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The Apple --desktop technology arrives for under $2500 by Gregg Williams Apple established itself as one of strengthened that reputation with a The Macintosh arrives, finally, after the leading innovators in personal new machine, the Macintosh (above). a history of colorful rumors. It will computing technology a year ago by In terms of technological sophistica- cost from $1995 to $2495, weighs 22.7 introducing the Lisa, a synthesis and tion and probable effect on the mar- pounds, and improves on the mouse- of human-interface tech- ketplace, the Macintosh will outdis- window-desktop technology started nology that has since been widely tance the Lisa as much as the Lisa by the impressive but expensive Lisa imitated. Now the company has has outdistanced its predecessors. computer. A system with printer and

30 February 1984 C BYTE Publications Inc. second disk drive costs about $900 corner are selections for the current commercial product: the / , but even at that price, the line width. By selecting the "open mouse orientation, the desktop meta- Macintosh is worth waiting for. oval" tool and the thickest line width, phor, the data-as-concrete-object we can draw empty ovals with thick metaphor, and the shared user inter- The Macintosh at Work borders (figure 1d). By selecting the face between programs. The Mac has Before we look at the Macintosh (or "paint bucket" tool and the "diagonal inherited these concepts; for further Mac) in more detail, lets look at how bricks" pattern, we can fill the oval details on them, see my article, "The it works. When you turn the Mac on, with that (figure le). The Lisa Computer System" (February 1 its screen tells you to insert a 3 /2-inch "eraser" tool lets us erase part of the 1983 BYTE, page 33). Sony . When you do that, image (figure 1f); for finer control, we Four differences between the Lisa the Macintosh puts a disk on the can give the FAT BITS command and the Mac make the latter a screen along with the disks name. As (figure 1g), which allows us to erase second-generation computer. First, with the Lisa computer, you first or paint on a -by-pixel basis. the Mac runs at a higher clock speed, select an object, then choose a menu When we are finished with our im- 7.83 MHz (compared to the Lisas 5 item that works on the object. Say, for age and select the QUIT command, MHz). Second, the Mac, which has example, we choose the disk by mov- the program displays an alert box that a smaller amount of memory to work ing the cursor to the disk icon and asks if we want to save our changes with than the Lisa, uses its memory clicking the once (figure 1h). more efficiently because its programs (figure la). The disk "opens up," and subroutines are coded in 68000 showing a window containing icons, Foundations of Macintosh Design assembly language (as opposed to each one of which corresponds to an The Macintosh computer is built on the Lisa, which uses less efficient item on the disk. To start using the three cornerstone ideas: second-gen- 68000 machine-language programs Mac Paint program, we select the eration Lisa technology, reliability that are compiled from high-level Mac Paint icon and choose the menu and low cost through simplicity, and Pascal source code). Third, the item "open," as shown in figure lb. maximum synergy between hard- Macintosh eliminates add-on periph- (We also could have opened Mac ware and software. Each of these eral cards and uses instead a high- Paint by double-clicking on the icon.) ideas contributes significantly to the speed serial bus that implements What follows is a brief example of uniqueness of the Macs design. what Apple calls "virtual slots." (I will how the Mac Paint program works. talk about this in greater detail When we open the program, we get Second-Generation below.) the screen of figure 1c. The large Lisa Technology The final difference is actually an blank area is a window onto the Without question, the strongest in- important limitation of the Macin- drawing area, the boxes on the left fluence on the Mac is that of the tosh: it allows only one major ap- are tools, the boxes on the bottom computer, which proved plication program to be active at a row are patterns, and the lines in the the viability of certain concepts in a time (the Mac BASIC and "desk ac-

Memory Hardware Options At a Glance 128K bytes of RAM. 64K bytes of ROM Second disk drive, keypad, Imagewriter Standard Configuration printer, security kit (for chaining com- Name Main unit with 128K bytes of RAM, 64K puter to table) Macintosh bytes of ROM, integral Sony 3½-inch Software Options disk drive, 9-inch video monitor, two Mac Paint (drawing program), Mac Write Manufacturer serial ports; external mechanical mouse: (a si mple word processor), Mac BASIC, Apple Computer external keyboard Mac Pascal, others (see text) 20525 Mariani Ave. Mass Storage Prices Cupertino, CA 95014 One Sony 3½-inch disk drive; 3½-inch Standard system, S1995-S2495 : Mac Paint (408) 996-1010 disk holds 400K bytes and is encased in and Mac Write (together), bundled at no a rigid plastic housing charge for the first 100 days, S195 (for the Dimensions Video Display two) thereafter; Macintosh Pascal, BASIC, 9.75 by 9.75 by 13.5 inches 9-inch monitor, noninterlaced 60.15-Hz Logo. Terminai, and Assembler/Debugger, Weight image, 512- by 342-pixel resolution S99 each; Mac Draw and Mac Project, Main unit. keyboard and mouse—22.7 Pointing Device $125 each; keypad, S99; second disk Ibs Mechanical mouse drive, $395: Imagewriter printer, $495 Power Requirements Keyboard 105-130 V AC, 60 Hz (U.S. model); Detached keyboard; 58 keys (59 in inter- 85-135 V AC, 50/60 Hz (international national version); autorepeat; two-key model) rollover

