Quantum DLT4000 User Manual

DLT4000 Tape Drive
Product Manual
November 10, 2003
81-60043-04
Quantum reserves the right to make changes and improvements to its products, without incurring any obligation to incorporate such changes or improvements in units previously sold or shipped. Quantum reserves the right to make changes to this product manual without incurring any obligation to notify recipients of earlier versions of the product manual.
You can request Quantum publications from your Quantum Sales Representative or order them directly from Quantum.
Publication Number: 81-60043-04, November 10, 2003
SERVICE CENTERS
Quantum Service Center Quantum Asia-Pacific Pte. Ltd. Quantum Customer Service 715 Sycamore Avenue 50 Tagore Lane #b1-04 Quantum Ireland, Ltd. Milpitas, California 95035 Singapore, 2678 Finnabair Industrial Park Phone (888) 827-3378 Phone: (65) 450-9333 Dundalk FAX: (800) 4DISKFAX FAX: (65) 452-2544 County Louth, Ireland BBS: (800) 472-9799 Phone: (353) 42-55350 Fax: (353) 45-55355
Copyright 1995-2001 by Quantum Corporation. All rights reserved. Printed in U.S.A. Quantum and the Quantum logo are trademarks of Quantum Corporation, registered in the U.S.A.
and other countries. DLTtape and the DLTtape logo are trademarks of Quantum Corporation. Products mentioned herein are for identification purposes only and may be trademarks or registered trademarks of their respective companies.
USER MANUAL STATEMENTS FOR CLASS A EQUIPMENT (INTEGRATIBLE TAPE SYSTEM)
This equipment generates, uses, and may emit radio frequency energy. The equipment has been type tested and found to comply with the limits for a Class A digital device pursuant to Part 15 of FCC rules, which are designed to provide reasonable protection against such radio frequency interference.
Operation of this equipment in a residential area may cause interference in which case the user at his own expense will be required to take whatever measures may be required to correct the interference.
Any modifications to this device - unless expressly approved by the manufacturer - can void the user’s authority to operate this equipment under part 15 of the FCC rules.
Note: Additional information on the need to interconnect the device with shielded (data) cables or the need for special devices, such as ferrite beads on cables, is required if such means of interference suppression was used in the qualification test for the device. This information will vary from device to device and needs to be obtained from the EMC group or product manager.
Warning!
This is a Class A product. In a domestic environment this product may cause radio interference in which case the user may be required to take adequate measures.
Achtung!
Dieses ist ein Gerät der Funkstörgrenzwertklasse A. In Wohnbereichen können bei Betrieb dieses Gerätes Rundfunkstörungen auftreten, in welchen Fällen der Benutzer für entsprechende Gegenmaßnahmen verantwortlich ist.
Warning!
This Class A digital apparatus complies with Canadian ICES-003.
Cet appareil numérique de la classe A est conforme à la norme NMB-003 du Canada.
Attention!
Ceci est un produit de Classe A. Dans un environnement domestique, ce produit risque de créer des interférences radioélectriques, il appartiendra alors à l'utilisateur de prendre les mesures spécifiques appropriées.
USER MANUAL STATEMENTS FOR CLASS A EQUIPMENT (continued)
USER MANUAL STATEMENTS FOR CLASS B EQUIPMENT (TABLETOP VERSION)
This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to Part 15 of the FCC rules. These limits are designed to provide reasonable protection against harmful interference in a residential installation. Any modifications to this device ­unless expressly approved by the manufacturer - can void the user’s authority to operate this equipment under part 15 of the FCC rules. Operation is subject to the following two conditions: (1) This device may not cause harmful interference and (2) This device must accept any interference that may cause undesirable operation.
This equipment generates, uses, and can radiate radio frequency energy and, if not installed and used in accordance with the instructions, may cause harmful interference to radio communications. However, there is no guarantee that interference will not occur in a particular installation. If this equipment does cause harmful interference to radio or television reception, which can be determined by turning the equipment off and on, the user is encouraged to try to correct the interference by one or more of the following measures:
Reorient or relocate the receiving antenna.
Increase the separation between the equipment and receiver.
Connect the equipment into an outlet on a circuit different from that to which the receiver is
connected
Consult the dealer or an experienced radio/TV technician for help.
Note: Additional information on the need to interconnect the device with shielded (data) cables or the need for special devices, such as ferrite beads on cables, is required if such means of interference suppression was used in the qualification test for the device. This information will vary from device to device and needs to be obtained from the EMC group or product manager.
This Class B digital apparatus complies with Canadian ICES-003. Cet appareil numérique de la classe B est conforme à la norme NMB-003 du Canada.
USER MANUAL STATEMENTS FOR CLASS B EQUIPMENT (continued)
TABLE OF CONTENTS
Revision History........................................................................................................ xix
About This Manual .................................................................................................. xxi
Chapter 1: General Description and Specifications.................................................... 1-1
1.1 Product Description.............................................................................. 1-1
1.2 Product Features ................................................................................. 1-3
1.3 Product Specifications .......................................................................... 1-3
1.3.1 Physical Specifications ................................................................. 1-3
1.3.2 Interface Type............................................................................. 1-4
1.3.3 Storage Capacity......................................................................... 1-4
1.3.4 Performance Data....................................................................... 1-4
1.3.5 Environmental Specifications....................................................... 1-5
1.3.6 Power Requirements................................................................... 1-7
1.3.7 Electromagnetic Emissions........................................................... 1-7
1.3.8 EMI and Safety Certifications....................................................... 1-8
1.3.9 Reliability (Projected) ................................................................... 1-8
1.3.10 Acoustic Noise Emissions.............................................................. 1-9
1.3.11 Tape Drive Recording Type .......................................................... 1-9
1.3.12 DLTtape Recording Media Specifications...................................... 1-10
Chapter 2: Hardware Implementation ..................................................................... 2-1
2.1 Safety, Handling and Electrostatic Discharge (ESD) Protection ................ 2-1
2.1.1 Safety Precautions ...................................................................... 2-2
2.1.2 Handling .................................................................................... 2-2
2.1.3 Electrostatic Discharge (ESD) Protection ....................................... 2-3
2.2 Drive Setup .......................................................................................... 2-3
2.2.1 Set the Rackmount Drive SCSI ID.................................................. 2-4
2.2.2 Configure the Rackmount Drive for TERMPWR
(Single-Ended Only)..................................................................... 2-6
2.2.3 Configure the Rackmount Drive for Parity Checking ..................... 2-7
2.2.4 Configure the Tabletop Drive ...................................................... 2-7
2.3 Drive Installation................................................................................... 2-8
2.4 Drive Connections ................................................................................ 2-10
2.4.1 SCSI and Power Connectors (Rackmount)..................................... 2-11
2.4.2 Optional Loader Connector (Rackmount) ..................................... 2-14
2.4.3 Tabletop Drive Connectors.......................................................... 2-15
2.5 Drive Controls and Light Emitting Diodes (LEDs)..................................... 2-17
2.5.1 Front Panel Controls and LEDs..................................................... 2-17
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2.5.2 Selecting Density......................................................................... 2-21
2.6 Power On Self Test (POST).................................................................... 2-23
2.7 Troubleshooting................................................................................... 2-25
Chapter 3: SCSI Description..................................................................................... 3-1
3.1 SCSI Overview ...................................................................................... 3-1
3.2 SCSI Commands.................................................................................... 3-1
3.3 Signal States ........................................................................................ 3-4
3.3.1 Signal Values .............................................................................. 3-4
3.3.2 SCSI ID Bits.................................................................................. 3-6
3.4 SCSI Signals.......................................................................................... 3-6
3.4.1 SCSI Signal Definitions................................................................. 3-6
3.4.2 Signal Bus Timing........................................................................ 3-7
3.5 SCSI Bus Phases .................................................................................... 3-10
3.5.1 BUS FREE Phase ........................................................................... 3-10
3.5.2 ARBITRATION Phase ..................................................................... 3-12
3.5.3 SELECTION Phase ........................................................................ 3-13
3.5.4 RESELECTION Phase ..................................................................... 3-15
3.5.5 Information Transfer Phases........................................................ 3-17
3.6 SCSI Bus Conditions.............................................................................. 3-24
3.6.1 Attention Condition.................................................................... 3-24
3.6.2 Reset Condition .......................................................................... 3-25
3.6.3 Queued Unit Attentions.............................................................. 3-26
Chapter 4: Messages............................................................................................... 4-1
4.1 Message Format ................................................................................... 4-1
4.2 Supported SCSI Messages..................................................................... 4-5
4.2.1 ABORT Message (06h)................................................................. 4-5
4.2.2 BUS DEVICE RESET Message (0Ch) ............................................... 4-5
4.2.3 COMMAND COMPLETE Message (00h) ........................................ 4-5
4.2.4 DISCONNECT Message (04h) ....................................................... 4-6
4.2.5 IDENTIFY Message (80h - FFh)...................................................... 4-7
4.2.6 INITIATOR DETECTED ERROR Message (05h) ................................. 4-8
4.2.7 LINKED COMMAND COMPLETE Message (0Ah) ............................. 4-9
4.2.8 LINKED COMMAND COMPLETE, with Flag Message (0Ah).............. 4-9
4.2.9 MESSAGE PARITY ERROR Message (09h)....................................... 4-9
4.2.10 MESSAGE REJECT Message (07h)................................................. 4-9
4.2.11 NO OPERATION Message (08h).................................................... 4-10
4.2.12 RESTORE POINTERS Message (03h) .............................................. 4-10
4.2.13 SAVE DATA POINTER Message (02h)............................................ 4-10
4.2.14 SYNCHRONOUS DATA TRANSFER REQUEST Message ..................... 4-10
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Chapter 5: SCSI Commands..................................................................................... 5-1
5.1 Overview of Command and Status Processing........................................ 5-1
5.1.1 SCSI Pointers............................................................................... 5-3
5.1.2 Command Descriptor Block.......................................................... 5-4
5.1.3 Status/Error Reporting ................................................................ 5-7
5.1.4 DATA-Phase Command Components............................................ 5-8
5.1.5 Unit Attention Condition ............................................................ 5-11
5.1.6 Behavior At Power-On and SCSI Bus Reset.................................... 5-11
5.1.7 Data Cache and Tape Write Interaction........................................ 5-12
5.2 SCSI Command Descriptions.................................................................. 5-13
5.3 ERASE Command (19h) ......................................................................... 5-15
5.4 INQUIRY Command (12h)...................................................................... 5-17
5.4.1 Standard Inquiry Data Page......................................................... 5-18
5.4.2 Vendor Unique Inquiry Data........................................................ 5-21
5.4.3 Supported Vital Product Data Page (00h)..................................... 5-24
5.5 LOAD UNLOAD Command (1Bh)........................................................... 5-27
5.6 LOCATE Command (2Bh)...................................................................... 5-31
5.7 LOG SELECT Command (4Ch)................................................................. 5-33
5.7.1 Log Detection Summary in LOG SELECT Command
Descriptor Block .......................................................................... 5-35
5.7.2 Operation of LOG SELECT............................................................ 5-35
5.7.3 LOG SELECT Page Format ............................................................ 5-36
5.7.4 Error Detection Summary in LOG SELECT Pages............................ 5-39
5.8 LOG SENSE Command (4Dh).................................................................. 5-41
5.8.1 Error Detection Summary in LOG SENSE Command
Descriptor Block .......................................................................... 5-44
5.8.2 Supported Pages Log Page (00h)................................................. 5-45
5.8.3 Read (Page 03h)/Write (Page 02h) Error LOG SENSE Page.............. 5-46
5.8.4 Last n Error Events Page (07h) ..................................................... 5-49
5.8.5 Read/Write Compression Page (32h)............................................. 5-52
5.8.6 Device Wellness Page (33h).......................................................... 5-57
5.8.7 Device Status Page (3Eh) ............................................................. 5-60
5.9 MODE SELECT (6) / (10) Command (15h / 55h)....................................... 5-63
5.9.1 Mode Parameter List ................................................................... 5-65
5.9.2 Read/Write Error Recovery Page (01h) .......................................... 5-72
5.9.3 Disconnect/Reconnect Page ........................................................ 5-73
5.9.4 Control Mode Page (0Ah)............................................................ 5-77
5.9.5 Data Compression Page (0Fh) ...................................................... 5-79
5.9.6 Device Configuration Page (10h).................................................. 5-81
5.9.7 Medium Partition Page (11h)....................................................... 5-84
5.9.8 EEPROM Vendor Unique Page (3Eh)............................................. 5-86
5.9.9 Changeable Parameters within MODE SELECT .............................. 5-93
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5.10 MODE SENSE (6) / (10) Command (1Ah / 5Ah)....................................... 5-95
5.10.1 MODE SENSE Data Headers......................................................... 5-98
5.10.2 MODE SENSE Block Descriptors....................................................5-100
5.10.3 MODE SENSE Mode Pages...........................................................5-102
5.11 PREVENT / ALLOW MEDIUM REMOVAL Command (1Eh)..........................5-119
5.12 READ Command (08h)...........................................................................5-121
5.13 READ BLOCK LIMITS Command (05h) .....................................................5-125
5.14 READ BUFFER Command (3Ch)..............................................................5-127
5.14.1 Combined Header and Data Mode ..............................................5-128
5.14.2 Data Mode ................................................................................5-129
5.14.3 Descriptor Mode ........................................................................5-129
5.15 READ POSITION Command (34h)............................................................5-131
5.16 RECEIVE DIAGNOSTIC RESULTS Command (1Ch)......................................5-135
5.17 RELEASE UNIT Command (17h)..............................................................5-137
5.18 REPORT LUNS Command (0Ah).............................................................. 5-139
5.19 REQUEST SENSE Command (03h)...........................................................5-141
5.20 RESERVE UNIT Command (16h).............................................................5-151
5.21 REWIND Command (01h).......................................................................5-153
5.22 SEND DIAGNOSTIC Command (1Dh).......................................................5-155
5.23 SPACE Command (11h)........................................................................5-161
5.24 TEST UNIT READY Command (00h).........................................................5-163
5.25 VERIFY Command (13h).........................................................................5-165
5.26 WRITE Command (0Ah).........................................................................5-167
5.27 WRITE BUFFER Command (3Bh)..............................................................5-169
5.27.1 Write Combined Header and Data Mode (000b) ...........................5-170
5.27.2 Write Data Mode (010b)..............................................................5-170
5.27.3 Download Microcode Mode (100b)..............................................5-171
5.27.4 Download Microcode and Save Mode (101b) ...............................5-171
5.28 WRITE FILEMARKS Command (10h) .......................................................5-173
Appendix A: Definition of Vendor Unique Sense Data Information ...................................................... A-1
Appendix B: EEPROM-Resident Bugcheck and Event Logs .................................................................... B-1
B.1 EEPROM Packets (Last n Events)........................................................................................ B-1
B.2 Bugcheck Packets................................................................................................................ B-1
B.2.1 POST Failure Packets............................................................................................... B-2
B.2.2 Event Log Packets................................................................................................... B-3
Appendix C: Updating the Firmware.......................................................................................................... C-1
C.1 Overview .............................................................................................................................. C-1
C.2 Creating a Firmware Update Tape .................................................................................... C-1
C.3 Firmware Update Procedure.............................................................................................. C-2
C.4 Interpreting the Results of a Firmware Update ............................................................... C-4
Appendix D: The Tape Cartridge ................................................................................................................ D-1
D.1 Tape Cartridge Handling Guidelines ................................................................................ D-1
D.2 Tape Cartridge Inspection Procedure................................................................................ D-4
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D.3 Tape Cartridge Write-Protect Switch ..................................................... D-8
D.4 Loading a Tape Cartridge ..................................................................... D-10
D.5 Unloading a Tape Cartridge .................................................................. D-11
D.6 Using a Cleaning Tape Cartridge ........................................................... D-12
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Figures
Figure 1-1. Quantum DLT 4000 Tape Drive (Rackmount)............................................ 1-2
Figure 1-2. Quantum DLT 4000 Tape Drive (Tabletop) ............................................... 1-2
Figure 2-1. DLT 4000 SCSI ID Jumper Location (Rackmount Version Shown)............... 2-4
Figure 2-2. DLT 4000 TERMPWR and Parity Check Jumper Locations
(Rackmount Version Shown) .................................................................. 2-6
Figure 2-3. Tabletop (Version 1) Back Panel Controls................................................. 2-7
Figure 2-4. Tabletop (Version 2) Back Panel Controls................................................. 2-8
Figure 2-5. Rackmount Drive Mounting Locations – Side and Bottom Views .............. 2-9
Figure 2-6. SCSI and Power Cable Connectors (Rackmount Version Shown)............... 2-11
Figure 2-7. Loader Connector Block Location (Rackmount Version Shown)................ 2-14
Figure 2-8. Tabletop (Version 1) Back Panel Connectors............................................ 2-15
Figure 2-9. Tabletop (Version 2) Back Panel Connectors............................................ 2-16
Figure 2-10. DLT 4000 Front Panel............................................................................ 2-17
Figure 4-1. Extended Message - Data Format............................................................ 4-4
Figure 4-2. IDENTIFY Message - Data Format............................................................. 4-7
