Fujitsu 600C manual Selection phase

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4.3.3SELECTION phase

The SELECTION phase allows an initiator to select a target for the purpose of initiating some target function (e.g., READ or WRITE command). During the SELECTION phase the I/O signal is negated so that this phase can be distinguished from the RESELECTION phase.

1.The SCSI device that won the arbitration has both the BSY and SEL signals asserted and has delayed at least a bus clear delay plus a 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.

2.The initiator shall set the DATA BUS to a value which is the OR of its SCSI ID but and the target's SCSI ID bit, and it shall assert the ATN signal.

3.The initiator shall then wait at least two deskew delays and release the BSY signal.

4.The initiator shall then wait at least a bus settle delay before looking for a response from the target.

5.The target shall determine 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 a least a bus settle delay. The selected target may examine the DATA BUS in order to determine the SCSI ID of the selecting initiator; The selected target shall then assert the BSY signal within a selection abort time of its most recent detection of being selected; this assertion is required for correct operation of the selection time-out procedure.

The target shall not respond to a selection if bad parity is detected. Also, if more than two SCSI ID bits are on the DAT BUS, the target shall not respond to selection.

6.No less than two deskew delays after the initiator detects the BSY signal is true, it shall release the SEL signal and may change the DATA BUS. The target shall wait until the SEL signal is false before asserting the REQ signal to enter an information transfer phase.

		SELECTION phase
Bus clear delay	Deskew	Deskew
+ bus settle delay	delay x 2	delay x 2
I/O
BSY
SEL
DB

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Contents Version Page Table of Contents Diagnostics Group 3 error flowchart no paper in ADF paper tray Page General GeneralSystem Block Diagram Device Configuration Outer ViewComponents Functional Specifications Functional Specifications RemarksEnvironmental Specifications Environmental Specifications RemarksOperation Removing the Shipping BracketRemove the shipping retainer Fasten the shipping retainer Power On/Off Indication PanelScsi ID setting Setting the Scsi ID and Connecting the Interface CableNames and functions of the indicators Name Color FunctionScsi Cable Connection Position Paper conditions Paper SpecificationsPaper Size 2.1 ADFFIatbed Items to avoidReadable area ADF readable areaDocument Setting Method When the document size is of letter/A4 size or smallerFlatbed When the document is a thick book Setting the ADF paper chute2 ADF Placing the documents on the ADF paper chute Placing the document on the ADF paper chuteAngling the document sheets Separating the sheets for easy feedingCleaning Cleaning the document cover and the document glassCleaning inside the ADF Page Interface ∙ Busy ∙ Check Condition ∙ Good ∙ Reservation Conflict Physical Specifications Connection1SCSI physical specifications Physical SpecificationSpecifications TerminationSignal Name Pin Number Pin assignmentsScsi Bus System configurationSystem configuration Addresses of Scsi devicesBus signals 2Bus signalsBus signal drive conditions 3Bus phases vs. signal drive sources 1/2Bus Phases Method of driving the interface signalOr connection Nonor connection 5Signal delay times definition Time Definition BUS Free phase Signal delay times definitionTime Definition Arbitration phase BSY Scsi SEL Selection phase Information Transfer phases Information Transfer phase type PhaseDB7 to 9,P Transfer Direction Asynchronous information transfer Asynchronous transfer from target to initiatorAsynchronous transler from initiator to target Commands Relative addressing is not supportedControl byte is not supported Operation Command Code hex Description Reserve Unit commandCommands Bit and field described as Reserved areReserve Unit command Command phase initiator Õ target TP third party ByteTpid third party device ID Byte Release Unit command Release Unit command Command phase initiator → targetTP third party Byte 10 Inquiry command Inquiry commandInquiry command Command phase initiator → target Step Bus phase Initiator operation Target operationEvpd enable vital product data Byte Code ByteCAllocation length Byte Inquiry data Data in phase target → initiator AencColor mode Byte 24, bit 6 to SftRst Soft Reset ByteADF mode Byte 24, bit ISO version, Ecma version, Ansi approved version ByteRequest Sense command Request Sense command Command phase initiator → target11 Request Sense command Allocation length Byte Sense data Data EN phase target → initiatorError code Byte Valid ByteEOM end of medium Byte ILI incorrect length indicator ByteFM file mark Byte Sense key ByteSense Additional Description Send Diagnostic commandCommand-specific information bytes Bytes 8 to B Sense codeSend Diagnostic command Command phase initiator → target PF page format ByteSlftst selftest Byte Test Unit Ready command Contents of self-testResults of self-test Test Unit Ready command Command phase initiator → target AcknowledgmentSET Window command SET Window command Command phase initiator → targetWindow date Data OUT phase initiator → target Transfer Length Bytes 6 toHeader Window descriptor block Auto Byte Y resolution XR, YR Bytes 2 to 3 and 4 toWindow identifier Byte Upper left X,YULX, ULY Bytes 6 to 9, a to DBrightness Byte RemarksBit ordering Bytes 1E to 1F Bit per pixel Byte 1ARIF reverse image format Byte 1D, bit Halftone pattern Bytes lB to 1C lB reservedCompression type, argument Bytes 20 to Update of ScanPartner 600C OEM manual7.4 B&W Scanning Vender unique parameters 18 Vender unique parameters byte 28 and laterPage ADF Byte 2A, Bit Color Scanning Vender unique parameters19 Vendor unique parameters byte 28 and later Source Byte 2A, BitLine width Byte 2D to 2E Highlight value Byte 2BShadow value Byte 2C Line count Byte 2F toObject Position command Object Position command Command phase initator → target Position type ByteBit Count Bytes 2 to Unload objectLoad object NormalRead command Step Bus phase Initiator operation Target operationADF sequence Data type qualifier Bytes 4 to Read command Command phase initiator → targetData type code Byte Transfer length TL Bytes 6 toFor binary data Data in phase target → initiatorImage data Data Type Code = Pixel size data Data Type Code =Scan command Scan Command phase initiator → targetStatus Status phase target initiator Code Status of unitPhase ATN detection timing MessagesATN detection Command Complete X00 Message in phase target → initiator Message typesMessage Abort X06 Message OUT phase initiator → target Message Reject X07 Message IN/OUT phase initiator → targetATN detection phase Action Phase when ATN is detected Action No Operation X08 Message OUT phase initiator → targetBUS Device Reset X0C Message OUT phase initiator → target Message rejected ActionIdendify X80 to XFF Message OUT phase initiator → target Command Sequence Initial sequenceRead sequence Read command sequenceRead sequence for B&W mode Single ReadMultiple Read Status Transition of Logical Unit Error Table Sense keyItems for Specifying Window Page Online diagnostics Ready LED Paper Jam LED Error indicationOnline diagnostics Offline diagnostics Offline diagnostics resultsDiagnostic flowcharts Group 1 error flowchart Lamp assemblyGroup 2 error flowchart Flatbed/ADF motor Group 3 error flowchart paper in ADF paper tray Group 3 error flowchart no paper in ADF paper tray