February 1984 BYTE Publications Inc. 31 Macintosh System Architecture by Burrell C. Smith Inside the Macintosh, hardware and pears in memory as a linear array of 10,944 a tightly coded routine generates 370 software work together to provide a system 16-bit words of data, with the most signifi- samples of sound data and places them into capable of supporting high-performance cant bit representing the pixel farthest left. the sound buffer just after a vertical retrace graphics, built-in peripherals, and commu- Each 512-pixel horizontal line consists of interrupt. The 68000 s 32-bit registers are nication channels to the outside world. 32 words of data, with bits shifted out at used to control pitch with 24 bits of preci- From the beginning of the Macintosh pro- 15.67 MHz (322.68 µs per 512-pixel line) sion, providing each of four possible voices ject, the product-design goals of small size, followed by 12 words of horizontal blank- with 16,777,216 possible frequencies. For light weight, and moderate end-user cost ing (taking 12.25 as). The last memory bus simpler sounds, a timer in the systems encouraged us to create a low-power, low cycle ofeach horizontal line is reserved for VIA provides a square wave of program- component-count design. The large num- sound DMA, where a byte of sound data mable pitch. All sounds pass through a ber of I/O devices that are built into each is fetched from the sound buffer and sent software-controlled volume adjustment unit, combined with our desire for high to the sound PWM (pulse-width modula- that creates approximately 20 decibels of performance, caused us to explore many tor) for conversion into an analog level. The total amplitude variation in eight discrete alternatives for each aspect of the hardware update rate of the sound channel is then steps. implementation. A cooperative spirit equal to the video horizontal rate, or The Macintosh disk controller is a single among the people working on the in- 22,254.55 Hz. In the vertical direction, LSI (large-scale integration) component dustrial design, analog electronics, digital 342 active scan lines are followed by a ver- referred to as the IWM ("integrated Woz electronics, and low-level software resulted tical retrace and enough inactive horizontal machine") chip. The device, a one-chip in- in the synthesis of detailed implementa- tegration of the disk controller originally tions that combined strengths from each The product-design designed by for the Apple group, providing an integrated design solu- It, handles data at 500 kilobits per second. tion for all aspects of the product. goals of small size, To control the disk drives motor speed, a The heart of the Macintosh digital elec- light weight, and pulse-width modulator located on the tronics is the MC68000 processor and its digital board allows the disk to move at one memory (both RAM and ROM). In the moderate end-user cost of 400 possible disk motor speeds; the Macintosh, the data-output lines from the encouraged us to PWM is driven from a table in memory in system RAM drive a data bus separate create a low-power, a fashion similar to that of the sound sys- from that used by the rest of the machine tem. By varying the motor speed, we (see figure 2). The RAM is triple-ported; low component-count created a more reliable disk drive that puts this means that the 68000, screen-display- design. significantly more data on the same disk. ing hardware, and sound-output hardware The Macintosh communications chip, have periodic access to the address and data lines to take up the same time as 28 hori- the Zilog 8530 SCC (serial communica- buses, so that the video, the sound, and zontal lines, providing a vertical retrace tions controller), provides synchronous and the current 68000 task appear to execute time of 1.258 ms. Although screen- asynchronous data transmission at up to concurrently. memory accesses may occur at any time, 230.4K bits per second using a self- ROM memory connects directly to the a vertical retrace interrupt is generated at clocking data format and up to 1 megabit system data bus and is used by only the the falling edge of the vertical sync pulse per second using an external clock. The 68000. Much of the systems time-critical to allow screen animation to occur com- Macintoshs two serial ports are identical; code, such as the low-level graphics primi- pletely synchronous to the video beam each provides single-ended or differential tives, operating-system routines, and user- movement. signaling and multidrop (party-line) interface routines, reside in ROM. Macin- Access to RAM is divided into syn- capability. tosh software calls this code through 68000 chronous time slots, with the 68000 and The 6522 VIA (versatile interface "line 1010 unimplemented" instructions, video circuits sharing alternate word ac- adapter) rounds out the I/O requirements which get one of approximately 480 ad- cesses during the live portion of the hori- of the machine by providing system timers, dresses from an address table stored in low zontal video-display line and the sound cir- support for the mouse and keyboard, and memory; this effectively allows the ROM cuits using the video time slot during the general-purpose I/O lines for selecting subroutines to function as extensions of the last memory bus cycle of the horizontal various system functions such as alternate 68000 instruction set. Since the ROM data line. Although the access to RAM is screen and sound buffers and for com- and address buses are used exclusively by divided three ways, the 68000s share is municating with the systems real-time the 68000, ROM is always accessed at the maximized by giving it access to unused clock and parameter memory. full processor speed of 7.83 MHz; conse- cycles during horizontal and vertical blank- quently, the ROM can perform as a read- ing. This way, 68000 access to RAM of the Apple only cache memory. averages to a speed of about 6 MHz. Burrell C. Smith is a member Macintosh design team. The 512- by 342-pixel video display ap- For high-performance sound generation,

3 2 February ½984 BYTE Publications Inc. Figures 1a-1h : Working with Mac Paint on the Macintosh computer. See text for details.

February ½984 BYTE Publications Inc 33 cessory programs are two exceptions that Ill cover later). This limitation is largely due to the Macs small mem- ory space and the overall design of the software, which assumes that the current program has access to all the machines memory. This is not as bad as it sounds; a single application can use multiple windows, and material can be cut and pasted from one docu- ment to another by storing the material to be pasted on a "clipboard" before loading in the second docu- ment (which replaces the first). Still, the absence of hardware slots and the inability to run two applications simultaneously are two important ways in which the Macintosh is fun- damentally different from the Lisa computer.

Reliability and Low Cost through Simplicity Although the Macintosh costs approximately one-third the price of a Lisa, the Mac has much more than one-third of the Lisas power. The idea of reliability through simplicity not only makes the Macintosh pos- sible at a relatively low price but also Photo 2: The Macintosh circuit boards. Photo 2a shows the analog board, while photo 2b produces a machine that has a reli- shows the digital hoard. These two boards plus the video display, 3½/2-inch disk drive, and housing make up the main unit; only the keyboard and mouse are needed to make a complete ability normally associated with Macintosh system. much simpler computers. One component of the Macs sim- plicity is its low chip count—it con- places in which hardware must be mutual give and take. For example, tains about 50 ICs (integrated cir- fine-tuned during assembly. In some the displayed on the Macs cuits), which decreases its physical cases, the designers eliminated the video display are square (not rec- size and price and increases its relia- need for adjustment through clever tangular, as in other computers); this bility. Mac reduces its chip count by circuit design, which also means greatly simplifies the software that combining the functions of many theres one less thing to go wrong draws squares and circles, scales text standard chips into eight program- with the computer once it is in the and graphics, and prints screen mable-logic arrays (PALs). owners hands. In other cases, Apple images. The Macintosh has only two circuit eliminated fine-tuning by requiring a boards, one that holds all its analog vendor of externally manufactured circuitry and one that holds all its subassemblies to tune the part before digital circuitry (see photos 2a and delivery; for example, the video-dis- Going for the 2b). By partitioning its functions and play tube and yoke are delivered pre- reducing the number of connectors adjusted, and the Sony 3 ½/2-inch disk World Market (by decreasing the number of boards drive is delivered tested and with Having learned from past experience, to be connected), the designers have several Apple-specified modifica- Apple designed the Macintosh so that it made the Mac both more reliable and tions. could easily be modified for all markets out- less expensive. They carried this side the United States. The following ex- philosophy farther by eliminating Maximum Synergy between amples show how pervasive nation- or lan- hardware slots; you add peripherals Hardware and Software guage-specific aspects of a computer design to a Mac through its two high-speed The Macintoshs hardware and are and how Apple has minimized the changes needed. serial ports. software were optimized for maxi- The Macintosh was designed to mum performance. This means that •Except for the word Apple" on the rear reduce (or, in the case of the digital the hardware and software evolved panel, the Macintosh has no English text board, eliminate) the number of over a period of time in a process of