Figure 4-3. SYNCHRONOUS DATA TRANSFER REQUEST Message - Data Format........... 4-11
Figure 5-1. Typical Command Descriptor Block - Data Format .................................... 5-4
Figure 5-2. Command Descriptor Block Control Field - Data Format ........................... 5-6
Figure 5-3. ERASE Command Descriptor Block - Data Format..................................... 5-15
Figure 5-4. INQUIRY Command Descriptor Block - Data Format .................................. 5-17
Figure 5-5. Standard Inquiry Data Page - Data Format .............................................. 5-19
Figure 5-6. INQUIRY Vendor Unique Bytes Definitions................................................ 5-22
Figure 5-7. Supported Vital Product Data Pages Page - Data Format ......................... 5-24
Figure 5-8. Unit Serial Number Page - Data Format................................................... 5-25
Figure 5-9. Firmware Build Information Page - Data Format ...................................... 5-26
Figure 5-10. LOAD UNLOAD Command Descriptor Block - Data Format....................... 5-28
Figure 5-11. LOCATE Command Descriptor Block - Data Format................................. 5-31
Figure 5-12. LOG SELECT Command Descriptor Block - Data Format........................... 5-33
Figure 5-13. LOG SELECT Log Page Header Format ................................................... 5-36
Figure 5-14. LOG SELECT Log Parameters Format...................................................... 5-37
Figure 5-15. LOG SENSE Command Descriptor Block - Data Format............................ 5-41
Figure 5-16. Supported Pages Page - Data Format.................................................... 5-45
Figure 5-17. Read/Write Error LOG SENSE Header Format.......................................... 5-46
Figure 5-18. Log Parameters Format for Read/Write Error LOG SENSE Page................ 5-47
Figure 5-19. Last n Error Events LOG SENSE Header Format....................................... 5-50
Figure 5-20. Log Parameters Format for Last n Error Events LOG SENSE Page ............ 5-51
Figure 5-21. Read/Write Compression Ratio LOG SENSE Header Format...................... 5-52
Figure 5-22. Log Parameters Format for Read / Write Compression Ratio LOG SENSE
Page (Parameter Codes 00h and 01h) ..................................................... 5-53
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Figure 5-23 Log Parameters Format for Read / Write Compression Ratio LOG SENSE
Page (Parameter Codes 02h through 09h)............................................... 5-54
Figure 5-24. Device Wellness LOG SENSE Header Format ........................................... 5-57
Figure 5-25. Log Parameters Format for Device Wellness LOG SENSE Page
(Parameters 0000h – 000Fh) ................................................................... 5-58
Figure 5-26. Device Status LOG SENSE Header Format................................................ 5-60
Figure 5-27. Log Parameters Format for Device Status LOG SENSE Page
(Parameters 0000h, 0001h, or 0002h) ..................................................... 5-61
Figure 5-28. Log Parameters Format for Device Status LOG SENSE Page
Parameter 0001h (Cleaning Related) ....................................................... 5-62
Figure 5-29. MODE SELECT (6) and (10) Command Descriptor Blocks - Data Format ..... 5-64
Figure 5-30. MODE SELECT Mode Parameter List - Data Format.................................. 5-65
Figure 5-31. MODE SELECT Mode Parameter Header - Data Format............................ 5-66
Figure 5-32. MODE SELECT Mode Parameter Block Descriptor - Data Format............... 5-68
Figure 5-33. MODE SELECT Page Descriptor – Page Format ........................................ 5-70
Figure 5-34. Error Recovery Page - Data Format......................................................... 5-72
Figure 5-35. Disconnect / Reconnect Page - Data Format............................................ 5-74
Figure 5-36. Control Mode Page Format Descriptor - Data Format.............................. 5-77
Figure 5-37. Data Compression Page Format Descriptor - Data Format........................ 5-79
Figure 5-38. Device Configuration Page - Data Format............................................... 5-81
Figure 5-39. Medium Partition Page Format Descriptor - Data Format......................... 5-84
Figure 5-40. EEPROM Vendor Unique Page - Data Format .......................................... 5-86
Figure 5-41. EEPROM Vendor Unique Page “Vendor ID” Example - Data Format.......... 5-91
Figure 5-42. EEPROM Vendor Unique Page “Forced Density” Example - Data Format ... 5-92
Figure 5-43. MODE SENSE (6) Command Descriptor Block - Data Format..................... 5-95
Figure 5-44. MODE SENSE (10) Command Descriptor Block - Data Format ................... 5-96
Figure 5-45. MODE SENSE (6) Data Header - Data Format .......................................... 5-98
Figure 5-46. MODE SENSE (10) Data Header - Data Format......................................... 5-98
Figure 5-47. MODE SENSE (6) Block Descriptor - Data Format .....................................5-100
Figure 5-48. MODE SENSE Page Descriptor - Data Format ..........................................5-102
Figure 5-49. Read / Write Error Recovery Page - Data Format......................................5-104
Figure 5-50. Disconnect / Reconnect Page - Data Format............................................5-106
Figure 5-51. Control Mode Page - Data Format .........................................................5-108
Figure 5-52. Data Compression Page - Data Format .................................................5-110
Figure 5-53. Device Configuration Page - Data Format.............................................5-112
Figure 5-54. Medium Partition Page - Data Format ..................................................5-115
Figure 5-55. PREVENT / ALLOW MEDIUM REMOVAL Command Descriptor Block -
Data Format ..........................................................................................5-119
Figure 5-56. READ Command Descriptor Block - Data Format .....................................5-121
Figure 5-57. READ BLOCK LIMITS Command Descriptor Block - Data Format ................5-125
Figure 5-58. READ BLOCK LIMITS Data - Data Format .................................................5-126
Figure 5-59. READ BUFFER Command Descriptor Block - Data Format..........................5-127
Figure 5-60. READ BUFFER Header - Data Format .......................................................5-128
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Figure 5-61. READ BUFFER Descriptor - Data Format...................................................5-129
Figure 5-62. READ POSITION Command Descriptor Block - Data Format ......................5-131
Figure 5-63. READ POSITION - Data Format................................................................5-132
Figure 5-64. RECEIVE DIAGNOSTICS RESULTS Command Descriptor Block –
Data Format ..........................................................................................5-135
Figure 5-65. RECEIVE DIAGNOSTICS RESULTS - Data Format ........................................5-136
Figure 5-66. RELEASE UNIT Command Descriptor Block - Data Format.........................5-137
Figure 5-67. REPORT LUNS Command Descriptor Block - Data Format .........................5-139
Figure 5-68. LUN Reporting Parameter List — Data Format.........................................5-140
Figure 5-69. REQUEST SENSE Command Descriptor Block - Data Format......................5-141
Figure 5-70. REQUEST SENSE - Data Format...............................................................5-143
Figure 5-71. RESERVE UNIT Command Descriptor Block - Data Format.........................5-151
Figure 5-72. REWIND Command Descriptor Block - Data Format..................................5-153
Figure 5-73. SEND DIAGNOSTIC Command Descriptor Block - Data Format..................5-155
Figure 5-74. SEND DIAGNOSTIC Parameter List - Data Format .....................................5-157
Figure 5-75. SPACE Command Descriptor Block - Data Format....................................5-161
Figure 5-76. TEST UNIT READY Command Descriptor Block - Data Format....................5-163
Figure 5-77. VERIFY Command Descriptor Block - Data Format....................................5-165
Figure 5-78. WRITE Command Descriptor Block - Data Format ....................................5-167
Figure 5-79. WRITE BUFFER Command Descriptor Block - Data Format.........................5-169
Figure 5-80. WRITE FILEMARKS Command Descriptor Block - Data Format ...................5-173
Figure A-1. Internal Status Bits................................................................................. A-4
Figure B-1. Directory Failure Event Package – Data Format........................................ B-5
Figure D-1. Location of the Two Reel Lock Tabs on the DLTtape Cartridge ................ D-4
Figure D-2. Location of Reel Lock Opening and Spring-Loaded Hub on
Bottom of DLTtape Cartridge ................................................................. D-5
Figure D-3. Opening the Door on a DLTtape Cartridge Showing Tape
Leader Loop in its Correct Position ......................................................... D-6
Figure D-4. Three Examples of Tape Cartridges with Damage Visible During
Visual Inspection.................................................................................... D-7
Figure D-5. Write-Protect Switch on Tape Cartridge.................................................. D-8
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Tables
Table 1-1. DLT 4000 Physical Dimensions................................................................. 1-3
Table 1-2. DLT 4000 Storage Capacity..................................................................... 1-4
Table 1-3. DLT 4000 Performance Data ................................................................... 1-4
Table 1-4. DLT 4000 Environmental Specifications ................................................... 1-5
Table 1-5. DLT 4000 Non-Operating Shock Specifications ........................................ 1-6
Table 1-6. DLT 4000 Non-Operating Vibration Specifications.................................... 1-6
Table 1-7. DLT 4000 Power Requirements ............................................................... 1-7
Table 1-8. EMI Emission Certificates........................................................................ 1-8
Table 1-9. Safety Certifications............................................................................... 1-8
Table 1-10. Acoustic Noise Emissions, Nominal (English) ........................................... 1-9
Table 1-11. Acoustic Noise Emissions for German Noise Declaration Law.................... 1-9
Table 1-12. DLTtape Media Specifications................................................................. 1-10
Table 2-1. SCSI ID Address Selections...................................................................... 2-5
Table 2-2. Single-Ended SCSI Pin Assignment .......................................................... 2-12
Table 2-3. Differential SCSI Pin Assignment............................................................. 2-13
Table 2-4. 4-Pin Power Connector Pin Assignment .................................................. 2-14
Table 2-5. LED Functionality ................................................................................... 2-18
Table 2-6. Density LED Functionality ....................................................................... 2-19
Table 2-7. Control Functionality ............................................................................. 2-20
Table 2-8. LED Activity During Density Selection...................................................... 2-23
Table 2-9. POST/Media Ready Activity ..................................................................... 2-24
Table 2-10. Tape Drive States Following Initialization ................................................ 2-24
Table 2-11. Troubleshooting Chart........................................................................... 2-25
Table 3-1. Implemented ANSI SCSI-2 Commands...................................................... 3-2
Table 3-2. Signal Sources....................................................................................... 3-5
Table 3-3. SCSI-2 Bus Signal Definitions................................................................... 3-6
Table 3-4. SCSI Bus Timing Values........................................................................... 3-8
Table 3-5. Information Transfer Phases................................................................... 3-19
Table 3-6. Status Bytes........................................................................................... 3-23
Table 3-7. Drive MESSAGE OUT Phase Response ...................................................... 3-25
Table 4-1. Message Format .................................................................................... 4-2
Table 4-2. Supported Messages.............................................................................. 4-3
Table 4-3. Extended Message - Field Description ..................................................... 4-4
Table 4-4. Drive Response to DISCONNECT Message ................................................ 4-6
Table 4-5. IDENTIFY Message - Field Description....................................................... 4-7
Table 4-6. Drive Response to INITIATOR DETECTED ERROR Message .......................... 4-8
Table 5-1. Supported SCSI Commands.................................................................... 5-1
Table 5-2. Command Descriptor Block - Field Descriptions........................................ 5-5
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Table 5-3. Command Descriptor Block Control Field - Field Descriptions.................... 5-6
Table 5-4. Status Codes ......................................................................................... 5-8
Table 5-5. Length Field Name Units ........................................................................ 5-9
Table 5-6. DATA-Phase Command Contents............................................................ 5-9
Table 5-7. ERASE Command Descriptor Block - Field Descriptions ............................. 5-16
Table 5-8. INQUIRY Command Descriptor Block - Field Descriptions........................... 5-18
Table 5-9. Vital Product Data - Page Codes............................................................. 5-18
Table 5-10. Standard Inquiry Data Page - Field Descriptions....................................... 5-20
Table 5-11. Vendor Unique Inquiry Data Page – Field Descriptions............................. 5-23
Table 5-12. Unit Serial Number Page - Field Descriptions........................................... 5-25
Table 5-13. Firmware Build Information Page - Field Descriptions.............................. 5-26
Table 5-14. LOAD UNLOAD Command Descriptor Block - Field Descriptions................ 5-29
Table 5-15. LOCATE Command Descriptor Block – Field Descriptions.......................... 5-32
Table 5-16. LOG SELECT Command Descriptor Block - Field Descriptions..................... 5-34
Table 5-17. LOG SELECT Log Page Header Field Descriptions ..................................... 5-36
Table 5-18. LOG SELECT Log Parameters Field Descriptions........................................ 5-37
Table 5-19. LOG SENSE Command Descriptor Block - Field Descriptions...................... 5-42
Table 5-20. Read / Write Error LOG SENSE Header Field Descriptions.......................... 5-46
Table 5-21. Log Parameters for Read / Write Error LOG SENSE Page Field
Descriptions........................................................................................... 5-47
Table 5-22. Last n Error Events LOG SENSE Header Field Descriptions......................... 5-50
Table 5-23. Log Parameters for Last n Error Events LOG SENSE Page Field
Descriptions........................................................................................... 5-51
Table 5-24. Read / Write Compression Ratio LOG SENSE Header Field Descriptions...... 5-52
Table 5-25. Log Parameters for Read / Write Compression Ratio LOG SENSE Page
Field Descriptions (Parameter Codes 00h and 01h)................................... 5-53
Table 5-26. Log Parameters for Read / Write Compression Ratio LOG SENSE Page
Field Descriptions (Parameter Codes 02h through 09h)............................ 5-54
Table 5-27. Device Wellness LOG SENSE Header Field Descriptions ............................. 5-57
Table 5-28. Log Parameters for Device Wellness LOG SENSE Page Field Descriptions ... 5-59
Table 5-29. Device Status LOG SENSE Header Field Descriptions................................. 5-60
Table 5-30. Log Parameters for Device Status LOG SENSE Page Field Descriptions....... 5-61
Table 5-31. Log Parameters for Device Wellness LOG SENSE Parameter 0001h
(Cleaning Related) Field Descriptions....................................................... 5-62
Table 5-32. MODE SELECT (6) (10) Command Descriptor Block - Field Descriptions...... 5-65
Table 5-33. MODE SELECT Mode Parameter List - Field Definitions............................. 5-66
Table 5-34. MODE SELECT Mode Parameter Header - Field Descriptions..................... 5-67
Table 5-35. MODE SELECT Mode Parameter Block Descriptor - Field Descriptions........ 5-69
Table 5-36. MODE SELECT Page Descriptor - Field Descriptions.................................. 5-71
Table 5-37. Error Recovery Page - Field Descriptions.................................................. 5-73
Table 5-38. Disconnect / Reconnect Page - Field Descriptions..................................... 5-75
Table 5-39. Control Mode Page Descriptor – Field Descriptions ................................. 5-78
xvi Quantum DLT 4000 Tape Drive
Table of Contents
Table 5-40. Data Compression Page Descriptor – Field Descriptions ........................... 5-80
Table 5-41. Device Configuration Page - Field Descriptions........................................ 5-82
Table 5-42. Medium Partition Page Descriptor - Field Descriptions............................. 5-85
Table 5-43. EEPROM Vendor Unique Page Parameters ............................................. 5-86
Table 5-44. Changeable Parameters within MODE SELECT......................................... 5-93
Table 5-45. MODE SENSE Command Descriptor Block - Field Descriptions................... 5-97
Table 5-46. MODE SENSE Data Header - Field Descriptions........................................ 5-99
Table 5-47. MODE SENSE Block Descriptor - Field Descriptions...................................5-101
Table 5-48. MODE SENSE Page Descriptor - Field Descriptions ...................................5-103
Table 5-49. Read / Write Error Recovery Page - Field Descriptions...............................5-105
Table 5-50. Disconnect / Reconnect Error Recovery Page - Field Descriptions..............5-107
Table 5-51. Control Mode Page – Field Descriptions..................................................5-109
Table 5-52. Data Compression Page - Field Description..............................................5-111
Table 5-53. Device Configuration Page - Field Descriptions........................................5-113
Table 5-54. Medium Partition Page - Field Descriptions .............................................5-116
Table 5-55. PREVENT/ ALLOW MEDIUM REMOVAL Command Descriptor Block –
Field Descriptions...................................................................................5-120
Table 5-56. READ Command Descriptor Block - Field Descriptions ..............................5-122
Table 5-57. READ BLOCK LIMITS Data - Field Descriptions .........................................5-126
Table 5-58. READ BUFFER Command Descriptor Block - Field Descriptions...................5-128
Table 5-59. READ BUFFER Header - Field Descriptions ................................................5-129
Table 5-60. READ POSITION Command Descriptor Block - Field Descriptions ...............5-131
Table 5-61. READ POSITION Data - Field Description..................................................5-133
Table 5-62. RECEIVE DIAGNOSTIC RESULTS Command Data – Field Descriptions..........5-135
Table 5-63. RELEASE UNIT Command Data - Field Descriptions..................................5-138
Table 5-64. REPORT LUNS Command Data - Field Descriptions ..................................5-139
Table 5-65. REQUEST SENSE Command Data - Field Descriptions................................5-141
Table 5-66. REQUEST SENSE Data - Field Descriptions................................................5-143
Table 5-67. Supported Sense Keys ...........................................................................5-146
Table 5-68. Supported ASC / ASCQ in Hex................................................................5-147
Table 5-69. RESERVE UNIT Command - Field Descriptions...........................................5-151
Table 5-70. REWIND Command Data - Field Descriptions............................................5-153
Table 5-71. SEND DIAGNOSTIC Command - Field Descriptions....................................5-155
Table 5-72. SEND DIAGNOSTIC CDB Bits Selftest, DevOfl, and UnitOfl ........................5-157
Table 5-73. SEND DIAGNOSTIC Parameter List – Field Descriptions .............................5-158
Table 5-74. Sense Keys Used for SEND DIAGNOSTIC ..................................................5-159
Quantum DLT 4000 Tape Drive xvii
Table of Contents
Table 5-75. ASC / ASCQ for SEND DIAGNOSTIC .........................................................5-159
Table 5-76. SPACE Command Data - Field Descriptions..............................................5-161
Table 5-77. VERIFY Command Data - Field Descriptions..............................................5-166
Table 5-78. WRITE Command Data - Field Descriptions ..............................................5-168
Table 5-79. WRITE BUFFER Command Data - Field Descriptions...................................5-170
Table 5-80. WRITE FILEMARKS Command Data - Field Descriptions.............................5-174
Table A-1. Internal Status Codes............................................................................. A-1
Table A-2. Internal Status Bit Flags.......................................................................... A-4
Table B-1. Bugcheck Packet Error Codes (Bytes 9 - 10) ............................................. B-2
Table B-2. Event Log Error Codes (Bytes 9 – 10)....................................................... B-3
Table B-3. Directory Failure Event Package – Field Descriptions ................................ B-5
Table C-1. Block Size Used for Firmware Update Type.............................................. C-2
Table C-2. Results of Firmware Update ................................................................... C-5
Table D-1. Write-Protect Switch Positions................................................................ D-9
Table D-2. When to Use a Cleaning Tape Cartridge ................................................. D-12
xviii Quantum DLT 4000 Tape Drive
REVISION HISTORY
This Revision History provides a concise publications record of this manual. It lists the manual’s revision levels, release dates, and a summary of changes for each release.
