[comp.arch] Lisa Clock Rate

chuck@melmac.harris-atd.com (Chuck Musciano) (03/01/90)

     About a week ago, various posters were discussing the clock rate used
in the original Apple Lisa.  This month's Byte had a pointer to their original
review of the Lisa, so I went back and read the article from just seven years
ago, in the February '83 Byte.  They say (page 43):

	In particular, the 68000 clock was set at 5 MHz instead of the 
	usual 8 MHz to give the hardware just enough time to access the
	32K bytes of screen memory during the machine cycles in whcih the
	68000 is not using the address lines.

     Byte referenced the old issue to point out an interesting statement
by the Lisa designers:

	BYTE: Do you have a Xerox Star here that you work with?
	LARRY TESLER: No, we didn't have one here.  We went to the
		NCC when the Star was announced and looked at it.
		And in fact it did have an immediate impact.  A
		few months after looking at it we made some changes
		to our user interface based on ideas that we got from
		it.  For example, the desktop manager we had before was 
		completely different; it didn't use icons at all, and
		we never liked it very much.  We decided to change ours
		to the icon base.  That was probably the only thing we
		got from the Star, I think.  Most of our Xerox inspiration
		was Smalltalk rather than Star.

Interesting comments, in light of the Xerox/Apple lawsuits now in progress.

     Picking up an old Byte is great fun.  Other highlights from seven years
ago:

	An S-100 64K SRAM board (150 ns 2Kx8 RAMS) went for $629

	Byte discussed this wonderful new standard: NAPLPS
	
	Project of the month: add a reset switch to your VIC-20
	
	Byte reviewed the new Apple IIe, which featured 80 column
	   capability and upper and lower case characters

Chuck Musciano				ARPA  : chuck@trantor.harris-atd.com
Harris Corporation 			Usenet: ...!uunet!x102a!trantor!chuck
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