34 February 1984 BYTE Publications Inc puters. The Mac is also pleasantly compact and light; an entire Mac sys- tem in an optional padded satchel weighs 25.6 pounds (less than many transportable computers) and can be carried onto an airplane. Figure 2 shows a block diagram of the ; for more details, see the "Macintosh System Architecture" text box. For now, lets look at the machines major subas- semblies: Processor: The Macintosh uses a 68000 processor running at 7.83 MHz. Video display: The Mac has a 9-inch monitor that displays a non- interlaced image at 60.15 Hz. The res- olution of the video image is 80 pixels per inch, so the overall screen is 512 by 342 pixels. ROM: The Mac uses two 256K-bit ROMs configured as 64K bytes of memory. The ROM (read-only memory) contains most of the Macs and a "toolbox" of optimized 68000 related routines (see the text box "The User Interface Toolbox" for more detail). The ROM is always accessed at full speed, 7.83 MHz. RAM: The Mac has 128K bytes of memory; at some (Apple says by the end of 1984), this will be ex- Hardware mouse and keyboard make for a total pandable to 512K bytes (by substi- The main unit of the Macintosh of 10 parts. The main unit takes up tuting 256K-bit dynamic RAM consists of eight parts: two circuit an amazingly small 10-inch by 10- (random-access read/write memory) boards, a cable to connect them, a inch area (it is 13 ½ inches high). chips for the 64K-bit chips currently chassis, a 3½-inch disk drive, True, the keyboard and mouse take being used). The screen display uses a video-display tube with yoke, and up more area than that, but the foot- 21,888 bytes and is drawn using this a plastic front bezel and rear housing print of the main unit is considerably memory and DMA (direct memory (see photos 3a and 3b). An external smaller than that of comparable com - access) circuitry. Apple has an un- Text continued on page 39

anywhere on the product or in the ROM. mats of time, dates, , and curren- the full Macintosh character set; the only Each plug is labeled with a picture that cy. With this method, the program itself advantage to having the keyboard for a cer- identifies its function. does not have to be changed and recompiled tain language is that the keyboard layout •The video-display rate of 60.15 Hz is gen- to make these changes. will be more appropriate for that language. erated internally instead of being derived •The keys on the keyboard are defined by from the line current. This allows the Mac the software, thus allowing Apple to With these innovations, the most time- to be used without modification in coun- change the keyboard easily to accommodate consuming part of modifying the Macin- tries that have 50-Hz line current. the special characters needed by some lan- tosh for another country is translating and •Macintosh software has been designed so guages. In addition, Apple has designed printing the documentation. Apple reports that all text , message layouts, the Mac so that two keyboards (differing that it will be shipping the Macintosh to and icons can be stored in a resource file, in only one key) can be used for all ver- several foreign countries "within several separate from the program itself. A de- sions of the product; Apple customizes a months of the Macs introduction." (Com- signer can use a resource-editor program keyboard for a given language by printing panies never seem to meet such deadlines, to change text (for example, to another lan- the necessary legends into the plastic keys. so expect foreign versions to be shipped be- guage), icons, message layout, and the for- In addition, any Mac keyboard can produce fore the end of 1984.)

February 1984 BYTE Publications Inc. 35 Figure 2: A block diagram of the Macintosh hardware. For more details, see the "Macintosh System Architecture" text box.

36 February 1984 BYTE Publications Inc. The User-Interface Toolbox

The toolbox (which occupies two-thirds The latter ability is needed to correctly ofthe high-speed 64K byte ROM inside the display window contents when one win- Macintosh) includes optimized 68000 dow overlaps others. The source code for machine-language routines that handle all Quickdraw is identical in both the Lisa and aspects of the Macintosh user interface the Macintosh. like windows, text, the mouse, pull- Event Manager: All system events (e.g., down menus, desk accessories, dialogue keypresses and mouse button presses) are boxes, and fonts. The figure below shows received and interpreted through this unit, the relative relationships among the dif- which mediates between the application ferent units (or packages of routines). Here program and the outside world. is a brief description of each unit, starting Toolbox Utilities: These routines han- with the lowest-level unit and working up: dle miscellaneous tasks that include string operations, fixed-point arithmetic, and bit- Resource Manager: These routines wise logical operations. coordinate the use of resources, which are Window Manager: Since all action on data structures such as text strings, the Macintosh display occurs within win- menus, and icon and font definitions. dows, this is a very important unit that These resources are kept separate from the is used a lot. The Window Manager allows actual code of an application, which means the application program to interact with that the resources of an application can be windows on a high level while it takes care modified without forcing a recompilation of the low-level details automatically. It (or modification) of the application pro- allows you to create different kinds ofboxes Dialog Manager: Dialogue boxes are gram. The Resource Manager is usually (document, dialogue, and alert boxes, for text boxes with several check boxes; usually, called by higher units like the menu and example), delete them, move them, change clicking the mouse button near a box selects font managers. their size, and make an inactive window it (and the action or condition associated Font Manager: This unit supports the active and vice versa. The Window with it) and unselects the previously use of various text fonts. It calls the Manager ensures that the computer auto- checked box. An alert box (as in figure h) resource when it needs to use a matically redraws the necessary screen alerts you to a potentially dangerous situa- font not already in memory, and it is usual- areas when some aspect of a window is tion and forces you to click on one of two ly called by the Quickdraw unit. changed. buttons, "Cancel" or "OK." The Dialog Quickdraw: Quickdraw is a graphics Control Manager: This unit controls Manager handles the display of and user package that is at the heart ofboth the Lisa the use of software buttons, check boxes, response to a dialogue or alert box. and Macintosh computers. , and dials, all of which can be called on to Desk Manager: This unit allows the its creator, worked for 3½ years on the show and alter the status of certain application program to use the desk ac- code, rewriting it many times and reduc- variables. cessories, which are resources that are ing it from a 160K-byte compiled Pascal Menu Manager: Given a two-dimen- called in from disk if they are not current- program to a 24K-byte package of highly sional matrix of menu items (each column ly in memory. optimized 68000 code. Atkinson, who was is a menu title followed by its selections), involved in the early design of the Lisas this unit controls the display and behavior user interface, designed and optimized of that matrix of pull-down menus. Applications can be written in Mac Quickdraw for the Lisa computer; he later Text Edit: These routines control ele- BASIC, Mac Pascal, or 68000 assembly joined the Macintosh design team. Quick- mentary text entry and editing. Text Edit language (usually one of the latter two). draw is very fastfor example, it can print is designed with lots of software "hooks" Both Mac Pascal and Mac BASIC are to the screen more than 7000 characters per so that you can modify its behavior but still designed so that their keywords directly call second. Two of its most interesting use it. An external unit called Core Edit, most of the toolbox routines. Most applica- capabilities are its ability to fill in any ar- which must be loaded into RAM, contains tions that use the routines are essentially bitrary shape with a pattern and its abil- more sophisticated entry and editing an endlessly repeating loop that for ity to "clip" an image to correspond to the routines; Core Edit can handle different an event, determines what kind of event boundaries of an arbitrary masking shape. fonts, sizes, and text styles. it is, and then processes the event.

