8. 
Byte Description 
Size 
(Bytes) 
0-1 
Reserved 2 
Flags 1 
SCSI Status byte