Manual Number
- Revision Level
81-108336-01 May 5, 1995 Original issue
81-108336-02 Caution added for unloading a tape cartridge
81- 60043- 01 March 10, 1996
Date of Release Summary of Changes
Part number 81-108336-02 obsoleted Manual-wide, trademark copyrights, and other changes. Fast Data Transfer Rate correction. Figure 2-1 and 3-6 corrected. Section E added to POST testing. Table 3-2 corrected. Description of tape cartridge corrected. Notes added to Loading a Cartridge section. Added a caution to Unloading a Cartridge section. Chapter 4 rewritten. POST description updated. Figure 5-2 updated, page 5-6. Table 5-1 updated, page 5-11. Table 5-2 updated, page 5-14. Table 7-1 added, page 7-4. Table 7-1 consolidated, page 7-8. Caution message added, page 7-9. Table 8-1 modified, page 8-8. Table 8-2 modified, page 8-15. Table 8-6 modified, page 8-21. Product Family description and table added, page 8-22. Density Code updated, page 8-49. Table 8-3, additions and modifications, pages 8-65 and 8-67. Tables A-1, A-5, A-8, A-9, A-10, A-12, A-14, A-16, A-17, A-20, and A30 changed (pages A-3, A-1, A-13, A-14, A-15, A-17, A-18, A-23).
Quantum DLT 4000 Tape Drive
xix
Revision History
Manual Number
- Revision Level
81-60043-02 April 08, 1999 Entire manual rewritten to conform to corporate standard for product
81-60043-03 September 18, 2000 Revised.
81-60043-04 April 4, 2001 Updated corporate address and reader comment address.
81-60043-04 A02 November 10, 2003 Changed Service Center contact number from (800) 826-8022 to
Date of Release Summary of Changes
manuals. Manual updated to include new version of the DLT4000 tape drive (Chapters 1 and 2); SCSI command updates (Chapter 5); consolidation of Request Sense ASC/ASCQ codes into one complete table (Chapter 5) and tape cartridge additions (Appendix D).
Chapter 2: Pinout tables corrected for 50-pin single-ended and differential SCSI connector signals (Tables 2-2 and 2-3).
Chapter 5: Corrections made to LOG SENSE command’s DEVICE STATUS page (Log Parameter Format and TSD, ClnQ, and ClnR bits).
Appendix A: Changed field descriptions in Table A-2.
(888) 827-3378 per ECO C008218.
xx
Quantum DLT 4000 Tape Drive
ABOUT THIS MANUAL
“About this Manual” outlines the scope and contents of this manual. It contains information about the intended audience, purpose of the manual, document organization, and document conventions.
AUDIENCE
This manual is written for original equipment manufacturers (OEMs) that are
integrating the Quantum DLT4000 tape drive and into a system or subsystem.
Its primary audience is the OEM technical staff that makes tape drive purchase and configuration decisions, and system integrators that are responsible for the SCSI interface. Additionally, the manual can be used by technically astute end­users for installation and operation of the tape drive, although that is a secondary audience.
PURPOSE
This manual describes the rackmount and tabletop versions of the DLT 4000 tape drive. It is intended to provide the information necessary to integrate the tape drive into a computer system or subsystem.
DOCUMENT ORGANIZATION
This product manual contains five chapters, a number of appendixes of related useful information, and an index. It includes an overview of the Small Computer System Interface (SCSI) and detailed descriptions of the messages and SCSI commands as used by the tape drive. The manual is organized as follows:
Chapter 1 General Description and Specifications
This chapter contains a brief description of and specifications for the drive.
Quantum DLT 4000 Tape Drive xxi
About This Manual
Chapter 2 Hardware Implementation
This chapter contains configuration and installation information for the tape drive, descriptions of the drive controls and LEDs, and information on running the self-test.
Chapter 3 SCSI Description
This chapter provides a detailed description of the logical interfaces of the tape drive. It describes the products’ compliance with the ANSI SCSI-2 specification. The drive’s many optional features are described here and throughout the manual.
Chapter 4 Messages
This chapter provides a list and description of most messages supported by the tape drive. The SCSI message system allows communication between SCSI initiators and SCSI targets (the tape drive, in this case) for interface management and for command elaboration and qualification.
Chapter 5 SCSI Commands
This chapter describes in detail each command supported by the tape drive. The SCSI command system enables an initiator to direct a tape drive to perform a wide range of operational and diagnostic functions. This chapter also provides sense key information for the REQUEST SENSE SCSI command.
Appendix A Definition of Vendor Unique Sense Data Information
Appendix A provides a list of internal status codes related to the REQUEST SENSE SCSI command.
Appendix B EEPROM-Resident Bugcheck and Event Logs
Appendix B provides an explanation of the error and event logs stored in semi-permanent, non-volatile memory.
Appendix C Updating the Firmware
Appendix C provides a step-by-step procedure for updating a tape drive’s PCBA controller-resident firmware.
Quantum DLT 4000 Tape Drivexxii
About This Manual
Appendix D The Tape Cartridge
Appendix D provides tape cartridge handling and inspection procedures, information on the write-protect switch, how to load and unload a tape cartridge, and how to use a cleaning tape cartridge.
CONVENTIONS
This manual uses the following conventions to designate specific elements:
Element Convention Example
Commands Uppercase (unless case-sensitive) FORMAT UNIT
Messages Uppercase INVALID PRODUCT NUMBER
Hexadecimal Notation Number followed by lowercase h 25h
Binary Notation Number followed by lowercase b 101b
Decimal Notation Number without suffix 512
Acronyms Uppercase POST
Abbreviations Lowercase, except where standard
usage requires uppercase
READER COMMENTS
Quantum is committed to providing the best products and service. Our manuals are important components of our products. We encourage your comments, suggestions, and corrections for this manual. Please send all comments to:
Quantum Technical Publications 4001 Discovery Drive, Suite 1100 Boulder, CO 80303
Quantum DLT 4000 Tape Drive xxiii
Mb (megabits) MB (megabytes)
About This Manual
Quantum DLT 4000 Tape Drivexxiv
Chapter 1
GENERAL DESCRIPTION AND SPECIFICATIONS
This chapter provides a description and gives specifications for the Quantum DLT™4000 Tape Drive.
1.1 PRODUCT DESCRIPTION
The Quantum DLT 4000 tape drive is a high-performance, high-capacity,
streaming cartridge tape product designed for efficient data back-up for midrange and high-end computing systems. With Quantum’s DLT advanced linear recording technology and a precision tape guide system, the drive is ideally suited for high-end workstation, server, and network backup requirements.
Using data compression, the DLT 4000 tape drive features a formatted capacity of 40.0 GB* and a sustained user data transfer rate of 3.0 MB/second* (native capacity is 20.0 GB; native data transfer rate is 1.5 MB/second).
The device is an extended-length, 5.25-inch form factor, half-inch cartridge tape drive. The design includes a two-channel read/write head, Lempel-Ziv (LZ) high-efficiency data compression, and tape mark directory to maximize data throughput and minimize data access time.
The tape drive is available in rackmount (Figure 1-1) or tabletop (Figure 1-2) form. The tabletop versions of the drive are packaged in a housing that includes its own cooling fan and power supply, requiring ac power.
Quantum DLT 4000 Tape Drive 1-1
General Description and Specifications
Figure 1-1 Quantum DLT 4000 Tape Drive (Rackmount)
Tabletop Version 1
Figure 1-2 Quantum DLT 4000 Tape Drive (Tabletop)
1-2 Quantum DLT 4000 Tape Drive
Tabletop Version 2
1.2 PRODUCT FEATURES
The DLT 4000 tape drive offers the following product features:
20.0 GB Native, 40.0 GB Compressed Capacity (Formatted capacity
assuming a 2:1 data compression ratio. Note that actual compression ratio
depends on the type of data, SCSI bus limitations, and system
configuration.)
Superior Error Detection and Correction
Extensive Embedded Diagnostic/Self-Test Software
Tape-Loadable Firmware
1.3 PRODUCT SPECIFICATIONS
The following subsections contain full specifications for the Quantum DLT 4000
tape drive. Specifications for the DLTtape tape media cartridges are also
included.
1.3.1 Physical Specifications
The following table provides physical dimensions for the DLT 4000.
General Description and Specifications
Table 1–1 DLT 4000 Physical Dimensions
Dimension Rackmount Tabletop
(Version 1)
Height 3.25 in. (8.26 cm) without front
bezel; 3.40 in (8.64 cm) with front bezel.
Width 5.70 in. (14.48 cm) behind front
bezel; 5.84 in (14.83 cm) with front bezel.
Depth 9.00 in. (22.86 cm) measured from
back of front bezel; 9.60 in. (24.38
cm) including front bezel Typical Weight: 6 lb., 7 oz (2.9 kg) (14 lb., 9 oz) 6.63 kg
Note: Mounting hole pattern for the bottom and sides of the drive is industry standard.
5.77 in.
(14.66 cm)
9.25 in.
(23.50 cm)
13.08 in.
(33.22 cm)
Tabletop
(Version 2)
4.88 in.
(12.40 cm)
9.06 in.
(23.01 cm)
12.60 in.
(32.00 cm)
Quantum DLT 4000 Tape Drive 1-3
General Description and Specifications
1.3.2 Interface Type
DLT 4000 tape drives are available with narrow SCSI-2 fast single-ended or differential high voltage interfaces.
1.3.3 Storage Capacity
The following table provides the ranges of capacity (native and compressed) for the tape drive, depending on which DLTtape cartridge is used.
Table 1–2 DLT 4000 Storage Capacity
DLTtape Cartridge (Length of Medium)
DLTtape IV
(extended 1780 foot tape)
DLTtape IIIxt
(extended 1780 foot tape)
DLTtape III
(standard 1167 foot tape)
Note: A compression factor of 2:1 can be attained, depending on the data type and
subject to the limitations of the SCSI bus design and the configuration of the system in which the tape drive is installed.
Native
Storage Capacity
20.0 GB User Data
15.0 GB User Data
10.0 GB User Data
Compressed
Storage Capacity
40.0 GB User Data
(compressed 2:1)
30.0 GB User Data
(compressed 2:1)
20.0 GB User Data
(compressed 2:1)
1.3.4 Performance Data
The following table provides performance data for the DLT 4000 tape drive.
Table 1–3 DLT 4000 Performance Data
Feature Description
Transfer Rate, User Native Transfer Rate, Raw Native Transfer Rate, Compressed *
Error Rates Recoverable READ Error Rate = 1 in 1x107
* = Depending on data type and SCSI bus limitations/system configuration. Note that data is typical; times may be longer if error recovery time is needed.
1.5 MB/second 2.5 MB/second More than 3.0 MB/second maximum write, 10 MBburst mode; More than 2.5 MB/second maximum read, 10 MBburst mode
Recoverable WRITE Error Rate = 1 in 1x10 Uncorrected Error Rate = 1 in 1x1017 bits read Undetected Error Rate = 1 in 1x1027 bits read
6
1-4 Quantum DLT 4000 Tape Drive
General Description and Specifications
Table 1–3 DLT 4000 Performance Data (continued)
Feature Description
Tracks 128; 64 pairs Linear Bit Density 81,600 bpi per track READ / WRITE Tape Speed 98 inches/second Rewind Tape Speed 150 inches/second Linear Search Tape Speed 150 inches/second Average Rewind Time 70 seconds Maximum Rewind Time 140 seconds Average Access Time (from BOT) 45 seconds Maximum Access Time (from BOT) 90 seconds Load to BOT (typical) 48 seconds - previously written (slightly longer if using
a blank tape)
Load to BOT (max time using V120 firmware or greater)
Unload from BOT 17 seconds Nominal Tape Tension 3.0 +/- 1 oz when stationary; 4.7
* = Depending on data type and SCSI bus limitations/system configuration Note that data is typical; times may be longer if error recovery time is needed.
5.2 minutes with blank tape that fails calibration (time includes calibration retries)
+/- 1 oz at operating speed
1.3.5 Environmental Specifications
The following table lists operating and non-operating environmental specifications for the DLT 4000 tape drive.
Table 1–4 DLT 4000 Environmental Specifications
Specification Operating Limits Non-Operating Limits
(Power On; No Tape Loaded)
Wet Bulb Temperature 25°C (77°F) 25°C (77°F) Dry Bulb Temperature
Range Temperature Gradient 11°C (52°F) /hour (across range) 15°C (59°F) /hour (across range) Temperature Shock 10°C (50°F) (over two minutes) 15°C (59°F) (over two minutes) Relative Humidity 20 to 80% (noncondensing) 10 to 95% (noncondensing)
Humidity Gradient 10% / hour 10% / hour
10°C to 40°C (50°F to 104°F) -40°C to 66°C (-40°F to 151°F)
Quantum DLT 4000 Tape Drive 1-5
General Description and Specifications
Table 1–4 DLT 4000 Environmental Specifications (continued)
Specification Operating Limits Non-Operating Limits
(Power On; No Tape Loaded)
Altitude Normal pressure from -500 feet to
30,000 feet
Airflow Velocity 125 linear feet per minute
measured directly in front of the front bezel
Shock 5 G peak, half-sine; 11 ms
duration; 10 G each direction of each axis, 35 sec between shocks, 60 shocks total; 3 axes
Vibration 5 to 500 Hz @ 0.25 G; sweep rate
=1 octave per minute
See Table 1-5
See Table 1-6
Table 1–5 DLT 4000 Non-Operating Shock Specifications
Description Rackmount and Tabletop
Shock (Unpackaged) 40 G, 10 ms, square wave;
140 G, 2 ms, half-sine; X,Y,Z axes, twice in each axis, total of 6 shocks.
Shock (Packaged) Drop: 42
inches (items < 20.0 lbs.) 16 drops total
Table 1–6 DLT 4000 Non-Operating Vibration Specifications
Description Rackmount and Tabletop
Sine (Unpackaged) 1-500-10 Hz; 1 G acceleration level; X,Y,Z axes, sweep rate =½
octave/minute
Random (Unpackaged) 5-500 Hz; 2 G acceleration level; X,Y,Z axes, sweep rate = 60
min/axis
Random (Packaged) Power Spectral Density
(Vertical)
5 to 10 Hz 10 to 50 Hz 50 to 300 Hz
0.003 G2/Hz @ 5, to 0.020 @ 10 Flat @ 0.020 G2/Hz
0.020 G2/Hz @ 50 with 8 dB/octave rolloff
1-6 Quantum DLT 4000 Tape Drive
Table 1–6 DLT 4000 Non-Operating Vibration Specifications (continued)
Description Rackmount and Tabletop
Power Spectral Density (Horizontal)
5 to 10 Hz 10 to 50 Hz 50 to 200 Hz Each of the X, Y, and Z axes for one hour (3 hours total)
1.3.6 Power Requirements
The following table provides the applicable power requirements for rackmount and tabletop versions of the DLT 4000 tape drive. Note that the tabletop DLT 4000 requires ac power.
Table 1–7 DLT 4000 Power Requirements
Requirement Rackmount Tabletop
Electrical Rating (Auto Ranging) Not Applicable 100 to 240 VAC Power Requirements 25 W, steady state;
27 W, maximum Power Consumption: +5 V (±5%) bus * 2.0 A, steady state;
2.5 A, maximum
+12 V (±5%) bus * 0.8 A, steady state;
1.5 A, maximum
* = Voltage measured at the power bus connector pins.
General Description and Specifications
0.0011 G2/Hz @ 5, to 0.007 @ 10 Flat @ 0.007 G2/Hz
0.007 G2/Hz @ 50 with 8 dB/octave rolloff
50 W, maximum
Not applicable
Not applicable
1.3.7 Electromagnetic Emissions
The rackmount version of the drive complies with FCC Class A in a standard enclosure; the tabletop version complies with the FCC Class B limits.