February 1984 BYTE Publications Inc. 37 Macintosh System Software Overview interface software is designed to be flexible because we are still learning how to make by systems easier and more fun to use. The Macintosh is more than a power- tine, making each one as efficient as pos- Another reason for designing the software ful, inexpensive 68000-based desktop com- sible, knowing that our efforts would be this way is that trying to live for years puter. It comes with a built-in personality multiplied by the millions of units that we with what we thought was best at any provided by 64K bytes of handcrafted sys- will eventually ship. given time would doom us to eventual tem software contained in two ROM chips It is somewhat risky to put 64K bytes failure. High performance is extremely im- on its digital board. Besides performing of intricate system software in ROM on a portant in an interactive system; people traditional operating-system functions such disk-based system, but we did it because wont enjoy using a system unless it is very as memory and file management, the Mac- we wanted the machine to have a built-in responsive. intosh ROM includes the revolutionary standard user interface. By using our About one-third of the ROM is devoted Quickdraw package and a User-Interface ROM-based toolbox, a programmer saves to what we call the Macintosh Operating Toolbox to help programmers develop ap- development time and precious memory System, which contains many components plications that share a consistent, advanced space; this provides a positive incentive for found in more traditional systems. It in- user interface. doing it our way. Also, the price per bit cludes the low-level device drivers and in- The Macintosh ROM can be thought of of ROM is significantly less than that of terrupt handlers, an asynchronous I/O as an extension to the 68000 instruction RAM, and not having the operating system, a memory manager, a simple, fast set, augmenting its 56 basic instructions system load in from disk saves space on , a segment loader, and various with more than 480 new instructions every disk you have. Application programs utility routines. The I/O system supports designed for implementing fast mouse- never reference the ROM directly; instead, swappable, RAM-based device drivers as based applications. It is implemented en- they use compact "trap" instructions that well as its built-in serial, disk, and sound tirely in 68000 assembly-language code are interpreted by the system dispatcher. drivers. Most I/O and file-system calls can that has been handcrafted and optimized This allows us to intercept any routine to be made asynchronously, which allows an over a period of almost three years. We fix the program bugs that will inevitably application to overlap I/O tasks with other chose assembly language over a higher- arise. tasks. The memory manager minimizes the level language because it was very impor- The Macs system software design phi- fragmentation of available memory into tant for the system to be small and fast. losophy emphasizes simplicity, flexibility, small pieces by supporting relocatable ob- The Macintosh is intended to be a very and high performance. We chose the single- jects that are always accessed indirectly; high-volume product, and we could afford application-at-a-time philosophy to help the memory manager also provides an to lavish time and attention on every rou- keep things relatively simple. The user- automatic caching scheme by optionally

Photo 3: Inside the Macintosh computer. From the front (photo 3a), you can see the video display and the 3½-inch disk drive. From the rear (photo 3b), you can see the two main circuit boards (right and bottom), the rear of the video-display tube, the 3½-inch disk drive, and a row of connectors at the bottom of the unit. The connections go, from left to right, to the mouse, a second disk drive, two peripherals (these are two serial ports), and an external amplifier (for sound output).

38 February 1984 BYTE Publications Inc. purging objects as memory grows fuller. ponents are resources, windows, menus, desk accessories and are capable of cut- The file system ensures against loss of data controls, dialogues, and a text-editing ting and pasting data with each other as by maintaining tags on every block; these package. The window, menu, and control well as with the major application. We cur- allow the contents of a disk to be pieced back managers contain little information on how rently provide five desk accessories (calcu- together even if the directory is destroyed. individual windows, menus, or controls lator, clock, notepad, control panel for Another third of the ROM is occupied look or behave. Instead, this information default system parameters, and ). by Bill Atkinsons Quickdraw graphics is encapsulated in definition functions, By the spring of 1983, it became apparent package. Quickdraw, which is the corner- which are kept as resources and swapped that we would not be able to fit all the stone of Apples "Lisa technology," is into memory as necessary to implement routines that we had hoped to into our responsible for the Macs extremely fast messages sent by the various managers. 64K-byte ROM space. We designed a facil- user interaction. It draws practically every- This provides a very flexible structure ity to allow some system code (in the thing you see on the screen, including text capable of evolving as we learn how to im- system resource file) to be swapped in from (in a variety of typefaces and styles) and prove the user interface. disk to RAM when needed. We now use both filled and unfilled rectangles, lines, Another important goal of the Macin- five such RAM-based packages, including and ovals. It also is capable of representing tosh system software is to facilitate the a fully IEEE-standard floating-point arbitrary areas of the screen called regions passing of data between applications. A numeric package, a standard file dialogue in a very compact data structure. All scrap manager is provided to help ap- package, and an international string Quickdraw calls are clipped to the intersec- plications share data. It defines two data package that deals with various formats for tion of up to three regions, providing the types that every application is requested to date and time display. fundamental capability necessary for over- support (simple ASCII text and Quickdraw In summary, the 64K bytes of ROM- lapping windows. Quickdraw also is cap- pictures) and lets applications define their based provide Macintosh with a able of recording any sequence of procedure own custom types. It provides routines for unique personality and user interface, calls and saving them as a picture. Pic- transferring data in and out of the scrap. forming the foundation for the development tures provide an easy, powerful method for As stated above, Macintosh supports of communicating applications that share transferring graphics between applications. only one application running at any given a common user interface. The Macintosh The final third of the Macintosh ROM time. This restriction is mainly due to firmware is very fast and flexible, and it is occupied by the User-Interface Toolbox, limited available memory. By making a few will be exciting to see all the applications a collection of various managers and serv- simple calls to the desk manager, an ap- that develop from it in the years to come. ices intended to help a programmer develop plication may allow many useful mini- applications that conform to the Macintosh applications to run concurrently with Andy Hertzfeld is a member of the Apple Macintosh design team. standard user interface. Its principal com - itself. These small programs are called

Text continued from page .35: disclosed proprietary technique for When the video display is doing a screen display. The RAM is accessed phase-locking the 68000 to less ex- horizontal or vertical retrace, how- at 3.92 MHz during screen display pensive memory, which lowers the ever, the 68000 gets exclusive use of and at 7.83 MHz otherwise. The product cost without sacrificing the the RAM at its full speed, 7.83 MHz. average speed of the system is speed of memory access. This has a significant effect on the around 6 MHz. When the Mac is drawing a hori- average speed of RAM access. Out of One memory area of interest is the zontal line of the video display, the the 45 (microseconds) for each sound buffer. Along with associated 68000 and the video DMA circuitry horizontal display line, over 12 µs hardware, this buffer enables you to alternate (interleave) their accesses to (about 27 percent of the time) are oc- create four channels of arbitrary the RAM address and data lines. cupied by horizontal retrace. Of these sound while using no more than 50

