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Emerson MVME147 manual

Models: MVME147

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Initiator Role Custom Packet

controller following a check status and

a request sense data command. Valid

information if bit 14 (additional status)

				is set.
				This block is
				firmware private area
				and only
				used on the
				INITIATOR role.
.			.
.			.
$9E		xxxxxxxx	xxxxxxxx	Sense data block
NOTE	1.	Points to scatter/gather table if scatter/gather bit = 1 in byte 0.
S:

2.If = 0 and if status is "check", SCSI firmware interprets returned SCSI status, and sends a request sense command to the controller; if status is = busy, infinite retries are performed. If = 1, SCSI firmware does not read the SCSI status from the command table, and returned status word in the packet reflects only firmware status.

3.Must be 0. MVME147 SCSI firmware ONLY supports SCSI devices.

4.In TARGET mode, the CDBs is received from the SCSI bus and it will be returned to the user without any modification with CDB length. When a target LUN is not enabled or when ’target device reset’ or ’abort’ message is received, the CDB received by the target role firmware will not be returned to the user. Instead, a error code will be returned.

Example: Sending linked commands to a disk controller

You intend to implement a read-modify-write function for your particular operating system. The benefit of linking commands on the SCSI bus is a better utilization of bus bandwidth. When two commands are linked, the TARGET does not disconnect between commands. After the message-in phase completes one command, the TARGET switches to command phase for the second command. The arbitration and selection phases are eliminated for the

