Responding message requirements | Seagate Ultra 160, Ultra 320

Table 11:	Negotiable fields and effects of successful negotiation

				Negotiation message pair

Field name			PPR	WDTR	SDTR


		PCOMP_EN	Negotiated	Sets to 00h	Sets to 00h

		RTI	Negotiated	Sets to 00h	Sets to 00h

		RD_STRM	Negotiated	Sets to 00h	Sets to 00h

Protocol		WR_FLOW	Negotiated	Sets to 00h	Sets to 00h
Protocol
options		HOLD_MCS	Negotiated	Sets to 00h	Sets to 00h

		QAS_REQ	Negotiated	Sets to 00h	Sets to 00h

		DT_REQ	Negotiated	Sets to 00h	Sets to 00h

		IU_REQ	Negotiated	Sets to 00h	Sets to 00h

When negotiating, the responding port shall respond with values that are a subset of the values in the originat- ing message as indicated in Table 12 (e.g., if the originating message requests a REQ/ACK offset of 10h, the responding message has a REQ/ACK offset field set to 10h or lower).

Table 12:	Responding message requirements
			Response shall be
Field Name		Message	numerically


Transfer Period Factor		PPR, SDTR	Greater than or equal

REQ/ACK Offset		PPR, SDTR	Less than or equal

Transfer Width Expo-		PPR, WDTR	00h or 01h
nent

	PCOMP_EN	PPR	Less than or equal

	RTI	PPR	Less than or equal

	RD_STRM	PPR	Less than or equal

Protocol	WR_FLOW	PPR	Less than or equal
Protocol
Options	HOLD_MCS	PPR	Less than or equal

	QAS_REQ	PPR	Less than or equal

	DT_REQ	PPR	Less than or equal

	IU_REQ	PPR	Less than or equal

Parallel SCSI Interface Product Manual, Rev. A )

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Seagate Ultra 160, Ultra 320 manual Responding message requirements, Response shall be, Field Name Message Numerically