Since these two can never access RAM 12 µsµs, about 0.5 µs is used to send percent of the 68000s computing simultaneously, the 68000 can never data to the sound and disk-speed cir- power. The 68000 performs look-up produce hashing or other glitches in cuitry, while the rest is available to operations every 44 µs on up to four the video display by accessing RAM the 68000. Furthermore, out of the 256-byte waveform tables; the result at the wrong time. Because of this 16.626 ms (milliseconds) used to draw of these lookups is placed in a interleaving, the 68000 accesses RAM each complete screen, 1.258 ms 370-byte sound buffer, from which at 3.92 MHz, half of the full 7.83 MHz (about 7.6 percent of the time) are the sound hardware fetches 1 byte rate, during the display of a hori- devoted to vertical retrace. Of this, every 44 µs to deliver to an 8-bit zontal line of the screen. This is done about 14 µs are used for sound and digital-to-analog circuit (DAC). An in- in the following way: the DMA cir- disk-speed control (representing the ternal VIA (versatile interface cuitry puts a word from RAM into control work done at the end of the adapter) can also be used to generate the video shift register; while the equivalent of 28 unused horizontal a single square-wave tone while register is sending out those 16 bits lines of video), leaving more than using an insignificant part of the serially to the screen, the 68000 uses 1.244 ms for the 68000 to access RAM 68000 s computing power. RAM for its own purposes; then the at full speed. Mass storage: The Macintosh uses cycle begins again with the DMA To summarize, the ROM is always a custom version of the Sony 3½-inch circuitry. accessed at 7.83 MHz, regardless of disk and drive (see photo 4). The

February 1984 BYTE Publications inc. 39 The Macintosh Memory Map

The Macintosh memory map contains The VIA (versatile interface adapter) addition, they allow the SCC to detect RAM, ROM, and I/O devices that com- locations are used by the Macintoshs 6522 mouse (in conjunction with the municate with the 68000 through specified VIA. This chip gives the Macintosh VIA) and adjust the phase of the Macin- memory locations. When the Macintosh is parallel input, output, and interrupt lines, tosh timing signals. turned on (i.e., at boot-up), the 64K-byte shift registers, mouse information, and Most programmers will not need in- ROM maps into the first page of memory clocks. timate knowledge of the Macintosh and is used to get the system started. After The IWM locations are used by the memory map. The 64K-byte ROM contains boot-up, the positions of RAM and ROM Macintoshs IWM (integrated Woz ma- sophisticated routines that take care of low- are changed so that the 128K-byte block of chine), which controls all access to the in- level processes like I/O, memory manage- RAM occupies the first two of ternal 3½-inch disk drive and the optional ment, video display, and similar tasks. Ap- memory (see figure below). external one. ple encourages the use of these routines; The Phase Read area of memory is used The SCC Read and SCC Write locations they mean less development time, con- to determine whether the computers are used for several purposes. They allow formity to the standard Macintosh user in- timing signals are correctly in phase with the SCC (serial communications controller) terface, faster programs (ROM always runs each other; this is usually done by ROM chip to handle two serial ports at rates be- at full speed), and more memory space for routines at boot-up. tween 30 and 230,400 bits per second. In programs and disks.

40 February 1984 C BYTE Publications I nc In addition to the change to 80 tpi, Apple contracted Sony to modify the drive in several other ways. Two changes allow the Sony drive to mimic the behavior of the Lisa "twiggy" drives (which were original- ly chosen for use in the Mac): disk ejection under software control and variable disk-rotation speed. The first change allows the Mac to ensure that a disk is correctly updated before it is surrendered to the user (that is, you can t take a disk out of the drive until the Mac software permits it). The second change enables the Mac to record onto the disk at a constant linear density (which means you can put more data on the outermost tracks), as opposed to the constant radial density approach most com- Photo 4: The Sony 3½-inch disk is encased in a rigid plastic housing, and the oval window through which the magnetic medium is accessed is protected by a metal shutter that slides puters use (which puts the same out of the way when the disk is inserted in the drive. These factors help protect the disk from amount of data on each track regard- casual use. less of position). The Macintosh s drive rotates drive can store 400K bytes on a 70 tracks of data at 135 tpi (tracks per under software control between 390 single-sided 3 ½/2-inch disk; the Mac is inch) onto each disk. At Apples urg- and 600 rpm (revolutions per minute) designed to be able to use double- ing, Sony now makes the drive in and transfers data at the rate of sided drives to get 800K bytes per another model that has 80 tracks of 489.6K bits per second (bits as re- disk, an option that Apple may pur- data at 135 tpi. As a comparison, the corded on the disk, not decoded data sue at a later date. The standard Sony Hewlett-Packard HP 150 uses the bits). Most computers use a disk- 3½-inch disk (used to date by Hew- 70-track version and conventional controller chip instead of the pro- lett-Packard and other vendors) puts sectoring to get 270K bytes per single- cessor to control the drive. The Mac sided disk. (like the Apple II) uses its processor to directly control the drive. Because the Macintosh can control more disk- related parameters than the Apple II Sharing Data among Programs (the variable motor speed, for exam- ple), Macintosh owners will be Macintosh programs, if they are de- makes up the actual contents of the data signed in with Apple guide- item. treated to an even greater wealth of lines, will be able to trade data among Programs are free to implement their copy-protection schemes than Apple themselves without one program having own data types. Apple has defined two II owners enjoy. Also, the Macintosh to know anything about the nature of the text and Quickdraw picturesand en- drive uses modified group code record- others. This is done through use of a courages every program to be able to read ing to encode data onto the disk. This shared memory area called the clipboard both and write at least one of these data technique, invented by Steve Woz- and the standardization of the data that can types. Text is a simple ASCII string of niak for use with the Apple II, en- be stored in it. characters without any information on the codes 6 bits of data into an eight- The clipboard is a relocatable piece of size, font, or position of the text. Quick- transition group that is recorded onto memory that is not erased when a new pro- draw pictures are defined as a sequence of the disk surface. gram replaces an older one. It is used as commands that can be understood by the Keyboard: The keyboard has 58 follows: the first program copies data into Quickdraw routines. A Quickdraw picture the clipboard, the second program replaces can contain displayable text (which does keys; the left Shift key is split on the the first with its own code and data, and include information on text size, font, and international version of the Macin- the data in the clipboard is added to the position on the screen), a sequence of tosh, giving it a total of 59 keys. The data now in memory. The clipboard can elementary graphics commands that will keyboard includes Return, Caps contain a variable number of data items, recreate the image, or the image described Lock, and Shift keys in their usual though every item must be of a different as a stream of bits. These two data types places, two Option keys, and a type. Each data item consists of a four- provide a guaranteed means of communica- cloverleaf (see photo character data-type identifier, a 32-bit tion among Macintosh programs. 5). Combinations of the Shift, Caps length (in bytes), and a stream of bytes that Lock, and Option keys give each key up to six meanings; the command key

