What is Target Mode? | Ciprico Rimfire 3880 manual

Chapter 6 Target Mode Pass-through Commands

Overview of Target Mode

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Overview of Target Mode

What is Target Mode?

Of course, if you are familiar with the SCSI specification, you already know that operation over the SCSI bus takes place between two parties: the initiator of the operation, and the target of the operation. In the SCSI specification, protocol for each party is exactly detailed. A target has certain responsibilities in a transaction, and an initiator has other specific obligations.

Most of this manual has been devoted to describing how the Rimfire 3880 can be used as an initiator on the SCSI bus. This chapter explains how the RF3880 can be used as a SCSI target. It explains a mode of operation for the adapter that is called Target Mode.

The Ciprico implementation of Target Mode on the RF3880 offers flexibility to the person writing a driver for it. The adapter actually makes very few independent decisions. Instead, when acting as a target, transaction information is passed to the Host, and the Host frames the response that the adapter will make as the target. The driver that handles Host business must be written to follow the SCSI specification as well as the Ciprico protocol presented in this chapter.

When Target Mode is enabled, the adapter will accept selections from initiators and initiate reselections. It will also continue to function as an initiator, selecting targets at the request of the Host, and accepting reselections.

Figure 18 RF3880 in Target Mode

User’s Guide

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Ciprico Rimfire 3880 manual What is Target Mode?, Target Mode Pass-through Commands Overview of Target Mode