Contents

Parallel Scsi Interface Page Parallel Scsi Interface Page Revision Date Writer/Engineer Revision status summary sheet Parallel Scsi Interface Product Manual, Rev. a Table of Contents Parallel Scsi Interface Product Manual, Rev. a Wide transfer Logical characteristics Message system specification Scsi commands Miscellaneous Scsi bus characteristicsSPI information units Drive features List of Figures Xii Parallel Scsi Interface Product Manual, Rev. a Interface requirements How to use this interface manual Scope of Scsi standards Applicable standards General interface description Scsi client-server model GlossaryPage Page Page Page Page Page Keywords Summary of Scsi messages Physical interface characteristicsMessage Name Hex Code Number Scsi bus Priority Scsi IDs and associated Scsi bus arbitration priorities Scsi bus signals overview Scsi target usage of Pcrca Pcrc signal usage requirements LVD signals Signal statesSignal values SE signals Voltage and current definitions OR-tied signals DB7-0 Signal sourcesSignal sources Data bit P cable Data bit a cable I/O DB15-8 Scsi bus phase Reference Type Value ns Unless Timing description Scsi bus timingScsi bus control timing values in nanoseconds Timing Timing values for negotiated transfer rate in nanoseconds Scsi bus data and information phase ST timing valuesTiming values for negotiated transfer rate Nanoseconds unless otherwise notedPage ATN transmit setup time Min Receive Scsi bus data and information phase DT timing values Fast-160 Fast-320 Comments Total transmitter error budget Receiver errorsInterconnect and system margin ISI of data ATN transmit setup timeATN receive setup time Crosstalk time shift Bus settle delay Bus clear delayBus free delay Bus set delay PCRC transmit setup time Flow control receive setup timeFlow control transmit setup time PCRC receive setup time QAS arbitration delay Data release delayPhysical disconnection delay Power on to selection Receive negation period Receive internal setup timeReceive setup time Receive internal hold time Residual skew error Reset delayReset hold time Reset to selection System noise at launch System deskew delaySkew correction range Strobe offset tolerance Measurement points LVD measurement points Clocking methods for data transfers ST latching data vs. DT latching data DT synchronous transfer example Paced transfer on a Scsi bus Paced transfers Data transfer modesAsynchronous transfers Synchronous transfers Information unit transfers ST Data phase parallel transfersDT Data phase parallel transfers Data group transfers Negotiation algorithm Negotiation Negotiation message pair Field name When to negotiateNegotiable fields Negotiable fields and effects of successful negotiation Response shall be Responding message requirementsField Name Message Numerically Transfer agreements Synchronous Transfer period factorTransfer period factor relationships Value Description Message Transfer rate Transfer width exponent 12.6 REQ/ACK offset Protocol options bits Protocol optionsIureq PPR negotiation keeping Iureq set to zero Bus phases resulting from Iureq changesSdtr negotiation PPR negotiation setting Iureq to one PPR negotiation setting Iureq to zero Pcompen WrflowRdstrm RTI Retain Training Information Transfer Negotiable field combinationsTransfer Period Negotiation message sequences Message restrictions Parallel Scsi Interface Product Manual, Rev. a BUS Free phase Scsi bus phases overviewUnexpected and expected bus free phases Arbitration and QAS overview Expected bus free phases Normal Arbitration phase QAS protocol QAS phase overview Selection phase Information unit transfers enabled Information unit transfers disabledSelection overview Selection using attention condition timeout procedure Reselection phase overview Reselection phasePhysical reconnection Scsi bus fairness Physical reconnection timeout procedure Information transfer phases Information transfer phasesSignal Phase Direction of transfer Comment Synchronous transfer Asynchronous transferST synchronous data transfer Information unit transfer DT synchronous transferPage Data group data field transfer Page Page Page Paced transfer training pattern Paced transfer Start of section a DT Data in phase training patternStart of section B Start of section C DT Data OUT phase training pattern 3.2 P1 data valid/invalid state transitions Starting pacing transfers with no training pattern Starting pacing transfers at end of training pattern Paced information unit transfer Ending pacing transfers Wide transfer Deskewing Data phase Command phase Message phase Status phase Message OUT phase exception condition handling Signal restrictions between phasesMessage in phase exception condition handling Message OUT phase Scsi bus phase sequences overview Scsi bus phase sequences Hard reset or protocol error Reselection Selection Arbitration DT Data Message OUT Data bus protection overview ST data bus protection using parityParity checking rules for Selection and Reselection phases Data bus protection Order of bytes in the CRC field Error detection capabilities Message formats General message protocols and formats Extended messages Message formatOne-byte messages Two-byte messages Extended Message Codes Message categoriesLink Control Messages Link Control message codes Key Bit Byte DisconnectIdentify Identify message format Invalid data bits Ignore Wide ResidueIgnore Wide Residue message format Ignore field definition Message Reject Initiator Detected ErrorLinked Command Complete Message Parity Error Modify Bidirectional Data Pointer Modify Data Pointer message format No Operation Modify Bidirectional Data Pointer message format Parallel Protocol Request message format Parallel Protocol Request Value 00h 01h-FEh FFh Description Timing values Valid protocol options bit combinations Use ST Data in and ST Data OUT phases to transfer dataUse QAS for arbitration Parallel Protocol Request messages implied agreement QAS Request Restore PointersSave Data Pointers Synchronous Data Transfer Request message format Synchronous Data Transfer Request Sdtr messages implied agreements Initiator initiated Sdtr negotiation Target initiated Sdtr negotiationTask Complete Wide Data Transfer Request message format Wide Data Transfer Request Target initiated Wdtr negotiation Wdtr message implied agreementResponding Scsi device Wdtr response Implied agreement Task attribute message overview and codes Task attribute messages ACA Auto Contingent Allegiance Task attribute message codesACA message format Ordered Head of Queue 0Eh Task management messagesTask management message codes Task management message codes Abort Task Clear ACA Logical Unit ResetTarget Reset Abort Task SET Miscellaneous Scsi bus characteristics Hard reset Bus reset condition Asynchronous condition recovery Reset events Saved pointers Active pointers Asynchronous event notification Command processing considerations and exception conditionsIncorrect initiator connection Unexpected Reselection phase Information unit transfer logical operations SPI information unitsPage Parallel Scsi Interface Product Manual, Rev. a 115 116 Parallel Scsi Interface Product Manual, Rev. a Parallel Scsi Interface Product Manual, Rev. a 117 SPI information units SPI command information unit SPI command information unit Bit Byte Task Management flags Codes Description Task Attribute Codes Description SPI LQ information unit Bit Byte SPI LQ information unit Bidi Direction FFh All SPI LQ information unit typeCodes Type Description F0HPage SPI data stream information unit SPI data information unitSPI data information unit Bit Byte SPI status data stream information unit Bit Byte SPI status information unit Bit Byte SPI status information unitReserved Reserved for FCP Task management function not supported SPI command information unit fields invalidPacketized Failures field Bit Byte Packetized Failures code Codes DescriptionPage 130 Parallel Scsi Interface Product Manual, Rev. a Command Descriptor Block CDB Command implementation requirementsReserved Page Fixed and variable length Command Descriptor Block formats Typical CDB for 16-byte commands Bit Byte Typical CDB for 12-byte commands Bit ByteAdditional CDB Data if required Additional CDB Length n-7 Typical variable length CDB Bit Byte Operation Code 7FhPage Naca a Control field Bit Byte LastLink b Status Status precedence Single command example Command examples Disconnect example Disconnect example Auto Contingent Allegiance or Contingent Allegiance Timing examples Clearing an Auto Contingent Allegiance condition Overlapped commands Sense data Incorrect logical unit selectionAsynchronous Event Reporting Autosense Unit Attention condition Untagged task queuing Target hard resetLogical unit reset Queued tasks formerly queued I/O processes Tagged task queuing Programmable operating definition Parameter rounding Incorrect initiator connection Short and extended self-tests Default self-testS.M.A.R.T. system Self-test operations Background mode Foreground modeSelf-test modes Device type a Command Reference All device types Exception commands for background self-tests Error detection for asynchronous information phases Self-test mode summaryProtection code Word Location Signal Meaning Covered signalsPage Code description Error detection propertiesProtection code usage Disabling protection code checking Error handlingProtection code transmission Enabling protection code checking Case 1-Power off during removal or insertion SPI-3 to SCSI-2 terminology mapping SPI-3 to SCSI-2 terminology mappingSPI-3 equivalent term SCSI-2 term Index Code value reserved Disconnect privilege 148 domain 5, 9 dormant Initiator 3, 6, 14, 131, 140 faulted Multidrop 7 multimode Page Scsi Page Wdtr 40 170 Parallel Scsi Interface Product Manual, Rev. a Page Seagate Technology LLC