42 February BYTE Publications Inc. acts as a modifier and is often used scheme will be used to connect most the peripherals connected. with a letter key as the keyboard sub- peripherals, which need only a low The virtual-slot scheme is both stitute for a mouse-selected menu to medium data-transfer rate, to the practical and elegant; it offers a item. The keyboard contains an 8021 Macintosh in a passive daisy-chained simple, standard way to connect un- and is connected to line. This scheme implements what specified future peripherals. The the main box by a four-wire bidirec- the Macs designers call "virtual 230.4K bit-per-second data-transfer tional serial connection. The connec- slots." rate is high enough to meet the needs tions on both ends use the same kind Virtual slots have several advan- of most peripherals—printers, of square modular plug found in tages over conventional hardware modems, plotters, synthe- most telephones. peripheral slots. They reduce the sizers, and so on. However, one class Mouse: The Mac s one-button potential problems inherent in any of add-on card will not work using mechanical mouse, about the size of added mechanical connection (a this scheme: processor cards like the a pack of cigarettes, is essentially the serial interface connector has fewer Softcard, which allow a same as the Lisas; it differs only in pins than a typical interface board). computer to run another processors the shape of the plastic housing. The They reduce RFI (radio-frequency in- software. Such cards require full ac- mouse is used to position the cursor terference) by keeping the main box cess to the data and address lines and on the screen; when you slide the leakproof and allowing easy, inex- will not work via a serial "virtual mouse over a horizontal surface, the pensive shielding of the serial line. slot." As a result, despite some cursor moves in the same direction By deciding that peripherals will rumors to the contrary, the Macin- on the screen. supply their own power, the Macin- tosh will never use IBM PC- or MS- Serial bus: The Macintoshs serial tosh designers were able to stream- DOS-based software. bus is very important because it is the line the power supply of the main Power supply: Apple designed two way that most future peripherals (ex- box without worrying about the power supplies for the Macintosh. cept the second 3/2-inch disk drive power needs of unspecified future The first one uses a 60-watt switch- and the keypad) will connect to the peripherals. Finally, virtual slots ing power supply similar to one used computer. The bus can run in two eliminate the need of peripheral in the Apple II family; it can operate modes: with an external clock, it can cards to insert themselves some- on 85 to 135 V AC at either 50 or 60 transfer data at up to 1 megabit per where in the computers memory Hz. For technical reasons, use of this second; with internal clocking (which map; the unchanging memory map power supply would have delayed embeds clock bits in the data stream creates a known, unchanging system the introduction of the machine, so itself), it can transfer data at up to architecture that all software design- Apple designed and produced a 230.4K bits per second. The latter ers can be assured of, regardless of simpler nonswitching power supply

Photo 5: The Macintosh keyboard.

February 1984 BYTE Publications Inc. 4 3 (105 to 130 V AC, 60 Hz) for initial use at 7.83 MHz. The ROM contains most that perform the details of such com- in the first U.S. models of the Macin- of the Mac operating system and a set plicated operations with minimum tosh. The first switching power sup- of optimized 68000 routines called programming on the application de- ply will be used later in the year for the Macintosh User-Interface Tool- signers part. For example, the the international model and possibly box. The operating-system software window-management routines take for the U.S. model. interacts at the lowest level with the care of correctly redrawing the dis- The supply was designed to drive hardware; it includes such things as play when a window is moved or two twiggy disks; when the design device drivers and memory- and file- changed. For more details, see the was changed to include two 3½-inch management routines. The toolbox text box "The User-Interface Toolbox." disks instead, the supply had a contains various routines that let you The designers intend for you to ac- sizable margin of unused power. manipulate windows, text, the cess all ROM routines indirectly via mouse, pull-down menus, desk ac- the 68000 "line 1010 unimplemented" System Software cessories, dialogue boxes, fonts, and instructions, which receive their ad- As stated before, the Macintosh other aspects of the Mac user inter- dresses from a table in RAM; this contains 64K bytes of ROM accessed face. These are high-level routines table can be changed to point to other routines, thereby allowing future ver- sions of Mac software to patch the in- evitable bugs that will be found in the Mac ROM. Because the application drives the ROM routines (instead of the other way around), the Macin- tosh is an "open" system whose behavior is completely determined by the contents of the disk inserted into it—that is, software designers can use the ROM routines to create a "stan- dard" Macintosh application, or they can write their own code to create an application that behaves the way they want it to. Although the designers of the Macintosh have a general philosophy of allowing only one application pro- gram to be open at a time, they have included in the main menu a collec- tion of short, useful programs that can run without forcing you to end your current program. Apple calls these programs desk accessories. Many of the accessories are simply con- veniences—the clock accessory, for example, shows you the current date and time—but a very powerful ac- cessory is called the scrapbook. Or- dinarily, you can cut and paste data from one document to another by cutting the data into the clipboard, loading in the new document, and pasting in the data; this process would be tedious if you had several items of the same type to cut and paste. The scrapbook is a sequence of data items—text or graphics—that can be stored or recalled together, thus minimizing the number of document changes and allowing you to recall often-used data items easily. The scrapbook is actually imple- mented as a disk file; as a result, it

44 February 1984 C BYTE Publications Inc. Circle 327 on inquiry card. tends to be rather large. sees the magnetic medium as being the file number, sequence-within-file System software reacts to all pe- more likely to fail than the elec- number, and date/time stamp for the ripherals on an asynchronous basis— tronics. The Sony 3½-inch disk is bet- data in the rest of that block; this can peripherals compete for the attention ter suited to the consumer environ- be used in many situations to recover of the 68000 by sending it interrupts, ment. The drive can hold an accept- most or all of the data on the disk. which the 68000 services according to able amount of storage per disk, and the level of the interrupt. This keeps the small disk, with its rigid shell and Applications and Languages the 68000 from being tied exclusively normally closed access window, is Neither application software nor a to a peripheral—for example, to the less likely to suffer from bad handling language is included in the basic 3½-inch disk drive waiting to get up than a conventional 51/4-inch floppy Macintosh package. However, a two- to its full speed—when it could be disk. In addition, the magnetic program set will be available for $195; doing something more useful. The medium is connected to a steel hub both programs require the recently Macs designers have managed to do that the drive mates with and rotates. introduced Imagewriter printer to this even with high-speed periph- 51/4-inch This is an improvement over print things out. The first program is erals that usually require the full at- floppy-disk drives, which clamp the Mac Paint, the drawing program we tention of a processor. For example, Mylar edge of the center hole. The looked at earlier. Created in house at disk and serial-port routines have 3/2-inch disk hub is needed to get ac- Apple, Mac Paint is limited to draw- been dovetailed to permit the use of curate enough disk-head placement ings that will fit on one 81/2- by both peripherals at the same time. to make a data density of 135 tracks 11-inch page. Mac Paint is unlike the per inch possible. Lisa drawing program (Lisa Draw) in Disk Reliability The data on the disk is encoded in that it manipulates the drawing on a Reliability was one of the main a way that enables the Macintosh to bit-by-bit level (a Lisa Draw drawing reasons that Apple decided to use recover from some disk medium or is stored as a collection of elementary the 3/2-inch Sony disk drive instead disk file errors. The file directory is objects—circles, text, boxes, etc.). This of the 5 ½/4-inch twiggy drive. (A pro- duplicated in a normal disk file representation makes some things, jected shortage of twiggy drives was (which can be used if, for some such as arbitrary erasures, easier on another reason.) Apple is expecting reason, the directory is damaged). the Mac and other things, such as de- the Macintosh to be the first real Also, each block of data on the disk leting a single object within the draw- consumer-oriented computer, and it includes a 12-byte identifier that gives ing, harder.