Contents

Rimfire 3880 Scsi Host Bus Adapter Page Page 21020285 D User’s Guide Preface Organization Initiator Mode Pass-through Commands Describes OrganizationOverview of the RF3880 User’s Guide Notational Graphic ConventionsConventions Graphic Representation of Parameter Block 21020285 D Reference Documents Reference Documents Contents Scsi ID Status Block Format LUN LUN Table of Contents Description of Fields Command Identifier Diagnostic/Self-test 09H Table of Contents Table of Contents Introduction Summary Specifications Index O d u c t O v e r v i e w About Rimfire Design Latest Bus SpecificationsBuffering scheme Product Overview About the Rimfire 3880 Design Buffer Management Target Mode Implementation Product Overview What next? What next? R d w a r e E s s e n t i a l s Introduction SummaryHardware Essentials Introduction Intel 80186XL Hardware Structure DescriptionQLogic FAS Pipelined System Interface Data Buffer Block Diagram Hardware EssentialsGenerator blocks are part of the PSI Choosing an Address Modifier Board AddressingChoosing a VMEbus Address Hardware Essentials Board Addressing Overview of the Ports Hardware Port AddressesHardware Essentials Hardware Ports General Hardware Port Addresses Hardware Essentials Hardware Ports General Hardware Essentials Address Buffer Port Address Buffer PortAddress Buffer Port Writes Address Modifier Field Control Field of Address Buffer Port Hardware Essentials Address Buffer Port Control Field Single Command Structure Address Fields Channel Attention PortHardware Essentials Channel Attention Port Channel Attention Channel Format Status Port Reset Status Port Reset FormatStatus Port Hardware Essentials Status Port Status Port Error Codes Status Port Error Codes Status Port General Status Port General Format Chapter Hardware Essentials Status Port Status Port Catastrophic Error Codes Hardware Essentials Reset Port Reset Port Hardware Essentials Descriptions of Port Usage Descriptions of Port Usage Hardware Essentials R d w a r e Installation Hardware Installation Introduction Overview Installation Process Hardware Installation Unpacking the Board Step Unpacking BoardShipping Damage Unpacking the Board Step Jumpers Termination Hardware Installation Jumpers and Termination Default Jumper Settings Configuration Jumpers Bus Request/Grant and Sysfail Jumpers Bus Request/ Grant Jumper Jumper Sysfail Example Example Base Address Jumper SettingsAddresses For the Address Modifier Jumper Scsi bus Termination Replacement Fuse General Steps Hardware Installation Board Insertion Power-up Sequence Hardware Installation Apply power and observe LEDsMeaning LED’s Error Conditions Hardware Installation Configure and Connect Scsi Devices Step Configure Connect Scsi DevicesSelectable Options Options Cabling Scsi Cable Connector Hardware Installation M m a n d O p e r a t i o n Command Operation Introduction What the Adapter must accomplish Command Operation What the Adapter must accomplish Parameter BaseBlock Parameter Command Descriptor Block Base Status Block Command Operation Base Status BlockStatus Block Format Base Status Block Command Operation Base Status Block Multiple Status Blocks Setting up Unit Options Format Single Command Structure Single Command StructureCommand Operation Single Command Structure Parameter Block Bit-meanings of Interrupt Field Command Operation Single Command Structure Interrupt Command Operation Using a Single Command Structure Using a Single Command Structure Example Start Command List Board-control Some Example Single CommandsCommand Operation Some Example Single Commands Command Identifier = 822F4H Interrupt = 0300H Command = 01H 21020285 D User’s Guide Example Pass-through command PB Example 2Inquiry Pass-through Command Command Operation Command Operation Some Example Single Commands Command List Structure Format Command List StructureDescription of the Fields Number of Status Blocks Number of Parameter BlocksParameter Block Space Status Block Space Command Operation Creating the Command List Structure Creating Command List Structure Command Guidelines Using a Command List StructureCommand Operation Using a Command List Structure Index Guidelines Adding a Parameter Block Removing a Status Block Command Operation Example ‘C’ Routines for Command List Example ‘C’ Routines for Command List Stcdone Command Operation Example ‘C’ Routines for Command List Command Operation I t i a t o r t h r o u g h D e P a s s C o m m a n d s Introduction Summary Initiator Mode Pass-through Commands Introduction Initiator Pass- through Parameter Block Format Command FormatTarget ID Address Modifier Bit-meanings of Flags-1 Field Setting DBV DAT and DIR Bits Using Table Values Example DAT and DIR bit settingsDIR and DAT Settings, Vendor-unique DAT and DIR Automatic Settings Table of DAT DIR Automatic Settings 4EH Initiator Mode Pass-through Commands Flags-2 Bit-meanings of Flag-2 FieldMeaning of TAG Opts Bits Scsi Command Descriptor Block VME Memory AddressTransfer Count Message Format Pass-through Message Parameter BlockMessage Code Description of Fields Scsi Pass-through Status BlockBit-meanings of Flags Field Error Scsi Status Field during Unexpected Scsi Phase Bit-meanings of Scsi Status FieldMeaning of Status Byte Code Meaning of Status Byte Unexpected Phase Three signals. This is described below Default Ordering of Sense Bytes Up to 32 Sequential Sense BytesOrdering of 1st 16 Sequential Sense Bytes Example of Selected Sense Bytes Initiator Mode Pass-through Commands R g e t t h r o u g h D e P a s s C o m m a n d s Target Mode Pass-through Commands Introduction Target Mode Pass-through Commands Overview of Target Mode What is Target Mode? Target Mode Pass-through Commands Adapter must have a means of handling Scsi protocol issuesWhat must the adapter accomplish in Target Mode? New commands Overview Special Target Mode CommandsTarget Mode Enable Command Target Mode Disable Command Scsi Command Descriptor Block Groups Command Descriptor Block Group Codes Command Operation Sequence Events Enabling Target ModeTarget Mode Pass-through Commands Command Operation Sequence Events Receiving a Command From an Initiator Sequence of Events Responding to an Initiator Target Selection Data Structure Target Selection Data Structure Meaning of Flags Field Meaning of Scsi Flags Field Identify Message Received Command Descriptor Block LengthInitiator Identifier Message Bytes Received Semaphore Field Target Mode Response Command Target Mode Response Parameter BlockInitiator ID ⇒ Target Mode Response command Meaning of Response Control Flags Field Status or 1st Message Byte Message Byte Target Mode Response Command Status Block First TM Response Command Status BlockSecond TM Response Command Status Block Meaning of Status Block Flags Field