![background image](http://html2.mh-extra.com/html/quantum/dlttape-dlt-8000/dlttape-dlt-8000_product-manual_3551923148.webp)
SCSI Commands
5-4
Quantum DLT 8000 Tape System
5.1.2 Command Descriptor Block
An initiator communicates with the drive by sending a 6- or 10-byte Command
Descriptor Block that contains the parameters for the specific command. The SCSI
command's operation code is always the first byte in the Command Descriptor Block and
a control field is the last byte. For some commands, the Command Descriptor Block is
accompanied by a list of parameters sent during the DATA OUT phase. Figure 5–1
shows the format of a typical 6-byte Command Descriptor Block. Table 5–2 contains a
description of the Command Descriptor Block fields.
Bit
Byte
7
6
5
4
3
2
1
0
0
Operation Code
1
Logical Unit Number
(LUN)
(MSB)
Logical Block Address
(LBA)
2 - 3
Logical Block Address
(LBA)
(LSB)
4
Transfer Length, Parameter List Length, or Allocation Length
5
Control
NOTE: Unless otherwise specified, all reserved bits indicated in the commands are 0.
The Control byte is described on Page 5-6.
Figure 5–1 Typical 6-Byte Command Descriptor Block — Data Format
Summary of Contents for DLTtape DLT 8000
Page 1: ...DLTTM 8000 Tape System Product Manual Nov 10 2003 81 60118 06...
Page 5: ...USER MANUAL STATEMENTS FOR CLASS B EQUIPMENT continued...
Page 6: ......
Page 26: ...Table of Contents xxiv Quantum DLT 8000 Tape System...
Page 36: ...About This Manual Quantum DLT 8000 Tape System xxxii...
Page 54: ...General Description and Specifications 1 18 Quantum DLT 8000 Tape System...
Page 102: ......
Page 372: ......
Page 376: ...Appendix A Definition of Vendor Unique Sense Data Information A 4 Quantum DLT 8000 Tape System...
Page 386: ...Appendix C Updating the Firmware C 6 Quantum DLT 8000 Tape System...
Page 396: ...Appendix E Visual Inspection Procedure for DLTtape Cartridges E 8 Quantum DLT 8000 Tape System...
Page 406: ...Appendix G DLT 7000 Emulation Feature G 8 Quantum DLT 8000 Tape System...
Page 407: ......