THE APPLE LISA COMPUTER: A RETROSPECTIVEPART 4 OF 7PROGRAM ANTI-PIRACY AND DATA PROTECTION-------------------------------------------------All Lisas provided a simple and effective method of protectinguser programs from piracy, and data files from overly curiousco-workers.When the user installed a new program, the Lisa "serialized" thedisk copy of the program by writing the ROM-based serial numberto the program floppy disk. The user of this disk would then beunable to copy this "protected master" program file to anotherLisa. The user could still execute the protected program fromthe floppy disk, but this was tedious, given that Lisa programstended to be large and floppy-disk-based program execution wouldtry the patience of most users.Document protection was provided by passwording. The user couldselect a document icon with the mouse and, through a menu-drivendialog, obtain general information about the document. Thisinformation included the document's size and a field for theprotection password. If the user
typed a password into thisfield, the document was protected. When any user attempted toopen a protected document, the Lisa displayed a dialog askingfor the password.NON-PHYSICAL FILE NAMES-------------------------------------------------The Lisa did not display physical file names to the user.Instead the Desktop Manager presented a "document name view"which allowed descriptive names with up to 63 characters. Theunderlying filesystem allowed file names up to 31 characterslong, which could not contain the directory separator character"-". For each document the Desktop Manager maintained a userdocument name (e. g. "Vacation Plans - 1983") and a physicallow-level file name (e. g. "{T3D456}").This non-physical file name scheme allowed the use of multipledocuments with the same user-defined name, whose underlyingphysical file names were different. In this regard the Lisamimicked the physical working desktop, where a worker might havefive photocopies of the same document at the same time.To the best of my knowledge
,
no other currently availablemicrocomputer supports non-physical document names.PULL-OUT HELP CARD IN THE KEYBOARD-------------------------------------------------The Lisa keyboard contained small pull-out firm plastic sheetsof helpful information. The first sheet showed the keyboarditself and a layout of all the keys that the could be typed incombination with the Option key. Other cards gave conciseinformation about Lisa operating features and techniques, suchas how to copy documents. Another blank card allowed users towrite down important personal information pertaining to theLisa; for example, the phone number of the local Apple servicecenter or representative.HARDWARE BASED MEMORY MANAGEMENT-------------------------------------------------The original Lisa contained 1 megabyte of physical memory, withabout half of it used for the Lisa Desktop Manager and theDesktop Libraries. A sophisticated hardware-based memoryvirtualization allowed Lisa programs to access more memory thanwas physically installed. This strategy also allowed the Lisa tosegregate executing programs so that they could not access otherprograms' data at inappropriate times. If memory protection wasviolated, the Lisa would stop the errant application and alertthe user that the program had been terminated.ENVIRONMENTS WINDOW-------------------------------------------------Through the Environments Window, Lisa provided a simple methodfor the computer to run radically different operatingenvironments. On boot-up, Lisa ran a special low-level programcalled the Environment Selector, which located and ran a defaultoperating environment, if one was present. Otherwise, theSelector displayed a window allowing the user to select a run-time environment. Apple supplied two different environments: theOffice System environment for non-technical end users, and theWorkshop environment for programmers. Other companies suppliedadditional environments, e. g. an implementation of UNIX.ADJUSTABLE SCREEN CONTRAST AND DIM DURATION CONTROL-------------------------------
------------------Lisa screen contrast could be adjusted by the user with aspecial program called Preferences. This program also allowedthe user to define a duration of inactivity, after which thescreen would automatically dim and lessen contrast. This featureprevented screen "burn-in," which happens when screen images athigh contrast "burn into" the screen's phosphors. The Lisaautomatically, gradually dimmed the screen in pleasingincrements -- a nice touch on Apple's part which prevented ajarring change in screen brightness and contrast.SCREEN PRIVACY FEATURE-------------------------------------------------For users who dealt with sensitive data, the Lisa provided asimple screen privacy feature. The user could press Option-Shift-[numeric keypad zero] at any time and the screen wouldimmediately dim.SELF-TEST AND FOREIGN LANGUAGE USAGE VIA THE ATTACHED KEYBOARD-------------------------------------------------The Lisa, when powered on, ran a special hardware self-testwhich made certain that it could safely run user programs andmanipulate user data. Hardware failure would trigger a specificfailure error number which could be used by an Apple servicecenter to isolate the defective part.During these diagnostic tests (which took around 3 minutes toexecute) the Lisa displayed icons and messages to the user. Themessages could appear in either English, French, or German,according to which keyboard was attached; Lisa keyboards wereself-identifying and provided the Lisa with informationincluding the keyboard "language". For example, if the keyboardwas a German keyboard, then all diagnostic messages appeared inGerman.Unfortunately, this language-sensing compatibility didn't extendto the menus of Office System applications and programs likeLisaWrite!SPECIAL SERVICE MODE-------------------------------------------------Lisa firmware contained a "service mode" which could beactivated when the computer was powered on; this special featureallowed the knowledgeable user to run additional diagnostictests. Also supported was a cross
-hatch display pattern whichmade it easier to adjust the screen contrast.EASY SYSTEM DISASSEMBLY-------------------------------------------------Any subassembly of a Lisa, except for dangerous portions likethe monitor CRT, could be disassembled by the end-user, readilyand with few if any tools. For example, users could remove andreplace a disk drive with ease by just gripping the tabs at thebase of the front panel, popping the front off, and unscrewing asingle screw which held the drive in place.MACINTOSH XL, MACWORKS, LISA-TO-MAC MIGRATION KIT-------------------------------------------------When Apple planned to discontinue Lisa, the company was leftwithout a high-end system. All Apple had to offer at the timewas the Macintosh 128K or 512K models, which were more compactthan the Lisa but lacked the appeal of its bigger screen, biggermemory, and hard disk.Apple's hardware and software engineers quickly developed aspecial program named MacWorks that allowed a Lisa owner to turnthat computer into a "big" Macintosh. Apple produced threeversions of MacWorks before turning over all MacWorksdevelopment to Sun Remarketing (see endnote).Apple combined the new MacWorks with a renamed Lisa called theMacintosh XL. This gambit sold a rather surprising (to Apple)number of Lisas. MacWorks is still a commercial product for SunRemarketing, which went on to develop an enhanced MacWorks Plusthat lets a Lisa emulate a Macintosh Plus. (I wonder how manyLisas/Macintosh XLs Sun really sells now, but the company hasbeen prodigious in developing and producing XL hardwareperipherals, including larger hard disks and a board that allowsSCSI devices to work with the XL.)Apple solved the problem of transferring Lisa data to aMacintosh with the Macintosh XL Migration Kit, consisting of aspecial Lisa program called Lisa-to-Macintosh and a set ofMacintosh data conversion programs. The Lisa program (primarily)wrote Lisa data files to a Macintosh disk; the Macintosh dataconversion programs took the resulting files and converted themto Macintosh
data files in an appropriate format. For example,LisaWrite documents could be converted to either MacWrite orMicrosoft Word files for use by the Macintosh.END OF PART 4
> Regards,
> David T. Craig
>
> ###########################################################
> # David T. Craig -- CyberWolf Inc. -- ACI 4D Developer #5
> # Aspen Plaza, 1596 Pacheco, Suite 203
> # Santa Fe, NM 87505 USA
> # voice 505.983.6463 ext 15 -- fax 505.988.2580
> # dcraig_at_email.domain.hidden
> ###########################################################
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