Meaning of Command Status Flags Field Message Byte Received Target Mode Error Sequence Codes A r d c o n t r o l C o m m a n d s Board-control Commands Introduction Board-control Commands Using the Reference Using the Reference General Status Block Board-control Commands General Status BlockGeneral Status Block Format General Status Block List of Commands Board-control Commands List of CommandsBoard-control Commands Start Command List Parameter Block Board-control Commands Start Command List 01HCommand List Memory Address Adapter ID Command Code Board-control Commands Start Command List 01H Interrupt Stop Command List Parameter Block Board-control Commands Stop Command List 02H Board-control Commands Identify 05H Identify Command Parameter BlockIdentify 05H Identify Command Status Block Identify Command Status BlockEngineering Revision Firmware Revision Option Flags Field Identify Status Block Board-control Commands Identify 05H Option FlagsAdapter Scsi ID Bits Day, Month, Year Board-control Commands Board Statistics 06H Board Statistics Command Parameter BlockBoard Statistics 06H Options Field Board-control Commands Board Statistics 06H Options Total Scsi Commands issued to an ID Total Commands ProcessedTarget Mode Selection Count Statistics Data Structure Board-control Commands General Options 07H Command Format Description of FieldsGeneral Options Command Parameter Block General Options 07H Bus Throttle Field Values Bus ThrottleSelect Flags Select Flags Byte Command code for this command is 07H Unit Options Command Parameter Block Board-control Commands Unit Options 08HUnit Options 08H Unit Scsi ID Retry Limit Board-control Commands Unit Options 08H Disconnect Time-outRetry Control Retry Control Select Time-out Unit FlagsUnit Flags Sense Count Initiator Mode Selected Sense Bytes Example Selection of Sense Bytes Example Use of Selected Sense Bytes Fields Board-control Commands Diagnostic/Self-test 09H Diagnostic/ Self-test 09HDiagnostic/Self-test Parameter Block Diagnostics Command Test Flags Field Command code for this operation is 09H Diagnostic Command Status Block Flags ByteBit-meanings of Flags Byte in Status Block Board-control Commands Target Mode Enable 0AH Target Mode Enable 0AHTarget Mode Enable Parameter Block Pointer to the Target Selection Data Structure Meaning of Selection Interrupt Field Board-control Commands Target Mode Disable 0BH Target Mode Disable 0BHTarget Mode Disable Parameter Block Meaning of Flags-1 Field Command Identifier of CMD to be Aborted Board-control Commands Abort 0DHAbort 0DH Abort Parameter Block Scsi Hard Reset 10H Board-control Commands Scsi Hard Reset 10HScsi Hard Reset Parameter Block Board Information 15H Board-control Commands Board Information 15H Board Information Data Structure Board-control Commands Board Information 15H OptionsBoard Information Options Field Board Information Data Structure Board Information Select Flags Field Board-control Commands Board Information 15H Bus Throttle RST Reset Jumper Board-control Commands Board Information 15H Option Flags Board-control Commands Board Information 15H Termination Scsi Cfig BlockAdapter Base Model # Per Target Sense Count Per Target Retry LimitPer Target Device Flags Bit-meanings of Device Flags Field Per Target Synch Period Per Target Selected Sense Bytes Per Target Width Board-control Commands Extended Board Statistics 16H Extended Board Statistics 16HExtended Board Statistics Parameter Block Extended Board Options Field Board-control Commands Extended Board Statistics 16H Options Number of Scsi Parity Errors Total Commands IssuedPer Scsi Target Number of Commands Extended Statistics Data Structure Board-control Commands Per Scsi Target Queue Full CountPer Scsi Target Maximum Queued Board-control Commands Extended Unit Options 18H Extended Unit Options 18HExtended Unit Options Parameter Block Extended Unit Options Data Structure Extended Unit Options Data Structure Description of Fields Bit-meanings of Retry Control Field Unit Flags of Extended Unit Options Board-control Commands Extended Unit Options 18H Unit Flags Board-control Commands Extended Unit Options 18H Selected Sense Bytes T a i l s o f U s a g e Details of Usage Introduction Details of Usage Byte and Word Swapping Need for SwappingExample of Memory Differences Variations in Intel and Motorola Memory Pass-through command Parameters Motorola Ordering Intel Ordering Command Structure Swapping RF3880 Swapping OptionsIntel Ordered Parameter Block Data Swapping Sharing TapesDual Initiators Tagged How to UseQueuing Tagged Details of Usage Tagged Queuing Choose a tag message Meaning of Flags-2 FieldRF3880 sends the tag message Queue Tag Numbers UsageQueue Full Status Message Reject Target Mode Usage Scsi Protocol Handling Scsi Bus Reset HandlingSelection Queue Abort Command Handling Synchronous Data Transfer Requests Target Mode Disable Command Handling Wide Data Transfer Requests Message parity errors Parity error conditionsInitiator-detected Error messages Target Routines Disconnect Privilege Message HandlingMessage Bytes Received from the Initiator 21020285 D User’s Guide User’s Guide 21020285 D Details of Usage Error codes Status Block Error Codes Appendix a Error Codes IntroductionCodes Reported in Status Block and Status Port Error Codes Appendix a Error Codes Summary 2BH Appendix a Error Codes A1H Status Port Error Codes Catastrophic Error CodesAppendix a Error Codes Status Port Error Codes Self-test Error Codes Diagnostic Command 8CH Self-test Status Port Error Codes B l e s a n d C o n n e c t o r s Appendix B Cables and Connectors Introduction Appendix B Cables and Connectors Scsi Connector ConnectorCable Connector Pin-outs for the RF3886 Maximum Cable Length VMEbus Connector Pinouts Appendix B Cables and Connectors VMEbus Connector PinoutsP1 Connector Retry P2 Connector Appendix B Cables and Connectors Specification s Appendix C Specifications Introduction Specifications Appendix C SpecificationsSpecifications for the Rf3880 Appendix C Specifications 21020285 D User’s Guide Fault s Appendix D Defaults Introduction Appendix D Defaults Hardware Defaults Hardware DefaultsHardware Defaults Jumpers Defaults for Hardware Ports Defaults Appendix D DefaultsCommand Defaults TAG Appendix D Defaults S i g n D i f f e r e n c e s Appendix E Design Differences Introduction Appendix E Design Differences Features no longer Supported Features no longer SupportedScatter/Gather Operations Byte and Word Swapping of Data Appendix E Design Differences Implementation Differences Status Port Error Codes and Test FlagsWidth of Data Transfers on the VMEbus Extended Scsi ID’s Scsi Data Widths Block Mode Transfers Odd-byte Addressing How to Maximize Performance D e Index User’s Guide 21020285 D PSI Scsi ID Index Page 21020285 D