User's Guide

Chapter 3 Emulated DLT7000 SCSI Commands
Space (11h)
266 Quantum DX-Series Software Interface Guide
Table 216 SPACE
Command Data - Field
Descriptions
When executing SPACE, the tape drive implements the following
hierarchy:
Field Name Description
Code The code can be one of the following:
Space CodeSpace by:
000b Blocks
001b Filemarks
010b Sequential Filemarks
011b End of Data
For 2.6 GB and 6.0 GB format, the tape drive
supports count values 0, 1, and 2 only. For 10.0 GB
and newer formats, compressed or noncompressed,
the count value can be from 0 to FFFFFFh.
Count When spacing over blocks or marks, the Count field
is interpreted as follows:
A positive value N causes forward motion over N
blocks or marks. The tape is logically positioned
after the Nth block or mark on the EOM or EOP
side.
A value of 0 causes no change in logical position.
A negative value -N (two’s complement notation)
causes reverse movement over N blocks or marks.
The tape is logically positioned on the BOM or BOP
side of the Nth block or mark.
When spacing to EOD, the Count field is ignored.
Forward movement occurs until the drive
encounters EOD. The position is such that a
subsequent WRITE command would append data
after the last object that has been written to tape
before EOD.