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Emerson MVME147 manual Initiator Role Custom Packet

Models: MVME147

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Initiator Role Custom Packet

If you suspect data integrity error, you can set up the SCSI script to execute the data phase and then disconnect from the bus (script code 0x2c) or just return as an intermediate return without disconnect from the bus (script code 0x28). Firmware executes the data phase and then returns the firmware parity error status, if any, command packet, and command table back to you.

You can examine the data as well as the firmware status to decide what SCSI status should be returned to initiator. After the status is determined, a new TARGET sequence command packet needs to be sent to firmware with status, message (for message-in phase), and proper scripts to complete the SCSI bus command.

For the previous disk read example, the script would be:

$14,$04,$0C,$10,$18,$00.

The above sequence of codes may be written anywhere in the MVME147- accessible space. It may even be ROMed. The script pointer in the custom SCSI packet is the address of the first entry of the script. In the example, it would point to the $14. Therefore, the message-out phase should always be the first phase in any initiator script.

2.COMMAND TABLE (384 bytes of RAM). The second data structure required by the SCSI firmware for the execution of a custom SCSI packet is a Command Table.

For unsupported controllers, the control of certain functions (parity checking, DMA, linked commands, SCSI rules, DMA scatter/gather, SYNC/ASYNC transfer) is dictated to the firmware through the status/flag byte of the Command Table.

The CDB is one of the pieces of the command table. The user of the initiator role custom SCSI packet loads the CDB to be passed to the SCSI target that is to be selected. The initiator role custom SCSI packet has a Command Table pointer which is the address of the first word of this data structure. Unlike the script, the Command Table must be in MVME147-accessible RAM because the firmware writes to portions of the table. All the user accessible pieces of the Command Table are shown in the following table.

Even Byte \

Odd Byte \

2

2-7

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Emerson MVME147 manual Initiator Role Custom Packet

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 Introduction CUSTOM SCSI PACKETSInitiator Role Custom Packet 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 Control Flags PACKET RETURN STATUSPacket Return Status 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 Introduction TARGET ROLE ROUTINESMVME147 SCSI Firmware Background 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 The table below shows the write filemarks packet Write Filemarks PacketWrite 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 COMMON COMMAND SET AND DISK OPERATIONBYTE OFFSET 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 DescriptorBYTE OFFSET COMMON COMMAND SET AND DISK OPERATIONNOTES 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 DescriptorPage code BYTE OFFSETBYTE OFFSET BYTE OFFSET COMMON COMMAND SET AND DISK OPERATIONNOTES 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