Quantum DLT 2000, Product Manual

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DLT2000 SCSI Interface
DLT2000/DLT2700 Cartridge Tape Subsystem 8-91
Incorrect Length Indicator (ILI) bit and Valid bit will be set to one. The Sense Key field
will be set to NO SENSE. The Information Bytes will be set to the difference (residue)
between the requested transfer length and the actual block length, or in Fixed Blocked
Mode, the difference (residue) between the requested number of blocks and the actual
number of blocks read. No more than transfer length bytes are transferred to the
initiator and the tape is logically positioned after the block (EOM side).
If the drive reads a Filemark, it will return a CHECK CONDITION status. Within the
Sense data, the Filemark and Valid bits are set and the Sense Key field is set to NO
SENSE. The Information fields contain the residue count. The Additional Sense Code
and Additional Sense Code Qualifier fields are set to Filemark Detected. Upon
termination, the media will be logically positioned after the Filemark (EOM side).
If the drive detects EOD during the READ, the drive will return a CHECK
CONDITION status. Within the Sense data, the Valid bit is set and the Sense Key field
is set to BLANK CHECK. The EOM bit may be set if the drive determines that the tape
is positioned past the PSEN marker. The information fields contain the residue count.
The Additional Sense Code and Additional Sense Code Qualifier fields are set. Upon
termination, the media will be physically positioned before EOD and after the last block
on tape.
The meaning of EOM is different for a read than for a write type of command. EOM is
only reported when the physical EOM/P is encountered. The drive returns a CHECK
CONDITION status. The EOM and Valid bits are set and the Sense Key is set to
MEDIUM ERROR. The information fields contain the residue count and the Additional
Sense Code and Additional Sense Code Qualifier fields are set to EOM/P Detected. The
tape is physically positioned at EOM/P.
If any READ command cannot be completed successfully the drive returns a CHECK
CONDITION status. Further commands should attempt to move past the error and
complete successfully.