46 February 1984 C BYTE Publications lnc - Figure 3: The Mac Write word-processing program.

The second program in the set is on a line-by-line basis. Both have terminals—available first quarter, Mac Write (figure 3), which was graphics and mouse commands that $99). Also planned are Mac Draw (an created out of house for Apple and call on the toolbox routines in ROM, object-oriented drawing program) can handle documents up to 10 and both use floating-point arith- and Mac Project (a scheduling and single-spaced or 20 double-spaced metic routines (in RAM) that meet project-management program). pages. Like Lisa Write, Mac Write can the IEEE 754 floating-point standard. These are both Macintosh versions of handle multiple fonts and sizes as Mac Pascal, which was created out two Lisa application programs; each well as variations achieved by adding of house, is interesting in that it is the costs $125 and will be available in the any combination of five modifiers— only Pascal I know of that can be ex- third quarter of 1984. underline, bold, italic, outline, and ecuted interactively. Another nice shadow. feature is its syntax checker, an item Third-Party Software Apple Macintosh Pascal, Assem- that can be called from its "Run" Apple has not spent all its energy bler/Debugger, BASIC, and Logo will menu. This menu item is often trying to write all the software that cost $99 each; the first two will be handy for finding those petty syntax the Macintosh needs. Instead, it has available during the second quarter errors to which Pascal code is prone. created two exemplary Macintosh of 1984, and the other two will follow Mac BASIC was created in house packages and gone to third-party in the third quarter. The Logo is from by Donn Denman, who worked on software developers to get them to LCSI, which developed Apple II Apple III Business BASIC. An inter- create the bulk of available Macintosh Logo. Both the BASIC and Pascal active, multitasking BASIC, it can ex- software. Apple estimates that by the compile on a line-by-line basis into an ecute multiple copies of the same time you read this, the Mac will be intermediate pseudocode, which program or multiple programs simul- in the hands of more than 100 soft- gives them the speed of compiled taneously; each program and each ware vendors. languages while retaining the interac- running task has its own window. At the time this was written, some tive nature of interpreted languages. Other Apple programs announced software developers had made com- Both languages use separate win- for delivery in 1984 include Mac Ter- mitments to market Macintosh soft- dows for program source code and minal (which emulates the DEC ware. Microsoft and output, and both can be debugged VT-52 and VT-100 and Teletype ASR33 BASIC will be available at the Macs

48 February 1984 C BYTE Publications lnc. 50 February 1984 C BYTE Publications lnc the inside face of the plastic rear housing. By the Way. . . Dont try to look for them, though; the Mac is not supposed to be opened except •No, we didnt misspell the name. "McIn- angelo." People at Apple decided that the by repair people. tosh" is the apple, but "Macintosh" is the names were too cute to use; they were •The Macintosh is not going to be strictly Apple computer. The products original right. a "serious" computer. Some of the software was misspelled by its first users, •Apple is one of those exceptional com- engineers at Apple are very excited about and Apple decided to stay with that panies that gives its employees credit in- the great games that could take advantage spelling. stead of commanding them to work in ano- of the Macs computing power and high- •The Mac Write program was originally nymity behind the corporate name. The resolution graphics. I saw an incredible named "Macauthor," and the Mac Draw names of the hundred or so employees who game that has Alice (of Wonderland fame) program was originally named "Mackel - worked on the Macintosh are molded into dodging animated chess pieces in 3D.

introduction; Microsoft File, Chart, through the keypad, and into the Service and Word will be available by mid- keyboard itself. Another product, an- The Macintosh has no user-service- February. Lotus is working on con- nounced but not scheduled, is exter- able parts. Unlike the Lisa computer, verting its popular 1-2-3 nal hardware that will give the Mac the Mac is not meant to be opened by program. Software Publishing Cor- IBM 3270 emulation capability. the user; you are expected to return poration will have its PFS File and your Mac to an authorized Apple ser- PFS Report programs available some- Documentation and Training vice center for repair. The Mac comes time in April. In its ads, Apple is stressing the with Apples standard 90-day parts- necessity of going to a Macintosh and-labor warranty. You can also buy Optional Hardware dealer and trying the computer out. a one-year maintenance contract. Ac- The Macintosh uses Apples new Once you have bought it, though, cording to Apple, other service plans $495 dot-matrix Imagewriter printer, you will probably be learning how to will be available, including options the only printer that is supported by use the Mac on your own. Apple will for large-volume purchasers of the the current print driver within the help you in this process by providing Macintosh. Macintosh. To get its level of graphics you with a cassette/disk combination. and text quality (see listings la You boot up the 3½-inch disk tutorial Caveats through lc), the Imagewriter usually and listen to the interactive lesson I wrote this article after two days of stays in a graphics mode that prints provided on the cassette. (Of course, meetings with various members of a single column of dots for every byte you have to have a cassette player.) the Macintosh staff, studying pre- sent to it by the Mac. However, the Although I have not seen the cas- liminary Mac documentation, mak- Imagewriter can print text in three sette/disk tutorial program, I think it ing numerous phone calls to Apple, modes: a high-resolution mode will work well; text-only tutorial pro- and working for several days (over a (listing lb), a medium-resolution grams are fine, but many buyers of period of weeks) with a Macintosh mode (listing 1c), and a draft mode the Mac will benefit from the warmth computer. I used several final-draft that uses the printers built-in char- of a human voice teaching them. versions of Mac Write and Mac Paint, acter set for quick text-only printing. I saw final-draft copies of only two though I occasionally found oper- (I found I prefer the medium- over Macintosh product documents. Ex- ating-system features that "crashed" the high-resolution text.) Although plore Mac Paint is a booklet (about 25 the system or werent yet imple- the Imagewriter could hardly be pages) that teaches you about Mac mented. Apple was still making called fast, it is not unacceptably Paint by showing you what it does. minor changes to both software and slow, and it is considerably faster It is very easy to read because it has pricing when this was written. than the Apple Dot-Matrix Printer more pictures in it than text. Mac running under the Lisa computers Write is much longer and looks more Commentary parallel port. like conventional documentation. It There is a lot to like about the Two other pieces of hardware are is sensibly divided into three sec- Macintosh; it is a superb example of an external disk drive (at $395, tions: "Learning Mac Write" (a do-by- what American technology can do available during the first quarter) and example tutorial that shows you most when given the chance. The simple, a ($99, at introduc- of the features of the program), compact, economical design, the vir- tion). The external disk driver con- "Using Mac Write" (a "cookbook" tual slots, and the enhanced perform- nects to the main unit via a dedicated showing you how to accomplish ance of 128K bytes of memory be- "second disk" connector in back. many common tasks), and "Refer- cause of the 64K-byte ROM code are When the keypad is connected, the ence." All in all, the documentation all important innovations done well. keyboard line runs from the Mac, should be quite good. Im glad that Apple decided to go