Quantum DLT 4000 Tape Drive 1-7
General Description and Specifications
1.3.8 EMI and Safety Certifications
Table 1−8 provides the certifications held by the rackmount and tabletop versions of the tape drive. Table 1−9 provides the safety certification held by the
tape drives.
Table 1–8 EMI Emission Certificates
Rackmount Tabletop
CEmark Class A VCCi Class 1 CISPR 22 Class A FCC Class A Devices
Table 1–9 Safety Certifications
Rackmount and Tabletop
UL CSA
TÜV “BG”
MARK IEC
CEmark Class B VCCi Class 2 CISPR 22 Class B FCC Class B Devices
1.3.9 Reliability (Projected)
Mean time between failures (MTBF) for the tape drive is projected to be 200,000 hours at 100% duty cycle. Head life is 10,000 tape motion hours.
Media durability is projected to be 1,000,000 passes of the tape medium across the read/write heads (15,000 uses).
Quantum Corporation does not warrant that predicted MTBF is representative of any particular unit installed for customer use. Actual figures vary from unit to unit.
1-8 Quantum DLT 4000 Tape Drive
General Description and Specifications
1.3.10 Acoustic Noise Emissions
The following tables provide the tape drive’s acoustic noise emission levels, both as noise power and sound pressure. Information about acoustic emissions is also provided in German to fulfill an international requirement.
Table 1-10 Acoustic Noise Emissions, Nominal (English)
Acoustics – Preliminary declared values per ISO9296 and ISO 7779/EN27779
Noise Power Emission Level Sound Pressure Level (LNPEc) (LPAc) Product Idle Streaming Idle Streaming Rackmount Not applicable Not applicable Not applicable Not applicable Tabletop 4.6 B 5.1 B 30.0 dB 41.0 dB [Current values for specific configurations are available from Quantum representatives.
1B = 10 dBA.]
Table 1-11 Acoustic Noise Emissions for German Noise Declaration Law
Schallemissionswerte - VorläufigeWerteangaben nach ISO 9296 und ISO
7779/DIN EN27779:
Schalleistungspegel Schalldruckpegel LwAd, B LpAm, dBA (Zuschauerpositionen) Gerfdt Leerauf Betrieb Leerauf Betrieb Rackmount N/A 5,5 B N/A 45,0 B Tabletop 5,2 B 5,3 B 39,0 dB 40,0 dB [Aktuelle Werte für spezielle Ausrüstungsstufen sind über die Quantum Equipment
Vertretungen erhältlich. 1 B = 10 dBA]
1.3.11 Tape Drive Recording Type
The tape drive uses 2 - 7 RLL code with DLT 2000, DLT 2000xt, or DLT 4000 formats; MFM with 2.6 GB / 6.0 GB DLT 260 and DLT 600 formats.
Quantum DLT 4000 Tape Drive 1-9
General Description and Specifications
1.3.12 DLTtape Recording Media Specifications
The following table provides specifications for tape media.
Table 1-12 DLTtape Media Specifications
DLTtape Media Type
DLTtape III Width: 0.5 in., metal particle
DLTtape IIIxt Width: 0.5 in., metal particle
DLTtape IV Width: 0.5 in., metal particle
Specifications
Length: 1200 feet (standard 1167 ft. tape) Cartridge Dimensions: 4.1 in x 4.1 in x 1.0 in Shelf Life: 30 years min. @ 20°C & 40% RH (non-condensing) Usage: 1,000,000 passes (typical office/computer environment)
Length: 1800 feet (extended 1780 ft tape) Cartridge Dimensions: 4.1 in x 4.1 in x 1.0 in Shelf Life: 30 years min. @ 20°C & 40% RH (non-condensing) Usage: 1,000,000 passes (typical office/computer environment)
Length: 1800 feet (extended 1780 ft. tape) Cartridge Dimensions: 4.1 in x 4.1 in x 1.0 in Shelf Life: 30 years min. @ 20°C & 40% RH (non-condensing) Usage: 1,000,000 passes (typical office/computer environment)
1-10 Quantum DLT 4000 Tape Drive
Chapter 2
HARDWARE IMPLEMENTATION
This chapter describes how to install the internal tape drive or “brick” into a rackmount system. This includes configuration jumper settings, connector pin assignments, installation instructions, power and signal cabling descriptions, and operating instructions. This chapter also includes information on configuring and connecting the tabletop version of the drive into a system.
This chapter covers the following topics:
Safety, Handling and Electrostatic Discharge (ESD) Protection (Section 2.1)
describes appropriate guidelines when working with the tape drive.
Drive Setup (Section 2.2) describes how to set up the tape drive for SCSI ID,
TERMPWR, and parity checking.
Drive Installation (Section 2.3) describes how to mount and install the tape
drive into the system.
Drive Connections (Section 2.4) identifies the connectors on the tape drive
including the SCSI, power and optional loader connectors.
Drive Controls and Light Emitting Diodes (LED’s) (Section 2.5) identifies
the front panel controls and LED’s and describes their functionality. It also explains density selection.
Power On Self Test (POST) (Section 2.6) describes the activities that occur
when power is first applied to the drive.
Troubleshooting (Section 2.7) lists troubleshooting tips in the event that the
tape drive fails.
2.1 SAFETY, HANDLING AND ELECTROSTATIC DISCHARGE (ESD) PROTECTION
Inappropriate or careless handling of tape drives may result in damage to the product. Follow the precautions and directions to prevent damaging the tape drive.
Quantum DLT 4000 Tape Drive 2-1
Hardware Implementation
2.1.1 Safety Precautions
For your safety, follow all safety procedures described here and in other sections of the manual.
Remove power from the computer system (or expansion unit) before
installing or removing the tape drive to prevent the possibility of electrical shock or damage to the tape drive. Unplug the unit that contains or is to contain the drive from ac power to provide an added measure of safety.
Read, understand, and observe any and all label warnings.
2.1.2 Handling
Damage to the drive can occur as the result of careless handling, vibration, shock, or electrostatic discharge (ESD). Always handle the tape drive with care to avoid damage to the precision internal components.
Follow these guidelines to avoid damage to the drive:
Always observe prescribed ESD precautions.
Keep the drive in its anti-static bag until ready to install.
Always use a properly fitted wrist strap or other suitable ESD protection
when handling the drive.
Hold drive only by its sides. Do not touch any components on the PCBA.
Always handle the drive carefully and gently. A drop of ¼ inch onto a bench
or desktop may damage a drive.
Do not bump, jar, or drop the drive. Use care when transporting the drive.
Always gently place the drive flat, PCB side down, on an appropriate ESD-
protected work surface to avoid the drive being accidentally knocked over.
Do not pack other materials with the drive in its anti-static bag.
Place the drive in the anti-static bag before placing it in a shipping
container.
Do not stack objects on the drive.
Do not expose the drive to moisture.
Do not place hands or foreign objects inside the tape drive’s door/receiver
area.
2-2 Quantum DLT 4000 Tape Drive
Hardware Implementation
2.1.3 Electrostatic Discharge (ESD) Protection
Various electrical components on/within the tape drives are sensitive to static electricity and Electrostatic Discharge (ESD). Even a static buildup or discharge that is too slight to feel can be sufficient to destroy or degrade a component's operation.
To minimize the possibility of ESD-related damage to the drive, we strongly recommend using both a properly installed workstation anti-static mat and a properly installed ESD wrist strap. When correctly installed, these devices reduce the buildup of static electricity that might harm the drive.
Observe the following precautions to avoid ESD-related problems:
Use a properly installed anti-static pad on your work surface.
Always use a properly fitted and grounded wrist strap or other suitable ESD
protection when handling the drive and observe proper ESD grounding techniques.
Hold the drive only by its sides. Do not touch any components on the
PCBA.
Leave the drive in its anti-static bag until you are ready to install it in the
system.
Place the drive on a properly grounded anti-static work surface pad when it
is out of its protective anti-static bag.
Do not use the bag as a substitute for the work surface anti-static pad. The
outside of the bag may not have the same anti-static properties as the inside. It could actually increase the possibility of ESD problems.
Do not use any test equipment to check components on the PCBA. There are
no user-serviceable components on the drive.
2.2 DRIVE SETUP
Drive setup for DLT 4000 tape drive includes the following:
Set the SCSI ID for the drive (default = SCSI ID 5)
Configure the drive to provide TERMPWR
Set parity checking for the drive (default = parity checking enabled)
If you want to change any of the settings, go to the applicable subsection; otherwise, proceed directly to section 2.3.
Quantum DLT 4000 Tape Drive 2-3
Hardware Implementation
129
2.2.1 Set the Rackmount Drive SCSI ID
Each device on the SCSI bus must have a unique SCSI ID address assigned to it. For specific recommendations for assigning SCSI IDs, refer to the system or SCSI controller documentation.
Rackmount drives can be configured for SCSI ID addresses that range from 0 to 7 (default=5) in one of two ways:
a) jumper the 10-pin SCSI ID jumper block shown in Figure 2-1, or b) set the IDs through firmware. If the firmware is set to SCSI ID = 5, then no
jumpers are installed on the SCSI ID jumper block.
This subsection discusses setting the SCSI ID on the rackmount drive via the jumper block. Table 2-1 lists the SCSI ID address and jumper settings.
NOTES
The default setting for the tape drive is SCSI ID 5; the host adapter is typically SCSI ID 7.
A jumper must be installed across Pins 9-10 (Remote ID Present pins) for the host to recognize any SCSI ID selections from this jumper block.
SCSI ID Jumper Block (J13)
10
(default SCSI ID 5 shown)
Figure 2-1 DLT 4000 SCSI ID Jumper Location (Rackmount Version Shown)
2-4 Quantum DLT 4000 Tape Drive
Front Panel
Loader Connector (J12)
Hardware Implementation
Table 2-1 SCSI ID Address Selections
SCSI ID Jumper Across Pins:
9-10 7-8 5-6 3-4 1-2
0 1 0 0 0 0 1 1 0 0 0 1 2 1 0 0 1 0 3 1 0 0 1 1 4 1 0 1 0 0
5 (default) 1 0 1 0 1
6 1 0 1 1 0 7 1 0 1 1 1
0 = No Jumper installed 1 = Jumper installed
Quantum DLT 4000 Tape Drive 2-5
Hardware Implementation
1
1
252617
18
2.2.2 Configure the Rackmount Drive for TERMPWR (Single-Ended Only)
A SCSI bus must be terminated at each end of the bus. At least one device must supply terminator power (TERMPWR). Quantum recommends that every device on the SCSI bus be configured to supply TERMPWR to ensure that there is a sufficient level of voltage along the SCSI bus.
Install a jumper across Pins 3 and 4 (Figure 2-2) to enable TERMPWR.
Front Panel
ALDR (J26)
TERMPWR (J24)
Not used
Parity Check (J25)
2
Install Jumper on Pins 3-4 to enable TERMPWR.
Install Jumper on Pins 1-2 to disable Parity Checking.
Figure 2-2 DLT 4000 TERMPWR and Parity Check Jumper Locations (Rackmount
Version Shown)
2-6 Quantum DLT 4000 Tape Drive
2
Hardware Implementation
2.2.3 Configure The Rackmount Drive for Parity Checking
The default setting for DLT 4000 tape drives is to have parity checking enabled.
If the system to which you are configuring the rackmount tape drive does not generate SCSI parity, there are two ways that parity checking can be disabled. You can disable parity checking by:
(a) Installing a jumper across Pins 1 and 2 on the parity check connector as
shown in Figure 2-2, or
(b) Installing a jumper across Pins 7 and 8 on the SCSI ID jumper block shown
in Figure 2-1.
2.2.4 Configure the Tabletop Drive
Figures 2-3 and 2-4 show the locations of the controls for the tabletop versions of the drive. Note that these drives are normally configured to meet customer specifications before they leave the factory so should not require any internal configuration changes on-site.
Figure 2–3 Tabletop (Version 1) Back Panel Controls
Quantum DLT 4000 Tape Drive 2-7
SCSI ID Pushbutton
Hardware Implementation
SCSI Signal Connector (IN)
SCSI ID Pushbutton
Power Switch
SCSI Signal Connector (Out/Termination)
Figure 2–4 Tabletop (Version 2) Back Panel Controls
SCSI ID - The SCSI ID default for the tabletop drive is set to 5; the drive can be configured for SCSI ID addresses that range from 0 to 7 using the SCSI ID pushbutton. Press the button above or below the ID number display to set the desired SCSI ID. The top button increases the ID number; the bottom button decreases the ID number.
TERMPWR and/or Parity Check - The tabletop version of the drive can be internally configured to supply TERMPWR or parity checking. Contact your service representative if you want to change either of these settings on the tabletop version of the drive.
2.3 DRIVE INSTALLATION
This section describes how to mount and secure the drive in the system. Figure 2–
5 shows the mounting locations and dimensions for the drive.
Power Connector
2-8 Quantum DLT 4000 Tape Drive
9.60 (24.38)
9.00 (22.86)
Hardware Implementation
3.25
(8.26)
0.82
(2.08)
5.70
(14.48)
5.50
(13.97)
3.13
(7.94)
Side View - Inches (Centimeters)
9.60 (24.38)
1.88
(4.76)
3.40
(8.64)
Front Panel
5.84
(14.83)
0.10
(0.25)
3.13
(7.94)
Bottom View - Inches (Centimeters)
1.88
(4.78)
Figure 2–5 Rackmount Drive Mounting Locations – Side and Bottom Views
Quantum DLT 4000 Tape Drive 2-9
Front Panel
Hardware Implementation
DLT 8000 Library
Drive Side
In some systems, it may be more convenient to connect the SCSI bus and power cables to the drive before securing it in the system.
Because of the variety of mounting possibilities for tape drive, the instructions presented here are general in nature. They should be used only as a guide for mounting the drive in your system.
Mount the drive in the system by performing the following steps:
1. Position the drive in the system and align the drive mounting holes (side or bottom) with those in the system.
2. Using four (4) screws, secure the tape drive in its bay or chassis. Note that screws used to mount the tape drive must be 8 x 6-32 UNC-2B screws. There is no danger of these screws touching electronic components or otherwise damaging the tape drive.
2.4 DRIVE CONNECTIONS
The following warning applies to the bezel connector located under the front panel of the tape drive. This connector is an internal connector so is not discussed in detail in this manual.
WARNING
The bezel connector pinout on the DLT 4000 tape drive (Model TH5XB-NP) is not compatible with any other DLT products. A flex cable adapter is available to connect these tape drives to a library/loader system that uses header pins for the bezel connection. Do not use this flex cable adapter to connect to drives other than the Model TH5XB-NP. The following label has been applied to the drive to warn the user when making this connection:
WARNING
°
DLT 4000
DLT 7000 Library
2-10 Quantum DLT 4000 Tape Drive
Hardware Implementation
Pin 1
Pin 1
Drive Back
The three external connectors on the DLT 4000 tape drive that are discussed in this manual are the SCSI, power and optional loader connectors. Tabletop connectors are described in subsection 2.4.3.
2.4.1 SCSI and Power Connectors (Rackmount)
Figure 2-6 shows the pin orientation for the 50-pin SCSI connector and 4-pin power connector located on the back of the tape drive. Pin assignments for the single-ended and differential SCSI connectors are listed in Tables 2–2 and 2-3; pin assignments for the power connector are listed in Table 2-4.
Align the appropriate SCSI and power cables to their matching connectors. Carefully connect the cables, to avoid bending or damaging the connector pins.
Optional Power Connector
SCSI-2 Connector
4-Pin Power Connector
(Not used)
Figure 2-6 SCSI and Power Cable Connectors (Rackmount Version Shown)
Quantum DLT 4000 Tape Drive 2-11
Hardware Implementation
Table 2–2 Single-Ended SCSI Pin Assignment
Signal Name Pin Number Pin Number Signal Name
Ground 1 2 -DB(0)
Ground 3 4 -DB(1)
Ground 5 6 -DB(2)
Ground 7 8 -DB(3)
Ground 9 10 -DB(4)
Ground 11 12 -DB(5)
Ground 13 14 -DB(6)
Ground 15 16 -DB(7)
Ground 17 18 -DB(P)
Ground 19 20 Ground
Ground 21 22 Ground
Reserved 23 24 Reserved
Open 25 26 TERMPWR
Reserved 27 28 Reserved
Ground 29 30 Ground
Ground 31 32 -ATN
Ground 33 34 Ground
Ground 35 36 -BSY
Ground 37 38 -ACK
Ground 39 40 -RST
Ground 41 42 -MSG
Ground 43 44 -SEL
Ground 45 46 -C/D
Ground 47 48 -REQ
Ground 49 50 -I/O
Note: The minus sign (-) next to a signal indicates active low.
2-12 Quantum DLT 4000 Tape Drive
Hardware Implementation
Table 2–3 Differential SCSI Pin Assignment
Signal Name Pin Number Pin Number Signal Name
Open 1 2 Ground
DB(0) 3 4 -DB(0)
DB(1) 5 6 -DB(1)
DB(2) 7 8 -DB(2)
DB(3) 9 10 -DB(3)
DB(4) 11 12 -DB(4)
DB(5) 13 14 -DB(5)
DB(6) 15 16 -DB(6)
DB(7) 17 18 -DB(7)
DB(P) 19 20 -DB(P)
DIFFSENS 21 22 Ground
Ground 23 24 Ground
TERMPWR 25 26 TERMPWR
Ground 27 28 Ground
ATN 29 30 -ATN
Ground 31 32 Ground
BSY 33 34 -BSY
ACK 35 36 -ACK
RST 37 38 -RST
MSG 39 40 -MSG
SEL 41 42 -SEL
C/D 43 44 -C/D
REQ 45 46 -REQ
I/O 47 48 -i/O
Ground 49 50 Ground
Quantum DLT 4000 Tape Drive 2-13
Hardware Implementation
Table 2–4 4-Pin Power Connector Pin Assignment
Pin Number Signal Name
1 +12 VDC 2 Ground (+12 V return) 3 Ground (+5 V return) 4 +5 VDC
2.4.2 Optional Loader Connector (Rackmount)
The loader connector provides signals to be used when the tape drive is part of a loader/library configuration. Figure 2-7 shows the location of the connector.
