Emerson MVME147 manual The SCSI firmware initializes these vectors

Models: MVME147

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The SCSI firmware initializes these vectors.

MVME147 SCSI Firmware Entry Points

6.$FFFE079A (RTE entry)

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Note

Within the SCSI firmware, which can stand alone without the debug monitor, the first six longwords are the branch table entries referenced above. The hex offsets provided reside within the non-volatile RAM.

The following are descriptions of the six entry points. For more detailed descriptions of their use, refer to the Interface Rules for Multiple Callers section in Chapter 5.

$FFFE077C: COMMAND ENTRY Branches to FUNNEL entry.

$FFFE0782: REACTIVATION ENTRY

Branches to FUNNEL entry. All preprocessed commands are activated in the interrupt service routine through software interrupt.

$FFFE0788: INTERRUPT ENTRY

This entry point is used as the interrupt service routine address for vectors on the MVME147 module. Vector $45 (offset $114 from VBR) is the WD33C93 interrupt vector used by the SCSI firmware. Vector $46 (offset $118 from VBR) is the DMA channel interrupt vector and vector $4B (offset $12C from VBR) is the software interrupt vector used by the SCSI firmware to service queued commands.

Note

The SCSI firmware initializes these vectors.

The following intermediate return resumes with an interrupt which gives

control to the interrupt entry:

$02: WAIT FOR INTERRUPT (OPEN)

Intermediate status indicating that an WD33C93 interrupt brings the processor control back to the SCSI firmware. The MVME147 can accept more commands if it is currently disconnected from the SCSI bus (refer to the SCSI Firmware

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Emerson MVME147 manual The SCSI firmware initializes these vectors