February 1984 1 BYTE Publications Inc. 51 with a Sony 3 ½ -inch disk (as com- pared to the Lisa 1, which needs spe- cial, expensive, hard-to-get twiggy floppy disks). However, Im disap- pointed that both Apple and Hew- lett-Packard have used nonstandard formats that are incompatible with each other. It would have been nice to start the widespread use of the Sony microfloppy with a standard disk format, but the incentive to sacrifice standardization for perform- ance is one of the drawbacks of a competitive industry. I also feel strongly that the basic Macintosh package should include two disk drives. With a one-drive sys- tem, it will take at least eight disk swaps to back up a 3½-inch disk. How many people (especially nov- ices) will go to this trouble, and how many will suffer when they dont? (I am not alone in feeling this way; the first thing two BYTE editors said when they first saw the Macintosh was, "Only one disk drive? Youve got to be kidding!" After numerous disk swaps when trying to load Mac Paint from one disk and a drawing from another, I am convinced that most users will eventually buy the second disk drive.) At the time this was written, Apple was committed to a totally unbun- dled pricing of the Macintosh—that is, the basic Macintosh package (at $1995 to $2495) includes the main unit, the keyboard, the mouse, necessary cables, a tutorial disk, and a disk containing the operating sys- tem. Everything else—Mac Write, Mac Print, all languages, the Image- writer printer, and the second disk drive—is priced separately. Since manufacturers want to claim the lowest possible price for their prod- ucts, unbundling is common (IBM, for example, introduced the IBM PC with a low-end model, 16K bytes of memory, and a cassette port for $1265). True, the low-end Macintosh is far more complete than most manufacturers low-end products, but Apple has taken unbundling far- ther than any other microcomputer vendor—no one has sold a computer without BASIC (or some other lan- guage) in years. A usable Macintosh system with

52 February 1984 BYTE Publications lnc. Mac Write, Mac Draw, a program- vendors of some other 68000-based because it was the first commercial ming language, and the Imagewriter microcomputers, but I hate to see product to use the mouse-window- printer costs from $2589 to $3189; a Apple hyping a machine that easily . The Macin- second disk drive will add another stands on its own merits. tosh is equally important because it $395. Apple would be wise to make makes that same environment very this package available at a dis- Conclusions affordable. It is also important counted package price, just as it now Exactly a year ago, in a product because it is a second-generation does for the Apple Ile. Apple con- description of the Apple Lisa com- design that, in several areas, im- tends that the Macintosh will be- puter, I said, "Technology, while ex- proves on the original. come a home machine because office pensive to create, is much cheaper to The Macintosh will have three im- users will take it home a few times portant effects. First, like the Lisa, it and like it enough to buy themselves The Macintosh is still will be imitated but not copied. In the one for their personal use. However, too expensive to year since the Lisa was announced, the Mac is still too expensive to penetrate the home dozens of hardware and software penetrate the home market signi- companies have announced products ficantly; that will be left to less market significantly; that duplicate part of the Lisa user expensive machines, such as the that will be left to less environment—the mouse, the win- , the IBM PCjr, the expensive machines. dows, the integrated software. Some, Apple II family, and the Coleco like Microsofts mouse-based series of Adam. distribute. Apple knows this machine packages and Visicorps , have Finally, I have to point out that, is expensive and is also not unaware tried to mimic that environment on although Apples advertisements call that most people would be incredibly a smaller, less expensive machine the Macintosh a 32-bit system, its interested in a similar but less expen- (the IBM PC) with only partial MC68000 processor is generally re- sive machine. Well see what hap- success. garded as a 16-bit processor (the pens" In a similar way, companies will be limiting factor is its inability to deal Now we have seen what has hap- out to imitate the Macintosh, but with multiplicands greater than 16 pened, and it is rather impressive. their attempts will be less successful. bits). This is no different from the The Lisa computer was important Those companies that try to imitate

Circle 160 on inquiry card. February 198 4 BYTE Publications Inc. 53 the Mac on other machines will have new system that would be compar- with the Macintosh in size and price; trouble matching its price/perform- ably priced. This will probably not be Apple is confident that a number of ance combination. So far, attempts to attempted; only a few corporations its components and manufacturing imitate the Lisa by enhancing an ex- have the ability to duplicate Apples techniques will be difficult to copy. isting computer (usually an IBM PC) design and manufacturing effort, and Even though Apple has suffered have been given the benefit of the still fewer will make such a large from -copy Apple II machines, doubt because they are less expensive financial commitment. (Apple is the it does not expect to have the same than the Lisa; attempts to imitate the only American company that does thing happen with the Macintosh. Macintosh will now have a harder not live under the tyranny of Second, the Macintosh will secure time because the Mac with software is quarters profits; if any company tries the place of the Sony 3½-inch disk as about as cheap as the host hardware to duplicate Apples effort, it will the magnetic medium of choice for alone. probably be a Japanese one.) Those the next generation of personal com- The only other way to match the that try will find it hard to create puters. I was disappointed when I Mac would be to design an entirely similar technology that competes first saw that the Mac used the 3½-inch disk—"Another disk format to contend with; I thought, "and you cant use disks from the Lisa." (You will be able to use Mac disks with the new Lisa 2; see Apple Announces the Lisa 2," on page 84.) Once I had heard Apples line of reasoning, though, I had to agree with its choice. Hewlett-Packards HP 150 is the only other major computer to use the Sony 3½-inch disk to date; Apples use of it will tip the scales in Sonys favor, and other manufacturers will follow. Third, the Macintosh will increase Apples reputation in the market; in fact, to some people Apple will be as synonymous with the phrase "per- sonal computer" as IBM is synony- mous with "computer." The Mac will compete with IBMs PC, not its cheaper sibling, the IBM PCjr. Many business users will stay with the "safer" IBM PC. However, people new to computing and those who are maverick enough to see the value and promise of the Mac will favor it. The Mac will delay IBMs domination of the market. Overall, the Macintosh is a very im- portant machine that, in my opinion, replaces the Lisa as the most impor- tant development in computers in the last five years. The Macintosh brings us one step closer to the ideal of com- puter as appliance. Were not there yet—at least, not until the next set of improvements (which, in this in- dustry, we may see fairly soon). Who knows who the next innovator will be?

Gregg Williams is a senior editor at BYTE. He can be reached at POB 372, Hancock, NH 03449.

54 February 1984 BYTE Publications Inc.