Front Panel
SCSI ID Jumper Block (J13)
Figure 2–7 Loader Connector Block Location (Rackmount Version Shown)
2-14 Quantum DLT 4000 Tape Drive
10-Pin Loader Connector (J12)
Hardware Implementation
2.4.3 Tabletop Drive Connectors
Figures 2-8 and 2-9 show the locations of the connectors for the tabletop version of the drive.
SCSI ID Pushbutton
Figure 2–8 Tabletop (Version 1) Back Panel Connectors
Quantum DLT 4000 Tape Drive 2-15
Hardware Implementation
SCSI Signal Connector (IN)
SCSI ID Pushbutton
Power Switch
SCSI Signal Connector (Out/Termination)
Figure 2–9 Tabletop (Version 2) Back Panel Connectors
Align the appropriate SCSI and power cables to their matching connectors. Carefully connect the cables and avoid bending or damaging the connector pins.
1. Make sure the power switch is in the off (0) position.
2. Connect one end of the SCSI cable to the SCSI IN connector on the back
panel of the drive. Connect the other end of the SCSI cable to the SCSI connector on your system, or for daisy-chained configurations, to another SCSI device.
3. Snap the wire cable clamps into place to secure the cables.
4. Be sure to terminate the SCSI bus. If the tabletop drive is the last or only
device on the bus, terminate the bus by connecting the SCSI terminator to the SCSI OUT connector on the back of the drive. Depending on the terminator supplied, snap the wire cable clamps into place or tighten the screws to secure the terminator.
If the tabletop drive is not the last or only device on the bus, install a terminator on the last device on the SCSI bus.
5. Connect one end of the power cord to the power connector on the back of the
drive. Connect the other end of the cord to the ac outlet.
Power Connector
2-16 Quantum DLT 4000 Tape Drive
2.5 DRIVE CONTROLS AND LIGHT EMITTING DIODES (LEDS)
Density Override LED
This section identifies the front panel controls and LED’s and describes their functionality. It also explains density selection.
2.5.1 Front Panel Controls and LED’s
This section describes the front panel controls and Light Emitting Diodes (LED’s) used to operate the tape drive; all controls and LED’s are located on the tape drive’s front panel. Figure 2-10 shows the locations of the controls and LED’s on the front panel.
In addition to the controls and LED’s, the tape drive also has an audible beeper that signals when the drive’s cartridge insert/release handle can be safely used. Use these controls and LED’s to operate the tape drive and monitor the tape drive’s activities.
Density LED’s
2.6
6.0
10.0/15.0
20.0
Hardware Implementation
Write-Protected LED
Tape In Use LED
Compress LED
Density Select Button
Use Cleaning Tape LED
Operate Handle LED
Unload Button
Cartridge Insert/Release
Figure 2-10 DLT 4000 Front Panel
Quantum DLT 4000 Tape Drive 2-17
Hardware Implementation
Table 2–5 LED Functionality
LED LED Color Description
Density -
2.6, 6.0,
10.0/15.0, 20.0
Compress Amber On = Compression mode enabled (compression only valid for
Density Override Amber On = Operator selected a density from the density Select
Write-Protected Orange On = Tape is Write-Protected
Tape In Use Amber Irregular Blinking = Tape is moving; the drive is calibrating,
Amber Refer to Table 2-6 and subsection 2.5.2.
10, 15, or 20 GB densities only).
Off = Compression mode disabled.
Blinking = Compress mode manually overridden by operator.
Button on the front panel.
Off = Density to be selected by the host (automatic).
Refer to subsection 2.5.2 for Density Select information.
Off = Tape is Write-Enabled
reading, writing, or rewinding the tape.
Regular Blinking = The tape is loading, unloading, or rewinding.
On = A cartridge is loaded in the tape drive, but the tape is not moving; the drive is ready for use. This may also mean no application is communicating with the tape drive’s controller, or that the application is communicating but is not delivering any command that impact tape motion.
2-18 Quantum DLT 4000 Tape Drive
Hardware Implementation
Use Cleaning Tape
Amber On = Tape drive needs cleaning or tape is bad.
Remains on after cleaning tape unloads = Cleaning tape attempted to clean the drive head, but the tape expired so cleaning was not done.
After cleaning, LED lights again when (data) tape cartridge is reloaded = Problem tape cartridge. Try another cartridge. If problem persists, contact service representative.
Off = Cleaning is complete or cleaning is unnecessary.
Appendix D has more information on cleaning tape usage.
Quantum DLT 4000 Tape Drive 2-19
Hardware Implementation
Table 2–5 LED Functionality (continued)
LED LED Color Description
Operate Handle Green On = Insert/Release handle can be operated.
Off = Do not operate Insert/Release handle.
Blinking = Close the Insert/Release handle and wait for Operate Handle LED to light steadily.
Table 2–6 Density LED Functionality
Density LED (Amber)
2.6 On = Tape is recorded in 2.6 GB format.
6.0 On = Tape is recorded in 6.0 GB format.
10.0 / 15.0 On = Tape is recorded in 10.0 GB (DLTtape III cartridge) / 15.0 GB (DLTtape
20.0 On = Tape is recorded in 20.0 GB (DLTtape IV cartridge) format.
Note that these LED’s operate only if the correct media is loaded in the drive. For example, the default density of a DLTtape IV cartridge is 20.0 GB; if you are using a DLTtape IV cartridge, the density must be set to 20.0 GB. If you set the density to a different setting, the LED’s do not light and the density function does not work properly.
Description
Blinking = Tape is being forced by operator to record in this density; 2.6 GB has been selected for a WRITE from BOT.
Blinking = Tape is being forced by operator to record in this density; 6.0 GB has been selected for a WRITE from BOT.
IIIxt cartridge) format.
Blinking = Tape is being forced by operator to record in this density, 10.0 GB / 15.0 GB has been selected for a WRITE from BOT.
Blinking = Tape is being forced by operator to record in this density, 20.0 GB has been selected for a WRITE from BOT.
2-20 Quantum DLT 4000 Tape Drive
Hardware Implementation
Table 2-7 Control Functionality
Control Description
Density Select Button Refer to subsection 2.5.2.
Unload Button Use the Unload button to unload the tape cartridge. When you
push the Unload button, the tape drive waits until any active writing of data to tape is completed, then begins its unload sequence.
The tape drive rewinds the tape medium back into the cartridge. The tape must be completely rewound and unloaded into the cartridge before the cartridge can be removed from the tape drive. A complete unload operation may take 17 seconds from Beginning of Tape (BOT).
Note that if the tape drive is in an error state (all LED’s on the right­hand side of the front panel are flashing), pushing the Unload button causes the tape drive to reset and unload the tape, if possible. The Operate Handle LED will be lit steady if this is possible.
Cartridge Insert/Release Handle
Audible Beeper A beeper sound indicates that the cartridge insert/release handle
Use the Cartridge Insert/Release Handle to load or eject a tape cartridge only when the tape drive’s Operate Handle LED is lit and after the beeper sounds its tone. Lift the handle to its open position, or lower it to its closed position.
can be safely operated. When the drive emits its single beep tone, verify that the green Operate Handle LED is lit steadily before opening the handle.
CAUTION: To prevent damage to the tape drive, never operate the insert/release handle unless the green Operate Handle LED is lit and you have heard the beep tone that signals that the tape drive’s handle can be opened.
Quantum DLT 4000 Tape Drive 2-21
Hardware Implementation
2.5.2 Selecting Density
This subsection describes the drive’s density select features.
CAUTION
If a prerecorded tape is reused and a WRITE from the beginning of tape (BOT) executes (No Append Write), any data already recorded on the tape will be lost. This includes density changes, since they occur only when writing from BOT.
NOTES
On all READ and all WRITE APPEND operations, the data density that already exists on the tape cartridge remains the density.
Default density of a DLTtapeTM III cartridge is 10.0 GB, native. The only optional selections for DLTtape III cartridges are 2.6 GB, 6.0 GB,
10.0 GB (compression OFF), or 20.0 GB (compression ON).
Default density of a DLTtape IIIxt cartridge is 15.0 GB, native (compression OFF), or 30.0 GB (compression ON). No other density is supported.
Default density of a DLTtape IV cartridge is 20.0 GB, native (compression OFF). A density of 40.0 GB is user-selectable. No other density is supported.
When writing from BOT, tape density may be changed by:
Using the Density Select Button on the front panel of the tape drive. Using
the Density Select Button always overrides density selection via the host.
Using the operating system to issue a density designation. In this case, the
amber Density Override LED on the tape drive’s front panel turns off, indicating an automatic or host density selection.
Native default density for the DLTtape IV is 20.0 GB. The only available
option is compression on or off.
2-22 Quantum DLT 4000 Tape Drive
Hardware Implementation
Selecting Density on the Tape Drive
To select density on the tape drive:
1. Load the tape cartridge into the tape drive. The amber Tape in Use LED
blinks while the tape loads and calibrates.
2. After calibration is complete, the Tape In Use LED remains steadily lit. The
appropriate tape density LED along the left edge of the drive’s front panel lights to indicate the tape’s prerecorded density (if any), such as 2.6 GB or
6.0 GB.
3. Use the tape drive’s density Select Button to select the desired density, if
different than that indicated by the lighted tape density LED. Density selection is inactive until a WRITE from BOT is issued. The controller retains the selected density until 1) the density selection is changed, or 2) the tape is unloaded.
Selecting Density via the Host over the SCSI Bus
1. Use the SCSI MODE SELECT command to indicate the desired density
(Chapter 5).
2. Write data to the tape from BOT.
For Example:
A user loads a tape cartridge previously recorded at 2.6 GB density. The user then presses the Density Select button to select 10.0 GB density. The following events take place:
The amber 2.6 LED remains lit – the density has not yet changed and the
steadily lit LED reflects the tape’s recorded density.
The amber 10.0 LED blinks – this signals that a density change is pending.
The amber Density Override LED lights.
When a WRITE from BOT occurs:
The amber 2.6 LED turns off
The amber 10.0/15.0 LED lights steadily
The amber Density Override LED remains lit
Table 2-8 explains the activity of LED’s during density selection.
Quantum DLT 4000 Tape Drive 2-23
Hardware Implementation
Table 2–8 LED Activity During Density Selection
If… Then…
The density Select Button is not used
The density Select Button is used and the actual tape density is the same as the density selected via the button
The density Select Button is used and the actual tape density differs from the density selected via the button
The lighted LED’s show the actual density when the tape is being read from and written to. The LED’s light steadily; Density Override LED remains off.
The LED’s that reflect the actual density and the Density Override both are lit. For example, if the actual density is
10.0 GB and 10.0 GB is selected via the Select Button, the LED next to “10.0” lights.
The LED that reflects the actual density lights steadily. The LED that reflects the SELECTED density blinks. The Density Override lights steadily.
For example, if the actual tape density is 10.0 GB and the selected density is 6.0 GB, the 10.0 LED lights steadily, the
6.0 LED blinks, and the Density Override LED lights steadily.
2.6 POWER ON SELF TEST (POST)
When power is applied to the tape drive, the drive performs a POST. POST completes in about 15 seconds and the tape drive should respond normally to all commands; POST is complete after Stage 2 in Table 2-9. However, it might take longer for the media to become ready.
After a bus reset, the tape drive responds within a bus selection time-out period (per the ANSI SCSI specification).
The following table lists the sequence of events:
2-24 Quantum DLT 4000 Tape Drive
Hardware Implementation
Table 2–9 POST/Media Ready Activity
Stage Activity
1 The LED’s along the right-hand side of the front panel light in sequence from
top to bottom. All LED’s remain lit for a few seconds.
2 The LED’s along the left-hand side of the front panel light together for about
three seconds, then turn off. POST is complete after this stage.
3 The green Operate Handle, orange Write Protected, and amber User Cleaning
Tape LED’s turn off. The amber Tape in Use LED blinks while the tape drive initializes.
4 Following initialization, the tape drive is in one of the states described in Table
2-10. Upon completion, the POST is successful. If the POST is not successful, refer to Section 2.8 Troubleshooting.
Table 2–10 Tape Drive States Following Initialization
State LED Display and Activity
A tape cartridge is present and the handle is down.
No tape cartridge present. The Tape in Use LED = Off. The Operate Handle LED = On.
A tape cartridge is present, but the handle is up (not recommended).
The tape drive detects an error condition.
The drive is powered on with the handle in open position.
The tape drive loads the medium from the cartridge. The Tape In Use LED stops blinking and remains on. The LED next to the tape’s actual density is on. When the Density Override LED blinks, a density may be selected. The tape drive is ready for use and the media is positioned at BOT.
Insert/Release Handle is unlatched. Tape drive beeper sounds tone to signal that the handle may be raised and a tape cartridge inserted.
The Tape In Use LED = Off. The Operate Handle LED flashes. When the Insert/Release Handle is lowered, the cartridge loads. If handle will not lower, ensure the tape cartridge is pushed all the way into the tape drive.
Right- or left-hand LED’s blink repeatedly. Try to unload the tape and reinitialize the tape drive by pressing the Unload button or turn the drive power off then back on. The LED’s stop blinking and the drive attempts to reinitialize. Note that after pressing the Unload button you may have to wait five minutes before the Operate Handle LED lights due to the retry. The LED’s light steadily, then turn off if the test succeeds.
Operate Handle LED is blinking. Close the Insert/Release Handle and wait for LED to light steadily.
Quantum DLT 4000 Tape Drive 2-25
Hardware Implementation
2.7 TROUBLESHOOTING
Table 2-11 lists troubleshooting tips in the event that your tape drive fails its power-on self test or if it signals a problem via its front panel LED’s.
If, after attempting the recommended actions listed in Table 2-11, the problem still exists or recurs, a hardware failure may be the cause. Contact your service representative.
Table 2–11 Troubleshooting Chart
If… Then… You Should…
System does not recognize the tape drive.
System may not be configured to recognize the SCSI ID.
SCSI ID may not be unique Change the SCSI ID and reconfigure the
Configure system to recognize the tape drive’s ID.
system. The new ID becomes effective at the next power on.
SCSI adapter parameters may not be correct
SCSI signal cable may be loose Ensure SCSI cable is fully seated at each
SCSI terminator may be loose or not present on the bus
SCSI bus may not be terminated correctly
SCSI terminator may not be at end of bus or more than two terminators may be present.
SCSI bus may be too long.
Too many devices on the bus.
Check SCSI adapter documentation.
connector end.
Ensure correct, secure termination of bus.
If tape drive is last or only device on bus (except for adapter), make sure terminator is installed on tape drive.
If tape drive is not the last or only device on the bus, check the cable connections and ensure that the bus is properly terminated at each end.
Ensure that a terminator is installed at each end of the bus. One terminator is usually installed at the host end of the bus.
Limit bus length to ANSI SCSI standard for the SCSI interface being used.
Limit the number of devices on the bus (including the SCSI adapter) to match the limits of the interface being used.
2-26 Quantum DLT 4000 Tape Drive
Hardware Implementation
Table 2–11 Troubleshooting Chart (Continued)
If… Then… You Should…
System does not recognize the tape drive (cont.)
The tape drive does not power up.
All LED’s on the right or on the left side of the tape drive front panel are blinking.
When loading a tape cartridge, the LED’s on the right side of the tape drive front panel are blinking.
A device may not have been turned on and a valid SCSI ID may not have been configured prior to the system powering on and loading BIOS.
No power is reaching the tape drive.
A drive fault has occurred. If a tape was loaded, try to unload the
The tape drive has detected a possible drive leader problem.
Turn drives power on first, and then turn on power to the system. Do this so that the drive is properly recognized by the system.
Check the tape drive’s power cable connection at the rear of the drive.
tape and reinitialize the drive by pressing the Unload button, or by turning power to the drive off then back on. The LED’s stop blinking as the drive attempts to reinitialize. The LED’s light steadily again, then extinguish if the test succeeds. Be sure to isolate the tape that was loaded in the drive and perform the Tape Cartridge Inspection Procedure described in appendix D.2.
Isolate the tape cartridge from all other tape devices; not doing so may damage another tape device. Perform the Tape Cartridge Inspection Procedure described in appendix D.2 on the tape cartridge. Contact your service representative.
Nonfatal or fatal errors occur for which the cause cannot be determined.
SCSI bus termination or the SCSI bus cable connections may be incorrect.
The ac power source grounding may be incorrect (tabletop version).
Quantum DLT 4000 Tape Drive 2-27
Ensure the SCSI bus is terminated and that all connections are secure.
Use an ac outlet for the tabletop tape unit on the same ac line used by the host system.
Hardware Implementation
2-28 Quantum DLT 4000 Tape Drive
Chapter 3
SCSI DESCRIPTION
This chapter provides a detailed description of the logical interfaces of the tape drive. The drive is fully compliant with the ANSI SCSI-2 standard for tape drive devices and implements many optional features.
