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Write specific status, Residue information – HP Q153090901 User Manual

Page 179

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WRITE 0Ah

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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.