Fujitsu M2488, Руководство по эксплуатации продукта

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TAPE UNIT SCSI COMMANDS M2488 PRODUCT GUIDE
4-136 CG00000-011503 REV. A April 1997
4-3.29.2 SPACE CHECK CONDITION Status
If the Valid bit is set to 1 for Sense data for a CHECK CONDITION for a SPACE command, then
the Information field in the Sense data contains a count of the remainder of blocks or filemarks not
spaced over. If the spacing was in the reverse direction then the Information field value will be the
negative of this remainder. The Information field in this case is a 32 bit signed number, 2’s comple-
ment. In the case of a SPACE command by blocks stopped because a filemark was encountered,
the filemark is not counted as a block that was spaced over. The Information field is not valid (the
Valid bit is 0) for Sense data for a CHECK CONDITION when spacing to sequential filemarks.
Filemark Parameter:
If a filemark is encountered when spacing by blocks, the operation will stop. For forward spac-
ing the final position will be the End-of-Tape side of the filemark. For backward spacing the
final position will be the Beginning-of-Tape side of the filemark. CHECK CONDITION status
will be reported for the Space command. Sense data will indicate NO SENSE; the Filemark bit
will be 1; the Valid bit will be 1 and the Information field will be set as stated above.
End-of-Data Parameter:
If End-of-Data is encountered when spacing forward by blocks or filemarks (not to sequential
filemarks), the operation will stop and the tape-unit remains positioned at End-of-Data. CHECK
CONDITION status will be reported for the Space command. Sense data will indicate BLANK
CHECK; the Valid bit will be 1 and the Information field will be set as stated above.
If End-of-Data is encountered when spacing forward to sequential filemarks, the operation will
stop and the tape-unit remains positioned at End-of-Data. CHECK CONDITION status will be
reported for the Space command. Sense data will indicate BLANK CHECK; the Valid bit will
be 0.
End-of-Tape Parameter:
If End-of-Tape is encountered when spacing forward, the operation will stop and the tape-unit
remains positioned at End-of-Tape. CHECK CONDITION status will be reported for the Space
command. Sense data will indicate MEDIUM ERROR; the EOM bit will be 1; the Valid bit will
be 1 and the Information field will be set as stated above.
Beginning-of-Tape Parameter:
If Beginning-of-Tape is encountered when spacing backward by blocks or filemarks (not to
sequential filemarks), the operation will stop and the tape-unit remains positioned at Beginning-
of-Tape. CHECK CONDITION status will be reported for the Space command. Sense data will
indicate NO SENSE; the EOM bit will be 1; the Valid bit will be 1 and the Information field
will be set as stated above.
If Beginning-of-Tape is encountered when spacing backward to sequential filemarks, the opera-
tion will stop and the tape-unit remains positioned at Beginning-of-Tape. CHECK CONDI-
TION status will be reported for the Space command. Sense data will indicate NO SENSE; the
EOM bit will be 1; the Valid bit will be 0.
The Report Early-Warning (REW) bit in the Device Configuration Page is not supported by this
tape unit. No Early-Warning indication will occur when spacing.
100b-111b Invalid These codes are not used by the unit.
Table 4-126. Code Field Bits (Continued)
CODE FIELD TYPE DESCRIPTION