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What SGI hardware to we have?
	Multibus vs. VME bus.
	UNIX processor and software.

What do we need to do LISP development for the new SGI color product?
	LISP software to communicate:
	  (a) directly with new SGI color system.
		1. character stream; no graphics for console operation
		2. same functionality as current window system; bit-map display
		3. new window system, non-bit-mapped display
		4. provide window or sharing capability for MIPS UNIX
	  (b) through MIPS UNIX.
		1. UNIX shares whole color device.
		2. UNIX provides window for LISP; character stream only
		3. UNIX provides window; LISP graphics in window

What do we need to do IOP software development?

For MIPS UNIX development?

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Bobp, 10/9/86

Problem:
	Minimize cost and complexity for LISP and UNIX in SGI box.

Factors:

SGI box.
	One or two K processors.
	May or may not have SGI color board set.
	May or may not have MIPS UNIX board.
	May or may not have IOP.
	SCSI bus, possibly multi-master for IOP and MIPS to share.

LMI K processor in SGI box.
	One or two K processors in LMI product.
	May have to consider K processor upgrade to existing
	SGI MIPS/color system.

LMI IOP.
	Only source of B/W graphics.
	LISP TCP and CHAOS will assume presence of IOP; use of MIPS
	board for net will add 2-3 months software work (LISP and MIPS).

	In multi-processor system, IOP should do all I/O, but first-pass
	IOP software only supports one processor.

MIPS UNIX board.
	Runs UNIX; has SCSI and network interfaces that UNIX uses.

	MIPS UNIX assumes it is sole user of I/O devices.  For MIPS
	board to do disk and net I/O for K requires 2-3 months work.

	UNIX has hairy graphics interface for SGI color hardware.
	Big problem (3-6 months) to create software for K and MIPS
	to really share the color hardware.

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Functionality issues:

IPC:
	(shared-memory stuff)

DISK:
	IOP only
	MIPS only
	multi-master SCSI
	K through MIPS vs. MIPS through IOP

COLOR:
	Controlled by MIPS and/or K.
	K uses as system console
	K uses as second screen
	window system?
	supdup from MIPS UNIX?
	stream output only, from LISP?

NET:
	MIPS and IOP have hardware.
	Two transceivers for one box?
	MIPS UNIX uses IOP?
	K LISP TCP uses MIPS?

LISP CONSOLE:
	real window system on SGI color?
	always require B/W per K?
	Boot K (possibly just coprocessor) w/o console device?
	K uses supdup from MIPS UNIX?

----------------

Possible configurations:

(1):	IOP and K; SGI color optional.

(2):	MIPS UNIX and K; SGI color required.

(3A):	MIPS, IOP and K; SGI color may be optional or required.
	MIPS does all disk, tape and net I/O.
	IOP present only for B/W screens.

(3B):	MIPS, IOP and K; SGI color optional.
	IOP does all disk, tape and net I/O.
	MIPS UNIX modified to do I/O through IOP.
	Who has control of SGI color?
	MIPS UNIX booted by serial port, supdup from K, or SGI color console?

(4):	MIPS, IOP and K; SGI color required.
	MIPS and IOP share multi-master SCSI bus.
	Disk drives allocated per-processor; tape shared in software.
	Two ethernet transceivers.
	MIPS UNIX minimally modified; does all I/O itself.
	IOP software not modified; does all I/O for K.

(5):	K 2x2: IOP and 2 K processors; MIPS and/or SGI color optional.
	....