Write specific status, Residue information – HP Q153090901 User Manual
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WRITE 0Ah
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omm
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Write specific status:
See also the “Additional Sense codes” on page 159 for a variety of possible hard errors.
An attempt to write to a write-protected cartridge will produce a
CHECK CONDITION
with a sense
key of
DATA PROTECT
and additional sense of 2700h (write-protected).
An attempt to write to a cartridge whose Cartridge Memory has failed will produce a
CHECK
CONDITION
with a sense key of
MEDIUM ERROR
and additional sense of 3004h (cannot write
medium). If, however, the tape is not positioned at BOT, the drive will respond with sense data as
if the tape is write-protected. The WP flag in the Mode Parameter Header will also be set.
If EOM (end of medium) is encountered during a write,
CHECK CONDITION
status is reported. The
EOM flag will be set. The sense key will be set to
VOLUME OVERFLOW
with additional sense of
0002h (EOT). Residue information will be as below. The logical position will be EOD.
Subsequent Request Sense commands will, however, give tape position as EOP/M. It may still be
possible to write a smaller quantity of information (such as filemarks or a smaller block). This is
because logical position after failure to write a block returns to the start of the unwritten block.
Early Warning EOM information is reported only if a write operation is successful. This is done by
reporting
CHECK CONDITION
status with a sense key of
NO SENSE
and additional sense of 0002h
(EOT). Residue information is valid and indicates zero blocks/bytes.
Residue information:
Residue information depends on two variables:
•
Fixed or Variable block mode.
•
Immediate or Non-Immediate Report (Buffered mode).
Residue information is set in the sense data byte, with the Valid bit set and the information bytes
set to the residue.
Block Mode
Buffered Mode Residue
Variable
0
Number of unwritten bytes
Fixed
0
Number of unwritten blocks
Variable
not 0
Total number of unwritten bytes and marks (including those buffered
before the command was received). The size can be greater than the
command operation size.
specifically 1
Contains residues of all initiators with data in the buffer.
Fixed
not 0
Total number of unwritten blocks and marks (including those buffered
before the command was received). The size can be greater than the
command operation size.
specifically 1
Contains residues of all initiators with data in the buffer.