Quantum ProDrive 40S - EXTENDED SENSE Formal

Section 5
SCSI Programming Guidelines
If the allocation length prevents all available sense data from being sent to the initiator, the initiator
may not use a subsequent REQUEST SENSE command to recover the remaining portion.
The
ProDrive uses the extended format for sense data. (See Table 5-11.)
5.11.3.2
Extended Sense Format
TABLE 5-11 Extended Sense Format
Bit
7
6
I
s
I
4
I
3
I
1
I
1
I
0
Byte
0
VALID
ERROR CLASS AND CODE = 7~
1
SEGMENT NUMBER = 0
2 FM=O
EOM=1 I
RJ=O
I
R=O
I
SENSE KEY
3-6
(MSB)
INFORMATION BYTE
(LSB)
7 ADDmONAL SENSE LENGTH (BYTES) =OA H
8-11 RESERVED = 0
12 ADDmONAL SENSE CODE
13 RESERVED=O
14 FRU FAILED = 0
15 FPV
CID
I
VU
I
VU
I
BPV
I
BIT POINTER = 0
16-17
(MSB)
FIELD POINTER
(LSB)
VALID - INFORMATION VALID (Byte 0, Bit 7) - Set to 1 if the information bytes
contain valid
data.
ERROR CLASS AND CODE (Byte 0, Bits 6-0) - Set to 70H to indicate extended status.
SEGMENT NUMBER (Byte 1) - Set to zero for the ProDrive.
FM - nLE MARK (Bit 7, Byte 2) - Indicates that a filemark has been read; set to zero for the
P,oDrive.
EOM - END-OF-MEDIUM (Byte 2, Bit 6) - Indicates that an end-of-medium condition
exists; set to zero for the
ProDrive.
ILl - INCORRECT LENGTH INDICA TOR (Byte 2, Bit 5) - Indicates that the requested
logical block length does not match the block length on the medium. This bit is normally set to zero
for the
ProDrive; an exception is in response to the READ BUFFER command, when the requested
transfer length is greater than the buffer size.
R - RESERVED (Byte 2, Bit 4) - Must be zero for the ProDrive.
SENSE KEY (Byte 2, Bits 3-0) - Values for sense key data are shown in Table 5-12.
INFORMATION
BYTES (Bytes 3-6) - If the VALID bit is 1, the information bytes are valid
and are defined as he logical block address associated with the sense key.
SCSI Programming Guidelines 5 -2 3