3.1 SCSI OVERVIEW
The Small Computer System Interface (SCSI) is a specification for a peripheral bus and command set that is an ANSI standard. The standard defines an I/O bus that supports up to eight devices (narrow SCSI).
ANSI defines three primary objectives of SCSI-2:
1. To provide host computers with device-independence within a class of
devices
2. To be backward-compatible with SCSI-1 devices that support bus parity
and that meet conformance level 2 of SCSI-1
3. To move device-dependent intelligence to the SCSI-2 devices
Important features of SCSI-2 implementation include the following:
Efficient peer-to-peer I/O bus with up to 16 devices
Asynchronous transfer rates that depend only on device implementation
and cable length
Logical addressing for all data blocks (rather than physical addressing)
Multiple initiators and multiple targets
Distributed arbitration (bus contention logic)
Command set enhancement
3.2 SCSI COMMANDS
ANSI classifies SCSI commands as mandatory, optional, or vendor-specific. The mandatory and optional commands implemented for the drives are summarized in Table 3–1 and described fully in Chapter 5, SCSI Commands.
Quantum DLT 4000 Tape Drive 3-1
SCSI Description
Table 3–1 Implemented ANSI SCSI-2 Commands
Command Code Class Description
Erase 19h Mandatory Causes all of the tape medium to be
erased, beginning at the current position on the logical unit.
INQUIRY 12h Mandatory Requests that drive information be sent
to the initiator. The initiator may also request additional information about the drive.
LOAD UNLOAD 1Bh Optional Requests that the target enable or
disable the logical unit for further operations. Prior to performing the load unload, the target ensures that all data, filemarks, and/or setmarks shall have transferred to the tape medium.
LOCATE 2Bh Optional Causes the target to position the logical
unit to the specified block address in a specified partition. When complete, the logical position is before the specified position. Prior to performing the load unload, the target ensures that all data, filemarks, and/or setmarks shall have transferred to the tape medium.
LOG SELECT 4Ch Optional Provides a means for the initiator to
manage statistical information maintained by the drive about the drive. This standard defines the format of the log pages but does not define the exact conditions and events that are logged.
LOG SENSE 4Dh Optional Provides a means for the initiator to
retrieve statistical information maintained by the drive about the drive.
3-2 Quantum DLT 4000 Tape Drive
SCSI Description
Table 3–1 Implemented ANSI SCSI-2 Commands (continued)
Command Code Class Description
MODE SELECT (6) 15h Optional Provides a means for the initiator to
specify device parameters.
MODE SENSE (6) 1Ah Optional Provides a means for a drive to report
parameters to the initiator.
PREVENT ALLOW
MEDIUM REMOVAL
READ 08h Mandatory Requests the drive to transfer data to the
READ BLOCK LIMITS 05h Mandatory Requests that the logical unit’s block
READ BUFFER 3Ch Optional Used in conjunction with the WRITE
READ POSITION 34 h Optional Reports the current position of the
RECEIVE DIAG RESULTS
RELEASE UNIT 17h Mandatory Used to release a previously reserved
1Eh Optional Requests that the target enable or
disable the removal of the medium in the logical unit. Medium cannot be removed if any initiator has medium removal prevented.
initiator.
length limits capability be returned
BUFFER command as a diagnostic function for testing target memory and the integrity of the SCSI bus. This command does not alter the medium.
logical unit and any data blocks in the buffer.
1Ch Optional Requests analysis data to be sent to the
initiator after completion of a SEND DIAGNOSTIC Command.
logical unit.
REQUEST SENSE 03h Mandatory Requests the drive to transfer sense data
to the initiator.
RESERVE UNIT 16h Mandatory Used to reserve a logical unit.
SEND DIAGNOSTIC 1Dh Mandatory Requests the drive to perform diagnostic
operations on itself.
Quantum DLT 4000 Tape Drive 3-3
SCSI Description
Table 3–1 Implemented ANSI SCSI-2 Commands (continued)
Command Code Class Description
SPACE 11h Mandatory Provides a selection of positioning
functions (both forward and backward) that are determined by the code and count.
TEST UNIT READY 00h Mandatory Provides a means to check if the logical
unit is ready.
VERIFY 2Fh Optional Requests the drive to verify the data
written to the medium.
WRITE 0Ah Optional Requests the drive to write the data
transferred from the initiator to the medium.
WRITE BUFFER 3Bh Optional Used in conjunction with the READ
BUFFER command as a diagnostic for testing target memory and the integrity of the SCSI bus.
Used to update drive firmware from the host via the SCSI bus.
WRITE FILEMARKS 10h Mandatory Requests that the target write the
specified number of filemarks or setmarks to the current position on the logical unit.
3.3 SIGNAL STATES
The following paragraphs describe signal values and SCSI ID bits.
3.3.1 Signal Values
All signal values are actively driven true (low voltage). Because the signal drivers are OR-tied, the bus terminator’s bias circuitry pulls false when it is released by the drivers at every SCSI device. If any device asserts a signal, (e.g., OR-tied signals), the signal is true. Table 3–2 shows the ANSI-specified and defined signal sources. Any device can assert RST at any time.
3-4 Quantum DLT 4000 Tape Drive
Table 3–2 Signal Sources
Signals
SCSI Description
Bus Phase BSY SEL C/D I/O
MSG REQ
BUS FREE None None None None None None
ARBITRATION All Winner None None S ID S ID
SELECTION I&T Init None Init Init Init
RESELECTION I&T Targ Targ Init Targ Targ
COMMAND Targ None Targ Init Init None
DATA IN Targ None Targ Init Targ Targ
DATA OUT Targ None Targ Init Init Init
STATUS Targ None Targ Init Targ None
MESSAGE IN Targ None Targ Init Targ None
MESSAGE OUT Targ None Targ Init Init None
All: The signal is driven by all SCSI devices that are actively arbitrating.
SCSI ID: Each SCSI device that is actively arbitrating asserts its unique SCSI ID bit. The other
seven (or fifteen) data bits are released. The parity bit DB (P or P1) can be released or driven true, but is never driven false during this phase.
I&T: The signal is driven by the initiator, drive, or both, as specified in the SELECTION and
RESELECTION phase.
ACK ATN DB(7–0)
DB(P)
DB(15-8) DB(P1)
Init: If driven, this signal is driven only by the active initiator.
None: The signal is released; that is, not driven by any SCSI device. The bias circuitry of the bus
terminators pulls the signal to the false state.
Winner: The signal is driven by the winning SCSI device.
Targ: If the signal is driven, it is driven only by the active drive.
Quantum DLT 4000 Tape Drive 3-5
SCSI Description
3.3.2 SCSI ID Bits
SCSI permits a maximum of eight SCSI devices on a SCSI bus (16 devices are permitted when using wide SCSI). Each SCSI device has a unique SCSI ID assigned to it. This SCSI ID provides an address for identifying the device on the bus. On the drive, the SCSI ID is assigned by configuring jumpers or connecting remote switches to the option connector. Chapter 2, Hardware Implementation has full instructions for setting the SCSI ID.
3.4 SCSI SIGNALS
The following paragraphs define SCSI signals and bus timing values.
3.4.1 SCSI Signal Definitions
Table 3–3 defines the SCSI bus signals.
Table 3–3 SCSI-2 Bus Signal Definitions
Signal Definition
ACK (acknowledge)
ATN (attention) A signal driven by an initiator to indicate that it has a message to send.
BSY (busy) An OR-tied signal that indicates that the bus is in use.
C/D (control/data)
DB(7–0,P) (data bus)
A signal driven by the initiator as an acknowledgment of receipt of data from a target or as a signal to a target indicating when the target should read the data (out) lines.
A signal driven by a target that indicates whether CONTROL or DATA information is on the DATA BUS. True (low voltage) indicates CONTROL.
Eight data-bit signals, plus a parity-bit signal that form a DATA BUS. DB(7) is the most significant bit and has the highest priority (8 or 16­bit) during ARBITRATION. Bit number, significance, and priority decrease downward to DB(0). A data bit is defined as 1 when the signal value is true (low voltage) and 0 when the signal value is false (high voltage). Data parity DB(P) is odd. Parity is undefined during ARBITRATION.
3-6 Quantum DLT 4000 Tape Drive
Table 3–3 SCSI-2 Bus Signal Definitions (continued)
Signal Definition
SCSI Description
DB(15–8,P1) (data bus)
I/O (input/output)
MSG (message) A signal driven by a target during the MESSAGE phase.
REQ (request) A signal driven by a target to indicate a request for an information
RST (reset)
SEL (select)
Eight data-bit signals, plus one parity-bit signal, that forms an extension to the DATA BUS. They are used for 16-bit (wide) interfaces. DB(15) is the most significant bit and has the higher priority (but below bit DB(0) during ARBITRATION. Bit number, significance, and priority decrease downward to DB(8). Data Parity DB (P1) is odd.
A signal driven by a target that controls the direction of data movement on the DATA BUS with respect to an initiator. True indicates input to the initiator.
Also used to distinguish between SELECTION and RESELECTION modes.
transfer to or from the initiator. Each byte of data transferred is accompanied with a REQ/ACK “handshake”. See also, ACK.
An OR-tied signal that initiates a RESET condition. An OR-tied signal used by an initiator to select a target or by a target to
reselect an initiator.
3.4.2 Signal Bus Timing
The ANSI SCSI-2 standard defines the SCSI bus timing values shown in Table 3–4.
Quantum DLT 4000 Tape Drive 3-7
SCSI Description
Timing Description Value Description
Arbitration Delay 2.4 µs Minimum time a SCSI device waits from asserting BSY
Assertion Period 90 ns Minimum time a drive asserts REQ while using
Bus Clear Delay 800 ns Maximum time for a SCSI device to stop driving all
Table 3–4 SCSI Bus Timing Values
for arbitration until the DATA BUS can be examined to see if arbitration has been won; there is no maximum time.
synchronous data transfers; also, the minimum time that an initiator asserts ACK while using synchronous data transfers.
bus signals after:
1. BUS FREE is detected.
2. SEL is received from another SCSI device during ARBITRATION.
3. Transition of RST to true.
For condition 1, the maximum time for a SCSI device
to clear the bus is 1200 ns (1.2 µs) from BSY and SEL
first becoming both false.
If a SCSI device requires more than a bus settle delay to detect BUS FREE, it clears the bus within a bus clear delay minus the excess time.
Bus Free Delay 800 ns Maximum time a SCSI device waits from its detection
of BUS FREE until its assertion of BSY when going to ARBITRATION.
Bus Set Delay 1.8 µs Maximum time for a device to assert BSY and its SCSI
ID bit on the DATA BUS after it detects BUS FREE to enter ARBITRATION.
Bus Settle Delay 400 ns Minimum time to wait for the bus to settle after
changing certain control signals as called out in the protocol definitions.
Cable Skew Delay 10 ns Maximum difference in propagation time allowed
between any two SCSI bus signals measured between any two SCSI devices.
1
Recommended Time.
3-8 Quantum DLT 4000 Tape Drive
SCSI Description
Table 3–4 SCSI Bus Timing Values (continued)
Timing Description Value Description
Data Release Delay 400 ns Maximum time for an initiator to release the DATA
BUS signals following the transition of the I/O signal from false to true.
Deskew Delay 45 ns Minimum time required to wait for all signals
(especially data signals) to stabilize at their correct, final value after changing.
Disconnection Delay 200 µs Minimum time that a drive waits after releasing BSY
before participating in an ARBITRATION when honoring a DISCONNECT message from the initiator.
Hold Time 45 ns Minimum time added between the assertion of REQ
or ACK and changing the data lines to provide hold time in the initiator or drive while using standard (slow) synchronous data transfers.
Negation Period 90 ns Minimum time that a drive negates REQ while using
synchronous data transfers; also, the minimum time
Power-On to Selection
10 s
than an initiator negates ACK while using synchronous data transfers.
1
Recommended maximum time from power application until a drive is able to respond with appropriate status and sense data to the TEST UNIT READY, INQUIRY, and REQUEST SENSE commands.
1
Reset to Selection Time
250 ms
Recommended maximum time after a hard RESET
1
condition until a drive is able to respond with appropriate status and sense data to the TEST UNIT READY, INQUIRY, and REQUEST SENSE commands.
Reset Hold Time 25 µs Minimum time for which RST is asserted; there is no
maximum time.
Selection Abort Time 200 µs Maximum time that a drive (or initiator) takes from its
most recent detection of being selected (or reselected) until asserting a BSY response.
1
Recommended Time.
Quantum DLT 4000 Tape Drive 3-9
SCSI Description
Timing Description Value Description
Table 3–4 SCSI Bus Timing Values (continued)
Selection Time-Out Delay
Transfer Period (set during an SDTR message.)
1
Recommended Time.
3.5 SCSI BUS PHASES
The SCSI architecture includes eight distinct phases:
1. BUS FREE phase
2. ARBITRATION phase
3. SELECTION phase
4. RESELECTION phase
5. COMMAND phase
6. DATA phases (In/Out)
250 ms
Recommended minimum time a SCSI device should
1
wait for a BSY response during SELECTION or RESELECTION before starting the time-out procedure.
Minimum time allowed between the leading edges of successive REQ pulses and of successive ACK pulses while using standard or fast synchronous data transfers. The period range is 200 to 500ns minimum, standard, or 100 to 500ns minimum, fast­synchronous.
7. STATUS phase
8. MESSAGE phases (In/Out)
The last four phases are called the “information transfer phases”.
The SCSI bus can never be in more than one phase at any given time. In the following descriptions, signals that are not mentioned are not asserted.
3.5.1 BUS FREE Phase
The BUS FREE phase indicates that there is no current I/O process and that the SCSI bus is available for a connection.
SCSI devices detect the BUS FREE phase after the SEL and BSY signals are both false for at least one bus settle delay.
3-10 Quantum DLT 4000 Tape Drive
SCSI Description
During normal operation, the BUS FREE phase is entered when the drive releases the BSY signal. However, the BUS FREE phase can be entered following the release of the SEL signal after a SELECTION or RESELECTION phase time­out. BUS FREE might be entered unexpectedly. If, for example, an internal hardware or firmware fault makes it unsafe for the tape drive to continue operation without a full reset (similar to a power-up reset), or if ATN is asserted or a bus parity error is detected during non-tape data transfers.
CAUTION
Any occurrence of a bus parity error (i.e., a single-bit error) should be considered serious: it implies the possibility of undetected double-bit error may exist on the bus. This may cause undetected data corruption. On properly configured SCSI buses, parity errors are extremely rare. If any are detected they should be addressed by improving the configuration of the SCSI bus. A well-configured SCSI bus in a normal environment should be virtually free of bus parity errors.
Bus parity errors cause the tape drive to retry the operation, go to the STATUS phase, or go to BUS FREE and prepare Sense Data. Retrying of parity errors during Data Out Phase when writing is normally not done, but can be enabled by changing the EnaParErrRetry parameter in the VU EEROM Mode Page. This feature is not enabled by default because of possible negative impact on device performance (the data stream on writes cannot be pipelined as well).
Initiators normally do not expect the BUS FREE phase to begin because of the drive’s release of the BSY signal unless it has occurred after the detection of a reset condition or after a drive has successfully transmitted or received one of the following messages:
Messages Transmitted from Drive:
DISCONNECT
COMMAND COMPLETE
Quantum DLT 4000 Tape Drive 3-11
SCSI Description
Messages Received by Drive:
ABORT
BUS DEVICE RESET
RELEASE RECOVERY
If an initiator detects the release of the BSY signal by the drive at any other time, the drive is indicating an error condition to the initiator. The drive can perform this transition to the BUS FREE phase independently of the state of the ATN signal. The initiator manages this condition as an unsuccessful I/O process termination. The drive terminates the I/O process by clearing all pending data and status information for the affected nexus. The drive can optionally prepare sense data that can be retrieved by a REQUEST SENSE command.
Bus Free Sequence
1. BSY and SEL signals are continuously false for one bus settle delay.
2. SCSI devices release all SCSI bus signals within one bus clear delay.
If a SCSI device requires more than one bus settle delay to detect the BUS FREE phase, then it releases all SCSI bus signals within one bus clear delay minus the excess time to detect the BUS FREE phase.
The total time to clear the SCSI bus cannot exceed one bus settle delay plus one bus clear delay.
3.5.2 ARBITRATION Phase
The ARBITRATION phase allows one SCSI device to gain control of the SCSI bus so that it can initiate or resume an I/O process.
The SCSI device arbitrates for the SCSI bus by asserting both the BSY signal and its own SCSI ID after a BUS FREE phase occurs.
Arbitration Sequence
1. The SCSI device waits for the BUS FREE phase to occur.
2. The SCSI device waits a minimum of one bus free delay after detection of the
BUS FREE phase before driving any signal.
3. The SCSI device arbitrates for the SCSI bus by asserting the BSY signal and
its SCSI ID.
3-12 Quantum DLT 4000 Tape Drive
SCSI Description
4. The SCSI device waits at least an arbitration delay to determine arbitration
results.
NOTE
Step 4 requires that every device complete the arbitration phase to the point of SEL being asserted (for a SELECTION or RESELECTION phase) to avoid hanging the bus.
If a higher priority SCSI ID bit is true on the DATA BUS, the SCSI
device loses the arbitration.
