Reference Guide

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)