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Chapter 4 SCSI Commands
READ POSITION Command (34h)
DLT-S4 Interface Reference Guide
271
Table 150
READ POSITION
Command Descriptor Block
—
Field Descriptions
Read Position Data —
Short Form
4
Data returned when the service action value is 00h or 01h takes the
following form:
Figure 135
READ POSITION
(Short Form) — Data Format
Field
Description
Service Action
Determines the format of the positional data the drive returns. All values other than
those listed below are reserved or unsupported.
Value
Description
00h
The drive returns 20 bytes of data in the format described in
Read Position
Data — Short Form
on page 270.
01h
The drive returns 20 bytes of data in the format described in
Read Position
Data — Short Form
on page 270.
06h
The drive returns 32 bytes of data in the format described in
Read Position
Data — Long Form
on page 273.
Allocation Length
Only used with service actions that are not supported by the DLT-S4. Must be zero.
Bit
7
6
5
4
3
2
1
0
Byte
0
BOP
EOP
LOCU
BYCU
Reserved
LOLU
PERR
Reserved
1
Partition Number
2 — 3
Reserved
4 — 7
(MSB)
First Logical Object Location
(LSB)