The losing SCSI device releases the BSY signal and its SCSI ID bit
within one bus clear delay after the SEL signal asserted by the arbitration winner becomes true.
The losing SCSI device waits for the SEL signal to become true
before releasing the BSY signal and SCSI ID bit when arbitration is lost.
The losing SCSI device returns to Step 1.
If no higher priority SCSI ID bit is true on the DATA BUS, the SCSI
device wins the arbitration and asserts the SEL signal.
The winning SCSI device waits at least one bus clear delay plus one
bus settle delay after asserting the SEL signal before changing any signals.
3.5.3 SELECTION Phase
The SELECTION phase allows an initiator to select a drive to initiate a drive function.
The SCSI device that won the arbitration has both the BSY and SEL signals asserted and has delayed at least one bus clear delay plus one bus settle delay before ending the ARBITRATION phase. The SCSI device that won the arbitration becomes an initiator by not asserting the I/O signal.
During SELECTION, the I/O signal is negated so that this phase can be distinguished from the RESELECTION phase.
Quantum DLT 4000 Tape Drive 3-13
SCSI Description
3.5.3.1 Selection Sequence
The initiator:
1. Sets the DATA BUS to the OR of its SCSI ID bit and the drive’s SCSI ID
bit.
2. Asserts the ATN signal (signaling that a MESSAGE OUT phase is to follow
the SELECTION phase).
3. Waits at least two deskew delays.
4. Releases the BSY signal.
5. Waits at least one bus settle delay.
6. Looks for a response from the drive.
The drive:
7. Determines that it is selected when the SEL signal and its SCSI ID bit are
true and the BSY and I/O signals are false for at least one bus settle delay.
8. Can examine the DATA BUS to determine the SCSI ID of the selecting
initiator.
9. Asserts the BSY signal within a selection abort time of its most recent
detection of being selected (this is required for correct operation of the selection time-out procedure).
The drive does not respond to a selection if bad parity is detected. Also, if more than two SCSI ID bits are on the DATA BUS, the drive does not respond to selection.
Note that the initiator will release the SEL signal and may change the DATA BUS no less than two deskew delays after it detects that the BSY signal is true. The drive waits until the SEL signal is false before asserting the REQ signal to enter an information transfer phase. Other signals (e.g., MSG, C/D) may also be asserted.
3.5.3.2 Selection Time-Out
Two optional time-out procedures are specified for clearing the SCSI bus if the initiator waits a minimum of a selection time-out delay and there has been no BSY signal response from the drive.
3-14 Quantum DLT 4000 Tape Drive
The initiator asserts the RST signal.
1. The initiator follows these steps: a) Continues asserting the SEL and ATN signals and releases the DATA
BUS.
b) If it has not detected the BSY signal to be true after at least a selection
abort time plus two deskew delays, the drive releases the SEL and ATN signals, allowing the SCSI bus to go to the BUS FREE phase.
When responding to selection, SCSI devices ensure that the selection was still valid within a selection abort time of their assertion of the BSY signal. Failure to comply with the requirement could result in an improper selection.
3.5.4 RESELECTION Phase
RESELECTION is an optional phase that allows a drive to reconnect to an initiator to continue an operation that was previously started by the initiator but was suspended by the drive.
The initiator determines that it is reselected when the SEL and I/O signals and its SCSI ID bit are true, and the BSY signal is false for at least one bus settle delay.
SCSI Description
3.5.4.1 Reselection Sequence
The drive:
1. Upon completing the ARBITRATION phase, asserts both the BSY and SEL
signals.
2. Delays at least one bus clear delay plus one bus settle delay.
3. Asserts the I/O signal.
4. Sets the DATA BUS to the logical OR of its SCSI ID bit and the initiator’s
SCSI ID bit.
5. Waits at least two deskew delays.
6. Releases the BSY signal.
7. Waits at least one bus settle delay before looking for a response from the
initiator.
Quantum DLT 4000 Tape Drive 3-15
SCSI Description
The initiator:
8. Determines that it is selected when the following occur for at least one bus
settle delay: SEL, I/O, and the initiator’s SCSI ID bit are true and BSY is false.
9. Examines the DATA BUS to determine the SCSI ID of the reselecting drive.
10. Asserts the BSY signal within a selection abort time of its most recent
detection of being reselected.
The initiator does not respond to a RESELECTION phase if bad parity is detected or if more than two SCSI ID bits are on the DATA BUS.
The drive:
11. Detects the BSY signal is true.
12. Asserts the BSY signal.
13. Waits at least two deskew delays.
14. Releases the SEL signal.
15. The drive can then change the I/O signal and the DATA BUS.
The initiator:
16. Detects the SEL signal is false.
17. Releases the BSY signal.
The drive:
18. Continues asserting the BSY signal until it relinquishes the SCSI bus.
3.5.4.2 Reselection Time-Out
Two optional time-out procedures are specified for clearing the SCSI bus if the initiator waits a minimum of a selection time-out delay and there has been no BSY signal response from the drive.
1. The initiator asserts the RST signal.
2. The initiator follows these steps: a) Continues asserting the SEL and ATN signals and releases the DATA
BUS.
b) If it has not detected the BSY signal to be true after at least a selection
abort time plus two deskew delays, releases the SEL and ATN signals, allowing the SCSI bus to go to the BUS FREE phase.
3-16 Quantum DLT 4000 Tape Drive
SCSI devices that respond to the RESELECTION phase must ensure that the reselection is still valid within a selection abort time of asserting the BSY signal.
3.5.5 Information Transfer Phases
1. The tape drive supports narrow asynchronous and synchronous data transfers.
2. Both differential and single-ended versions of the tape drive are available.
3. Odd parity is generated during all information transfer phases during which the
device writes data to the SCSI bus, and parity is checked during all transfer phases in which data is read from the bus by the tape drive. Parity checking can be disabled (Chapter 2).
4. The ANSI SCSI specification refers to mini-libraries as “medium changers.” In this
chapter the term “mini-libraries” is used to describe these devices.
5. The DLT 4000 supports block size of 1byte to 16 Mbytes.
6. Disconnects from the SCSI bus are done at regular intervals during information
transfer phases to allow other devices to access the bus. These disconnects are user-configurable via the Disconnect-Reconnect Page of the SCSI MODE SELECT command.
SCSI Description
NOTES
7. The tape drive does not act as an initiator on the SCSI bus. Therefore, the drive
does not 1) generate unsolicited interrupts to the bus, 2) initiate its own SCSI commands, and 3) assert bus reset.
8. A mini-library subsystem is assigned two logical unit numbers (LUNs): the tape
drive is always LUN 0, and the mini-library component has a default LUN of 1, but may be reconfigured to any LUN from 0 to 15 via the SCSI MODE SELECT command.
Quantum DLT 4000 Tape Drive 3-17
SCSI Description
The COMMAND, DATA, STATUS, and MESSAGE phases are known as the Information Transfer Phases because they are used to transfer data or control information.
The C/D, I/O, and MSG signals are used to distinguish between the different
information transfer phases (Table 3−5). The drive asserts these three signals
and so controls all information transfer phase changes. The drive can also cause a BUS FREE phase by releasing the MSG, C/D, I/O, and BSY signals. The initiator can request a MESSAGE OUT phase by asserting the ATN signal.
The information transfer phases use one or more REQ/ACK handshakes to control the information transfer. Each REQ/ACK handshake allows the transfer of one byte of information. During the information transfer phases, the BSY signal remains true and the SEL signal remains false. Additionally, the drive continuously envelopes the REQ/ACK handshake(s) with the C/D, I/O, and MSG signals in such a manner that these control signals are valid for one bus settle delay before the assertion of the REQ signal of the first handshake and remain valid after the negation of the ACK signal at the end of the handshake of the last transfer of the phase.
After the negation of the ACK signal of the last transfer of the phase, the drive can prepare for a new phase by asserting or negating the C/D, I/O, and MSG signals. These signals can be changed together or individually. They can be changed in any order and can be changed more than once (although each line should change only once). A new phase does not begin until the REQ signal is asserted for the first byte of the new phase.
A phase ends when the C/D, I/O, or MSG signal changes after the negation of the ACK signal. The time between the end of a phase and the assertion of the REQ signal beginning a new phase is undefined. An initiator is allowed to anticipate a new phase based on the previous phase, the expected new phase, and early information provided by changes in the C/D, I/O, and MSG signals. However, the anticipated phase is not valid until the REQ signal is asserted at the beginning of the next phase.
Information Transfer Direction
True I/O Signal: from drive to initiator
False I/O Signal: from initiator to drive
3-18 Quantum DLT 4000 Tape Drive
Signal
SCSI Description
Table 3–5 Information Transfer Phases
MSG
0 0 0 DATA OUT Initiator to drive.
0 0 1 DATA IN Drive to initiator.
0 1 0 COMMAND Initiator to drive.
0 1 1 STATUS Drive to initiator.
1 1 0 MESSAGE OUT Initiator to drive.
C/D I/O Phase Name Direction of Transfer/ Definition
Allows the drive to request that data be sent from the initiator to the drive.
Allows the drive to send data to the initiator.
Allows the drive to request a command from the initiator.
Allows the drive to send status information be sent from the drive to the initiator.
Allows the drive to request that message(s) be sent from the initiator to the drive; the drive invokes this phase in response to the attention condition created by the initiator.
The drive handshakes byte(s) until the ATN signal is negated, except when rejecting a message.
See 3.5.5.4 Message Out — Additional
Conditions.
1 1 1 MESSAGE IN Drive to initiator.
Allows the drive to send message(s) to the initiator.
Quantum DLT 4000 Tape Drive 3-19
SCSI Description
3.5.5.1 Asynchronous Data Transfer
Drive to Initiator Transfer Procedure
1. The drive drives the DB (7–0, P) signals to their desired values.
2. Drive delays at least one deskew delay plus a cable skew delay.
3. Drive asserts the REQ signal.
4. Initiator reads the DB (7–0, P) signals.
5. Initiator indicates its acceptance of the data by asserting the ACK signal.
6. When ACK is true at the drive, drive can change or release the DB (7–0, P)
signals.
7. Drive negates the REQ signal.
8. Initiator negates the ACK signal.
9. Drive can continue the transfer by driving the DB (7–0, P) signals and
asserting the REQ signal (Steps 1 – 3).
Initiator-to-Drive Transfer Procedure
1. Drive asserts the REQ signal.
2. Initiator drives the DB (7–0, P) signals to their desired values.
3. Initiator delays at least one deskew delay plus a cable skew delay.
4. Initiator asserts the ACK signal.
5. When ACK is true at the drive, drive reads the DB (7–0, P) signals.
6. Drive negates the REQ signal.
7. Initiator can change or release the DB (7–0, P) signals.
8. Initiator negates the ACK signal.
9. Drive can continue the transfer by asserting the REQ signal (Step 1).
3.5.5.2 Synchronous Data Transfer
Synchronous Data Transfer is optional and is only used in DATA phases and only if a synchronous data transfer agreement is established. The REQ/ACK offset specifies the maximum number of REQ pulses that can be sent by the drive in advance of the number of ACK pulses received from the initiator, establishing a pacing mechanism. If the number of REQ pulses exceeds the number of ACK pulses by the REQ/ACK offset, the drive does not assert the
3-20 Quantum DLT 4000 Tape Drive
SCSI Description
REQ signal until after the leading edge of the next ACK pulse is received. For successful completion of the data phase, the number of ACK and REQ pulses must be equal.
The initiator sends one ACK signal pulse for each REQ pulse received. The ACK signal can be asserted as soon as the leading edge of the corresponding REQ pulse has been received.
Drive-to-Initiator Transfer Procedure
1. The drive sets the DB (7–0, P) signals to the desired values. The DB (7–0,
P) signals are held valid for a minimum of one deskew delay plus one cable skew delay after REQ is asserted.
2. Drive delays at least one deskew delay plus a cable skew delay.
3. Drive asserts the REQ signal for a minimum of one assertion period. Drive
can negate the REQ signal and change or release the DB (7-0, P) signals.
4. Initiator reads the DB (7-0, P) signals within one hold time of the
transition of the REQ signal to true.
5. Initiator indicates its acceptance of the data by asserting an ACK pulse.
6. The drive waits at least the greater or these periods before again asserting
REQ:
c) A transfer period from the last transition of the REQ signal to true, or d) A negation period from the last transition of the REQ signal to false.
7. The initiator waits at least the greater of these periods before reasserting
ACK:
a) A transfer period from the last transition of the ACK signal to true, or b) A negation period from the last transition of the ACK signal to false.
Initiator-to-Drive Transfer Procedure
Initiator transfers one byte for each REQ pulse received.
1. Drive asserts the REQ signal.
2. After receiving the leading edge of the REQ signal, initiator drives the DB
(7–0, P) signals to their desired values. The DB (7-0, P) signals are held valid for at least one deskew delay plus one cable skew delay plus one hold time delay after the assertion of the ACK signal.
3. Initiator delays at least one deskew delay plus a cable skew delay.
4. Initiator asserts the ACK signal for a minimum of one assertion period.
5. Initiator can negate the ACK signal and change or release the DB (7-0, P)
signals.
Quantum DLT 4000 Tape Drive 3-21
SCSI Description
6. Drive reads the DB (7-0, P) signals within one hold time of the transition of
the ACK signal to true.
7. The drive waits at least the greater of these periods before again asserting
the REQ signal:
a) A transfer period from the last transition of the REQ signal to true, or b) A negation period from the last transition of the REQ signal to false.
8. The initiator waits at least the greater of the following periods before again
asserting the ACK signal:
a) A transfer period from the last transition of the ACK signal to true, or b) A negation period from the last transition of the ACK signal to false.
3.5.5.3 Signal Restrictions Between Phases
When the SCSI bus is between two information transfer phases, the following restrictions apply to the SCSI bus signals:
The BSY, SEL, REQ, and ACK signals do not change.
The C/D, I/O, MSG, and DATA BUS signals can change.
When changing the DATA BUS direction from out (initiator-driving) to in
(drive-driving), the drive delays driving the DATA BUS by at least a data release delay plus one bus settle delay after asserting the I/O signal. The initiator releases the DATA BUS no later than a data release delay after the transition of the I/O signal to true.
When switching the DATA BUS from in to out, the drive releases the DATA
BUS no later than a deskew delay after negating the I/O signal.
The ATN and RST signals can change as defined under the descriptions for
the attention condition (Section 3.6.1) and reset condition (Section 3.6.2).
3.5.5.4 STATUS Phase
The tape drive enters the status phase just once per command unless a retry is requested by the initiator. The only exception is during error cases when the device goes immediately to bus free, as defined in the ANSI SCSI-2 specification.
Status bytes the tape drive can return are listed in the following table:
3-22 Quantum DLT 4000 Tape Drive
SCSI Description
Table 3–6 Status Bytes
Status Bytes Returned from Tape Drive Definition
GOOD (00h) This status indicates that the drive successfully completed
the command.
CHECK CONDITION (02h) A contingent allegiance condition occurred. The REQUEST
SENSE command should be sent following this status to determine the nature of the event.
BUSY (08h) Target is busy. This status is returned whenever the device
is unable to accept a command from an otherwise acceptable initiator. The initiator should reissue the command at a later time.
INTERMEDIATE GOOD (10h) This status is returned instead of GOOD for commands
issued with the LINK bit set = 1. Following the return of this status, the drive proceeds to the COMMAND phase for the transfer of the next linked command.
RESERVATION CONFLICT (18h) This status is returned by the drive whenever a SCSI device
attempts to access the drive when it has been reserved for another initiator with a RESERVE UNIT command.
COMMAND TERMINATED (22h) This status is returned for a command that was terminated
via a TERMINATE I/O PROCESS message. This status also indicates that a contingent allegiance condition has occurred.
Quantum DLT 4000 Tape Drive 3-23
SCSI Description
In contrast to the BUSY status condition, the DRIVE NOT READY Sense Key is returned as part of the Sense data following a REQUEST SENSE command and indicates that a media access command has been issued but that the media is not ready to be accessed. For example, the tape cartridge is not installed, the tape medium has been unloaded, the tape drive is currently initializing the tape medium to prepare it for access, etc.
In the DRIVE NOT READY state, the initiator cannot perform any operation that would cause tape motion (READ, WRITE, VERIFY, for example). These commands return a CHECK CONDITION status with a DRIVE NOT READY sense key. The initiator may execute commands that do not require tape motion or access to the tape medium, and a GOOD status may be the result.
3.6 SCSI BUS CONDITIONS
The SCSI bus has two asynchronous conditions: Attention and Reset.
NOTES
3.6.1 Attention Condition
The attention condition informs a drive that an initiator has a message ready. The drive gets the message by performing a MESSAGE OUT phase. The attention condition requires the following timing:
The initiator creates the attention condition by asserting ATN at any time
except during the ARBITRATION or BUS FREE phases.
The initiator negates the ATN signal at least two deskew delays before
asserting the ACK signal while transferring the last byte of the message.
If the drive detects that the initiator failed to meet this requirement, then
the drive goes to BUS FREE.
Before transition to a new bus phase, the initiator asserts the ATN signal,
then waits at least two deskew delays before negating the ACK signal for the last byte transferred in the current bus phase. Asserting the ATN signal later cannot be honored until a later bus phase and then cannot result in the expected action.
The drive responds with MESSAGE OUT as described in the following table:
3-24 Quantum DLT 4000 Tape Drive
SCSI Description
Table 3–7 Drive MESSAGE OUT Phase Response
ATN Signal True in Phase... The Drive Enters MESSAGE OUT…
COMMAND After transferring part or all of the command descriptor block
bytes.
