Driver:	TWTMC, Version 4.10.00 January 30, 1993
	Copyright (c) 1990-1993, Emeritus Technologies.
	All rights reserved.

	TapeWare Future Domain TMC-1800 Controller Driver

	Date		Mod	Description
	-------------	---	-----------------------------------------------
	20-Jul-1992	MDB	Created this driver.

	19-Aug-1992	MDB	First release of beta version.

	20-Aug-1992	MDB	Since the TMC-1800 does not use DMA,
				it can not access memory above the
				1Mb boundary. Therefore, TapeWare must
				be informed that it must allocate its
				tape buffer in REAL memory when
				running under DOS. 

	4-Sep-1992	MDB	SEL_TIMEOUT value had to be increased due to
				erroneous time-out errors when operating on
				some of the faster machines.

	8-Sep-1992	MDB	Corrected problem in ISR that was causing us
				to intermittently miss the MESSAGE_IN IRQ
				following STATUS phase.

				Added the following parameters to the command
				line:

					SEL_TIMEOUT (default: 3500)
						Controls the time-delay during
						a device selection phase
						before the driver reports a
						device can't be located.

					BUS_SETTLE  (default: 50)
						Controls the time-delay that
						the SCSI bus must be free
						before a selection phase may
						begin.

					REQ_TIMEOUT (default: 250)
						Controls the retry/wait period
						during a command phase before
						the driver reports a device
						responce failure (Controller
						Specific Error 1.)

	9-Sep-1992	MDB	Masked out our IRQ line on the 8259 controller
				during interrupt processing. This allows the
				Future Domain controller to signal another
				interrupt without the 8259 attempting to
				process it until the IRQ line has been enabled
				again.

	16-Sep-1992	MDB	Corrected a bug in the device selection routine
				that was causing some devices to ignore the
				selection phase.

	17-Sep-1992	MDB	Corrected a bug in the command phase processing
				that was forcing an abort of a command if the
				command req/ack cycle was too long. The problem
				was not in aborting the command but rather in
				properly re-initiating it afterword.

	19-Sep-1992	MDB	Changed code in interrupt service routine to
				force re-arm of interrupt on request timeout.

	24-Sep-1992	MDB	Disabled interrupt generation on controller
				before signaling EOI. Enable interrupts on
				controller upon ISR exit.

	30-Jan-1993	RAC	Cleaned up submit and processing, removed
				DEVLOAD command.

