Emerson MVME147 manual Attach/Detach Packet all devices, Command, Controller, Device, Name, Notes

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SCSI PACKETS

NOTES: There may be any number of scatter/gather entries.

The scatter/gather table must be in local MVME147 RAM (the DMA channel does not table walk offboard RAM).

Table address must be longword aligned.

Attach/Detach Packet (all devices)

For common command set refer to Appendix A. The following SCSI commands are executed during an attach:

	COMMAND	CONTROLLER
DEVICE	NAME	COMMAND	NOTES
SCSI	Reserve device	$16	Executed on attach if reserve-
Wincheste			on-attach/release-on-detach bit
r			is set in packet. A reserve
			device command is sent to the
			controller. A reserve device
			command can be used in a
			multi-initiator SCSI environ-
			ment to reserve the device.
	Release device	$17	Executed on detach if reserve-
			on-attach/release-on-detach bit
			is set in packet. A release
			device command is sent to the
			controller and the firmware
			clears an internal attach flag. A
			release device command can be
			used in a multi-initiator SCSI
			environment to release the
			device.
	Test unit ready	$00	Checks whether the selected
			device is ready.
	Mode sense	$1A	To check the block size. If the
			block size in the packet is
			different than the
			controller/drive setting, all
			reads/writes are blocked and
			an "attach error" is returned.

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