DATA At the drive’s earliest convenience (often on a logical block
boundary). The initiator continues REQ/ACK handshakes until it detects the phase change.
STATUS After the status byte has been acknowledged by the initiator.
MESSAGE IN Before it sends another message. This permits a MESSAGE
PARITY ERROR message from the initiator to be associated with the appropriate message.
SELECTION
1
RESELECTION
2
Immediately after that SELECTION phase.
After the drive has sent its IDENTIFY message for that RESELECTION phase.
1
Before the initiator releases BSY, provided the initiator asserted ATN.
2
The initiator should only assert the ATN signal during a RESELECTION phase to transmit a BUS
DEVICE RESET or DISCONNECT message.
The initiator keeps the ATN signal asserted if more than one byte is to be transferred. The initiator can negate the ATN signal at any time, except it does not negate the ATN signal while the ACK signal is asserted during a MESSAGE OUT phase. Normally, the initiator negates the ATN signal while the REQ signal is true and the ACK signal is false during the last REQ/ACK handshake of the MESSAGE OUT phase.
3.6.2 Reset Condition
The tape drive responds to power-on and/or bus reset conditions as described:
All tape drive SCSI lines assert high impedance when the tape drive is
powered off.
The drive does not generate any spurious signals on the SCSI bus when the
drive is powered on.
Within five (5) seconds of power-on, and within 250 milliseconds (typically
under 4 milliseconds) after a bus reset, the tape drive responds to SCSI bus selections and returns the appropriate normal responses. Tape motion
Quantum DLT 4000 Tape Drive 3-25
SCSI Description
commands are returned with Check Condition status, Sense Key of Not Ready, until the medium has been made ready.
The tape medium is rewound to Beginning of Partition (BOP, i.e.,
Beginning of Tape [BOT]).
Note that the tape drive does not implement the hard reset alternative for bus RESET processing.
The tape drive recognizes multiple bus resets in succession as well as bus resets of arbitrarily long duration (powering on conditions). It recovers within the time limits specified above following the last bus reset.
3.6.3 Queued Unit Attentions
Queued Unit Attentions are implemented on the tape drive and are maintained separately for each valid LUN for each initiator. Unit Attentions are created as a result of the following circumstances:
Power on
Bus reset
Bus device reset message
When the media may have changed asynchronously
When another initiator has changed the mode parameters
When a firmware (microcode) update has completed
Two (2) queued Unit Attentions are not unusual. For example, if a drive is powered up and a cartridge is loaded, “power up” and “not ready to ready transition” Unit Attention messages are created. Due to a limited number of Unit Attention buffers, if an initiator does not clear Unit Attentions queued for it, the tape drive at some point stops generating new Unit Attention messages for the Initiator-Logical Unit (I-L) combination (existing messages remain queued).
A LOAD command does not generate a Unit Attention message for the initiator that issued the command, since the transition to ready is synchronous.
3-26 Quantum DLT 4000 Tape Drive
Chapter 4
MESSAGES
The SCSI message system allows communication between an initiator and the drive for interface management and command qualification. Messages can be originated by either the initiator or the drive. This section contains a detailed description of the messages supported by the drives.
4.1 MESSAGE FORMAT
A message can be one or more bytes in length. One or more messages can be sent during a single MESSAGE phase, but a message cannot be split over MESSAGE phases. The initiator is required to end the MESSAGE OUT phase (by negating ATN) when it sends certain messages that are identified in Table 4–2.
When a connection to the drive is established (i.e., the drive is selected with ATN asserted), the first message byte passed by the initiator must be either an IDENTIFY, ABORT, or BUS DEVICE RESET message. If not, the drive discards the message, saves no status information, and goes to the BUS FREE phase.
If an initiator supplies an unsupported message (for example, COMMAND COMPLETE or a reserved or undefined message code), the drive returns a MESSAGE REJECT message and continues where it left off (possibly returning to MESSAGE OUT if ATN is raised).
The first byte of the message, as defined in Table 4–1, determines the format of the message.
Quantum DLT 4000 Tape Drive 4-1
Messages
Table 4–1 Message Format
Message Code Message
00h One-byte message (COMMAND COMPLETE)
01h Extended message
02h – 1Fh One-byte message
20h – 2Fh Two-byte message
40h – 7Fh Reserved
80h – FFh One-byte message (IDENTIFY)
The DLT 4000 tape drive supports the messages listed in Table 4–2. The message code and the direction of the message flow is also included in the table (In = target to initiator, Out = initiator to target).
4-2 Quantum DLT 4000 Tape Drive
Table 4–2 Supported Messages
Message Message Code Direction
ABORT 06h Out
BUS DEVICE RESET 0Ch Out
COMMAND COMPLETE 00h In
DISCONNECT 04h In Out
Messages
EXTENDED MESSAGE (Synchronous Data Transfer Request, or SDTR)
IDENTIFY 80h – FFh In Out
INITIATOR DETECTED ERROR 05h Out
LINKED COMMAND COMPLETE 0Ah In
LINKED COMMAND COMPLETE (with flag) 0Bh In
MESSAGE PARITY ERROR 09h Out
MESSAGE REJECT 07h In
NO OPERATION 08h Out
RESTORE POINTERS 03h In
SAVE DATA POINTER 02h In
*
Extended message (Figure 4–1); described in Section 4.2.14.
*
01h In Out
Two-byte messages consist of two consecutive bytes. The value of the first byte, as defined in Table 4–1, determines which message is to be transmitted. The second byte is a parameter byte that is used as defined in the message description.
A value of 1 in the first byte indicates the beginning of a multiple-byte extended message. The minimum number of bytes sent for an extended message is three. The extended message format is shown in Figure 4–1 and the data fields are described in Table 4–3.
Quantum DLT 4000 Tape Drive 4-3
Messages
Bit
Byte
0 Extended Message (01h)
1 Extended Message Length
2 Extended Message Code
3 to n-1 Extended Message Arguments
7 6 5 4 3 2 1 0
Figure 4–1 Extended Message - Data Format
Table 4–3 Extended Message - Field Description
Field Description
Extended Message Length
This field specifies the length, in bytes, of the Extended Message Code plus the Extended Message Arguments that follow. Therefore, the total length of the message is equal to the Extended Message Length plus 2.
A value of 0 for the Extended Message Length indicates that 256 bytes follow.
Extended Message Code The drive supports some Extended Messages. They are:
01h SYNCHRONOUS DATA TRANSFER REQUEST
80h – FFh Vendor Unique (for more information, refer to the section for the INQUIRY command in Chapter 5).
4-4 Quantum DLT 4000 Tape Drive
4.2 SUPPORTED SCSI MESSAGES
Following are descriptions of each of the messages supported by the drive.
4.2.1 ABORT Message (06h)
This message is sent from the initiator to the target to clear the current I/O process on the selected unit. Buffered (cached) write operations are completed if possible. The target goes directly to the BUS FREE phase after successful receipt of this message. Current settings of MODE SELECT parameters and reservations are not affected. Commands, data, and status for other initiators are not affected.
This message can be sent to a logical unit that is not currently performing an operation for the initiator. If no unit has been selected, the target goes to BUS FREE phase and no commands, data, or status on the target are affected.
4.2.2 BUS DEVICE RESET Message (0Ch)
The BUS DEVICE RESET message is sent from an initiator to direct the drive to clear all I/O processes on the drive. The message causes the drive to:
Messages
1. Flush the contents of cache to tape and go to the BUS FREE phase.
2. Execute a hard reset, leaving it as if a Bus Reset had occurred.
The drive creates a Unit Attention condition for all initiators after accepting and processing a Bus Device Reset message. The additional sense code is set to POWER ON, RESET, or BUS DEVICE RESET OCCURRED.
4.2.3 COMMAND COMPLETE Message (00h)
The COMMAND COMPLETE message is sent by the drive to an initiator to indicate that an I/O process has completed and that valid status has been sent to the initiator. After successfully sending this message, the drive goes to the BUS FREE phase by releasing the BSY signal. The drive considers the message transmission successful when it detects the negation of ACK for the COMMAND COMPLETE message with the ATN signal false. If a COMMAND COMPLETE message is received by the tape drive, it is handled as an illegal message: the drive returns MESSAGE REJECT and enters its STATUS phase, reporting CHECK CONDITION with the sense key set to COMMAND ABORTED.
Quantum DLT 4000 Tape Drive 4-5
Messages
4.2.4 DISCONNECT Message (04h)
The DISCONNECT message is sent from the drive to inform the initiator that the present connection is going to be broken (the drive plans to disconnect by releasing the BSY signal) and a later reconnect will be required to complete the current I/O process. The message does not cause the initiator to save the data pointer. After sending the message, the drive goes to the BUS FREE phase by releasing the BSY signal.
The DISCONNECT message can also be sent by the initiator to tell the drive to suspend the current phase and disconnect from the bus. The drive’s response to and its handling of a DISCONNECT message are based on when, in the I/O process, the initiator introduces the DISCONNECT message. Table 4–4 summarizes the drive’s response.
Table 4–4 Drive Response to DISCONNECT Message
BUS Phase Drive Response
SELECTION The drive discards the DISCONNECT message and goes to BUS FREE.
COMMAND The drive discards the DISCONNECT message and goes to BUS FREE. The
ATTENTION request is ignored while the Command Descriptor Block is fetched. The drive does not switch to MESSAGE OUT until the current DMA completes.
DATA The ATTENTION request is ignored while the current data transfer completes;
that is, the drive does not switch to MESSAGE OUT until after the current DMA completes. The drive returns a MESSAGE REJECT message and responds with CHECK CONDITION status, indicating the command aborted because of an invalid message.
STATUS The drive sends a MESSAGE REJECT message, then sends COMMAND
COMPLETE.
MESSAGE IN The drive sends a MESSAGE REJECT message and switches to the BUS FREE
phase.
4-6 Quantum DLT 4000 Tape Drive
4.2.5 IDENTIFY Message (80h - FFh)
The IDENTIFY message is sent by either the initiator or the drive to establish or re-establish the physical connection path between an initiator and target for a particular logical unit, under the conditions listed below. Figure 4–2 shows the format of the IDENTIFY message and Table 4–5 describes the data field contents.
Messages
Bit
Byte
7 6 5 4 3 2 1 0
Identify DiscPriv
LUNTAR
Reserved LUNTRAN
Figure 4–2 IDENTIFY Message - Data Format
Table 4–5 IDENTIFY Message - Field Description
Field Description
Identify The Identify bit must be set to 1. This identifies the message as an IDENTIFY
message.
DiscPriv Disconnect Privilege. The DiscPriv can be 0, provided that no other I/O process is
currently active in the drive. If not set to 1 and other I/O processes are currently active in the drive, the drive returns BUSY status.
LUNTAR The Logical Unit/Target Routine (LUNTAR) field must be set to zero. The drive
supports a single Logical Unit Number (LUN 0 ). A LUNTAR bit of one causes the drive to send a MESSAGE REJECT message and switch to the BUS FREE phase.
Reserved The Reserved bits must be zero. If a Reserved bit is non-zero, the drive returns a
MESSAGE REJECT message and switches to the BUS FREE phase.
LUNTRN Logical Unit Number.
Quantum DLT 4000 Tape Drive 4-7
Messages
4.2.6 INITIATOR DETECTED ERROR Message (05h)
The INITIATOR DETECTED ERROR message is sent from an initiator to inform the drive that an error has occurred that does not preclude the drive from retrying the operation (a bus parity error, for example). The source of the error may either be related to previous activities on the SCSI bus or may be only drive­related. When received, the tape drive attempts to re-transfer the last command, data, or status bytes by using the RESTORE POINTER message mechanism.
The drive’s response to and its handling of an INITIATOR DETECTED ERROR message are based on when, in the I/O process, the initiator introduces the message. Table 4–6 summarizes the drive’s response.
Table 4–6 Drive Response to INITIATOR DETECTED ERROR Message
BUS Phase Drive Response
SELECTION The drive discards the INITIATOR DETECTED ERROR message and then goes
to the BUS FREE phase.
COMMAND The drive discards any Command Descriptor Block bytes fetched from the
initiator, sets the Sense Key to ABORTED COMMAND, sets the Additional Sense Code to INITIATOR DETECTED ERROR MESSAGE RECEIVED. It sends the CHECK CONDITION status and the COMMAND COMPLETE message and then goes to the BUS FREE phase.
DATA The drive discards the INITIATOR DETECTED ERROR message and sets the
Sense Key to ABORTED COMMAND, sets the Additional Sense Code to INITIATOR DETECTED ERROR MESSAGE RECEIVED. It sends the CHECK CONDITION status and the COMMAND COMPLETE message and then goes to the BUS FREE phase.
STATUS The drive sends a RESTORE POINTERS message, returns to the STATUS
phase, resends the STATUS command, and continues the I/O process.
MESSAGE IN The drive discards the INITIATOR DETECTED ERROR message and sets the
Sense Key to ABORTED COMMAND, sets the Additional Sense Code to INITIATOR DETECTED ERROR MESSAGE RECEIVED. It sends the CHECK CONDITION status and the COMMAND COMPLETE message and then goes to the BUS FREE phase.
4-8 Quantum DLT 4000 Tape Drive
4.2.7 LINKED COMMAND COMPLETE Message (0Ah)
This message is sent from a target to an initiator to indicate that the execution of a linked command (with the FLAG bit set to zero) is complete and that status has been sent. The initiator then sets the pointers to the initial state for the next command.
If received by a target, this message is handled as an illegal message; the drive enters the MESSAGE IN phase and returns MESSAGE REJECT.
4.2.8 LINKED COMMAND COMPLETE, with Flag Message (0Ah)
This message is sent from a target to an initiator to indicate that the execution of a linked command (with the FLAG bit set to one) is complete and that status has been sent.
4.2.9 MESSAGE PARITY ERROR Message (09h)
This message is sent from the initiator to tell the drive that the last message byte the drive passed on to the initiator contained a parity error.
To indicate that it intends to send the message, the initiator sets the ATN signal before it releases ACK for the REQ/ACK handshake of the message that has the parity error. This provides an interlock so that the target can determine which message has the parity error. If the target receives this message under any other condition, it proceeds directly to the BUS FREE state by releasing the BSY signal, signifying a catastrophic error.
Messages
The target’s response to this message is to switch to the MESSAGE IN phase and re-send from the beginning all the bytes of the message that precipitated the MESSAGE PARITY ERROR message.
4.2.10 MESSAGE REJECT Message (07h)
This message is sent from the initiator or target to indicate that the last message received was inappropriate or has not been implemented.
To indicate its intention to send this message, the initiator asserts the ATN signal before it releases ACK for the REQ/ACK handshake of the message that is to be rejected. MESSAGE REJECT is issued in response to any message the drive considers to be illegal or not supported. When sending to the initiator, the tape drive does so before requesting any additional message bytes.
Quantum DLT 4000 Tape Drive 4-9
Messages
4.2.11 NO OPERATION Message (08h)
If a target requests a message, the initiator sends a NO OPERATION message if it does not currently have any other valid message to send. The message is accepted when the drive is acting as a target and may be sent when it is an initiator. If a NO OPERATION message is received during a selection, the drive proceeds to the COMMAND phase (provided ATN does not continue as asserted); the NO OPERATION message is ignored by the tape drive.
4.2.12 RESTORE POINTERS Message (03h)
The RESTORE POINTERS message is sent from the drive to the initiator to direct the initiator to copy the most recently saved command, data, and status pointers for the I/O process to the corresponding current pointers. The command and status pointers are restored to the beginning of the present command and status areas. The data pointer is restored to the value at the beginning of the data area in the absence of a SAVE DATA POINTER message or to the value at the point at which the last SAVE DATA POINTER message occurred for that logical unit.
When the RESTORE POINTERS message is received as a target, the target switches to the message in phase and returns MESSAGE REJECT.
4.2.13 SAVE DATA POINTER Message (02h)
The SAVE DATA POINTER message is sent from the drive to direct the initiator to copy the current data pointer to the saved data pointer for the current I/O process.
When functioning as a target, the tape drive sends this message before a disconnect during a data transfer. It does not send a SAVE DATA POINTER message if it intends to move directly to STATUS phase. When received as a target, it switches to message in phase and returns MESSAGE REJECT.
4.2.14 SYNCHRONOUS DATA TRANSFER REQUEST Message (01h)
This extended message allows the target and initiator to agree on the values of the parameters relevant to synchronous transfers. The tape drive will not initiate the Synchronous Data Transfer Request message; it relies on the initiator to do so. The Synchronous Data Transfer Request command has the format shown in Figure 4-3.
4-10 Quantum DLT 4000 Tape Drive
Messages
Bit
Byte
0 Extended Message Identifier (01h)
1 Length (03h)
2 Message Code (01h)
3
4
7 6 5 4 3 2 1 0
(Figure 4-1)
Transfer Period: Min. = 50 (32h)
Transfer REQ/ACK Offset: Max. = 15
Figure 4–3 Synchronous Data Transfer Request Message - Data Format
NOTE
The tape drive supports initiating synchronous transfer negotiations with the host, but this feature is disabled by default. To enable it, set the MODE SELECT VU ERROM parameter EnaInitSyncNeg.
Quantum DLT 4000 Tape Drive 4-11
Messages
4-12 Quantum DLT 4000 Tape Drive
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