Emerson MVME147 manual Attach/Detach Packet all devices, Command

Attach/Detach Packet (all devices)

	COMMAND	CONTROLLER
DEVICE	NAME	COMMAND	NOTES
TAPE	Rewind	$01	A rewind command is sent (2.0
			firmware and later) because
			many tape devices require the
			tape to be at BOT to send a
			mode select command.
	Reserve device	$16	Executed on attach if reserve-
			on-attach/release-on-detach bit
			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.
	Mode select	$15	This command configures the
			controller for operat-ional
			parameters.
	Test unit ready	$00	Checks whether the selected
			device is ready.

An attach is required before any other commands may be sent to the SCSI firmware (except custom SCSI sequence or Bus Reset).

An attach call initializes the SCSI firmware pointers and internal flags. A RAM work area is used by SCSI firmware for building internal pointers and also contains the command sent to the SCSI controller. The RAM work area should not be reallocated until the device is detached or reset.

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