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Emerson MVME147 manual

Contents

GENERAL INFORMATION FeaturesIntroduction Modes of OperationMVME147 SCSI Firmware Entry Points The SCSI firmware initializes these vectors Equipment Supported CONTROLLE CONTROLLE CONTROLLEDEVICE PARTCONTROLLE Devices Supported Under Common Command SetDEVICE PARTMOTOROLA Related DocumentationDOCUMENT TITLE PUBLICATION NUMBERMOTOROLA Manual TerminologyGENERAL INFORMATION Initiator Role Custom Packet CUSTOM SCSI PACKETSIntroduction CUSTOM SCSI PACKETS Initiator Role Custom Packet NOTES PHASE PHASE CODEInitiator Role Custom Packet +$00 +$68 status Note ASYNC the firmware status xxxxxxxx xxxxxxxx Page CUSTOM SCSI PACKETS Initiator Role Custom Packet CUSTOM SCSI PACKETS TARGET Enable Custom Packet TARGET Enable Custom PacketStatus from SCSI NOTESTARGET Enable Custom Packet TARGET Sequence Custom Packet TARGET Sequence Custom Packet NOTES CUSTOM SCSI PACKETSTARGET Sequence Custom Packet WORDS $04 and $06 CUSTOM SCSI PACKETS TARGET Sequence Custom Packet CUSTOM SCSI PACKETS RETRY COUNT. Not used by the TARGET role firmware TARGET Sequence Custom PacketCUSTOM SCSI PACKETS Packet Return Status PACKET RETURN STATUSControl Flags SCSI 1 = Retries were performed Bit 5 COMMAND RE Bit 3 FM Filemark Bit 4 COMMAND RETRYThe command was retried retry count times Packet Return Status Bit 2 EOM End of mediaPACKET RETURN STATUS Intermediate Return Table 3-1.Packet Status CodesCodes CODETable 3-1.Packet Status Codes Final Return CodesCODE Intermediate ReturnSCSI Bus Reset Packet section in Chapter Table 3-2.Packet Status Codes cont’dCODE MEANINGTable 3-3.Packet Status Codes cont’d Request-Sense-Data Error-Class7 CodesController-Dependent CODETable 3-4.Packet Status Codes cont’d SCSI Status Returned in Status PhaseCODE MEANINGTable 3-5.Packet Status Codes cont’d Request-Sense-Data Error-Class0 through 6 CodesCODE Controller-DependentPage PACKET RETURN STATUS SCSI Firmware Interrupt Structure SCSI FIRMWARE INTERRUPT STRUCTURESCSI FIRMWARE INTERRUPT STRUCTURE SCSI_CMD WRITING A DRIVERSCSI_ACTV SCSI_INTBuilding the Packet Passing Commands to the SCSI FirmwareInterface Rules for the SCSI Firmware Figure 5-1.SCSI Disk Driver Interface to VERSAdosInterface Rules for Multiple Callers WRITING A DRIVER Care must be taken not to modify the contents of WRITING A DRIVER Interface Rules for the SCSI Firmware FUNNEL WRITING A DRIVER Interface Rules for the SCSI Firmware WRITING A DRIVER MOVE.W 2A2,D0 THE CODE BELOW HANDLES FINAL RETURN CODES Interface Rules for a Single Caller WRITING A DRIVER MVME147 SCSI Firmware Background TARGET ROLE ROUTINESIntroduction Custom Sequence Packet SCSI Versus SASI RulesScript Command TableEnabling TARGET Role Enabling TARGET Role Servicing the TARGET Requests Servicing the TARGET Requests TARGET ROLE ROUTINES Servicing the TARGET Requests TARGET ROLE ROUTINES Servicing the TARGET Requests TARGET ROLE ROUTINES Table 7-1.SCSI Functions SCSI PACKETSIntroduction SCSITable Read/Write PacketSCSI Functions cont’d SCSIDISK and TAPE Controller logical unit in SG table, if zero Old Packet Supported for Compatibility SCSI PACKETS+$12 in SG table, if zero Read/Write Packet DMA Scatter/Gather Table Entry|function code 3 bits 1 = link to next entryFor example $5 isAttach/Detach Packet all devices COMMANDCOMMAND CONTROLLERAttach/Detach Packet all devices COMMANDSCSI PACKETS +$1E FM encoding, single Controller type refer xxxxxxxx attributes byte offset +$20 Single track density Drive type 0 = Example for floppy Attach/Detach Packet all devices3½, 5¼ 3½, 5¼,3½, 5¼, 3½, 5¼3½, 5¼ 3½, 5¼+$04 Minimum read QIC-24 if this is set to 0, the +$00 Reserved Interrupt level +$00 +$9E $00 Format Packet COMMAND Assign Alternate Sector Packet SCSI+$0E Assign Alternate Sector Packet SCSI DEFECT LIST TYPE SCSI PACKETS0 Note 3, Head Bytes from Index MSW Note NOTESSCSI Bus Reset Packet Controller logical unit Erase Packet SCSI Controller Reset Packet+$12 Rewind Packet Device logical unit Read Block Limits Packet SCSI PACKETS where n = number of blocks or filemarks to Space Status from SCSI Write Filemarks Packet Write Filemarks PacketThe table below shows the write filemarks packet Controller logical unit Verify CRC Packet The controller must be in general or read modeTape Mode Select/Sense Packet Tape Mode Select/Sense Packet Number of tracks on Inquiry Packet +$00 Reserved +$1A Load/Unload Packet +$14 Recover Buffer Data Packet +$0C Request Sense Data Packet Controller logical unit Check Status Packet SCSI PACKETS Open PacketOpen Packet SCSI PACKETS BYTE OFFSET COMMON COMMAND SET AND DISK OPERATIONBYTE BYTE OFFSET BYTEBYTE OFFSET BYTE OFFSET ENTRY NUMBERNOTES COMMON COMMAND SET AND DISK OPERATIONSend mode select command COMMON COMMAND SET AND DISK OPERATION DEFECT LIST TYPE DEFECT LISTBYTE OFFSET NOTESBYTE OFFSET Mode Select HeaderBYTE OFFSET BYTE OFFSET Block DescriptorNOTES COMMON COMMAND SET AND DISK OPERATIONBYTE OFFSET BYTE OFFSET Mode Select HeaderBlock Descriptor BYTE OFFSETBYTE OFFSET BYTE OFFSETNOTES VALUEBYTE OFFSET Mode Select Command CDBVALUE COMMENTSMode Select Header COMMON COMMAND SET AND DISK OPERATIONBYTE OFFSET Block DescriptorBYTE OFFSET BYTE OFFSETPage code NOTES COMMON COMMAND SET AND DISK OPERATIONBYTE OFFSET MEDIA ATTRIBUTE FLAGSTYPE Mode Select HeaderATTRIBUTE FLAGS COMMON COMMAND SET AND DISK OPERATIONMEDIA TYPEBYTE OFFSET BYTE OFFSETNOTES VALUECOMMON COMMAND SET AND DISK OPERATION PIN 34 CONTROLPin 2 and Pin 34 Definition for High Density Pin 2 and Pin 34 Definition for Low DensityPIN 2 CONTROL PIN 34 CONTROLCOMMENTS Pin 34 = driveA-22