Apple II family
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The Apple II (sometimes written as Apple ][ or Apple //) was the first microcomputer manufactured by Apple Computer. Its direct ancestor was the Apple I, a circuit board computer for hobbyists that was never produced in quantity but which pioneered many of the features that made the Apple II a success. Introduced at the West Coast Computer Faire in 1977, the Apple II was one of the very first and most successful personal computers. A number of different models were sold, and the most popular model was manufactured, with relatively minor changes, into the 1990s. By the end of its production, 2 million Apple IIs were produced.
Unlike any other machine before it, the Apple II looked more like an appliance than a piece of electronic test equipment. This was a computer that would not seem out of place in the home, on a manager's desk, or in a classroom. The lid popped easily off the beige plastic case, allowing access to the entire motherboard and inviting users to look inside and tinker with the computer's eight expansion slots and its bounty of empty RAM sockets, which could hold up to 48 kilobytes of memory.
Also unique for its time were the machine's color and high-resolution graphics modes (which could be used on an ordinary television), its sound capabilities, and its built-in BASIC programming language. Compared to earlier machines, these features were well-documented and easy to learn. The Apple II thus marked the beginning of the personal computer revolution: it was a machine for the masses, not just hobbyists, scientists, and engineers. The Apple II's influence was widespread; most of the machines that followed imitated many aspects of the successful machine.
Throughout the 1980s and much of the 1990s, the Apple II was the de facto standard computer in American K-12 schools and even some colleges and universities. Some of these machines are still operational in classrooms today. The Apple II was popular with business users as well as with families and schools, particularly after the release of the first-ever computer spreadsheet, VisiCalc, which initially ran only on the Apple II.
See the computing timeline for dates of Apple II family model releases – the 1977 Apple II and its younger siblings, the II Plus, IIe, IIc, IIc Plus and IIGS.
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History
The original Apple II
The first Apple II computers went on sale on June 5, 1977 with a MOS Technology 6502 microprocessor running at 1 MHz, 4 KB of RAM (expandable to 48 KB), an audio cassette interface for loading programs and storing data, and the Integer BASIC programming language built into the ROMs. The video controller displayed 24 lines by 40 columns of upper-case-only text on the screen, with NTSC composite video output suitable for display on a monitor, or on a TV set by way of an RF modulator. The original retail price of the computer was $1298 with 4KB of RAM and $2638 with 48KB of RAM, the maximum amount of memory supported on the original motherboard.
To reflect the machine's then-unique color graphics capability, the Apple logo on the computer's case was made up of rainbow stripes, and these remained a part of the logo until early 2000.
Later, an external 5¼-inch floppy disk drive, the Disk II, attached via a controller card that plugged into one of the computer's expansion slots (usually slot 6), gave users much more convenient data storage and retrieval. The Disk II interface, created by Steve Wozniak ("Woz"), is still regarded as an engineering masterpiece. Where other controllers had dozens of chips for synchronizing data I/O with disk rotation, seeking the head to the appropriate track, and encoding the data into magnetic pulses, Woz's controller card had few chips; instead, the Apple DOS used software to perform these functions. The Group Code Recording used by the controller was simpler and easier to implement in software than the more common MFM. According to legend, Woz laid out the circuit board several times as he realized that moving one more function to software would allow him to remove yet another chip. In the end, the low chip count of the controller contributed to making Apple's Disk II the first affordable floppy drive system for personal computers. As a side effect, Woz's scheme also made it easy for proprietary software developers to copy-protect the media on which their software shipped by changing the low-level sector format or stepping the drive's head between the tracks; naturally, other companies eventually sold software to foil such protection.
The approach taken in the Disk II controller was typical of Woz's design sensibility. The Apple II is full of clever engineering tricks to save hardware and reduce costs. For example, by interleaving the video generation circuitry's memory access with the CPU's, a feature unique to the 6502, Woz eliminated the need for a separate refresh circuit for the DRAM chips. Rather than using a complex analog-to-digital circuit to read the outputs of the game controller, Woz used a simple timer circuit whose period was proportional to the resistance of the game controller, then used a software loop to measure the timer. The text and graphics screens had a frankly Byzantine arrangement (the scanlines were not stored in sequential areas of memory) which reputedly was due to Woz's realization that doing it that way would save a chip; it was less expensive to have software calculate or look up the address of the needed scanline than to include the extra hardware. Similarly, in the high-resolution graphics mode, color was determined by pixel position and thus could be implemented in software, saving Woz the chips needed to convert bitplanes to colors.
The epitome of the Apple II design philosophy was the Apple II sound circuitry. Rather than having a dedicated sound-synthesis chip, the Apple II had a toggle circuit that could only emit a click through a built-in speaker; all other sounds (including two, three, and eventually four-voice music and playback of audio samples and speech synthesis) were generated entirely by clever software that clicked the speaker at just the right times. Not for nearly a decade would an Apple II be released with a dedicated sound chip. Similar techniques were used for cassette storage; the cassette output worked the same as the speaker, and the input was a simple zero-crossing detector that served as a very crude (1-bit) audio digitizer. Routines in the ROM were used to encode and decode data in frequency shift keying for the cassette.
The Apple II's brilliant quirks served as a gauntlet that drew scores of equally quirky and brilliant programmers to the platform, and these became the Apple II's lifeblood.
Wozniak's open design and the Apple II's multiple expansion slots permitted a wide variety of third-party devices to expand the capabilities of the machine. Apple II peripheral cards such as Serial controllers, improved display controllers, memory boards, hard disks, and networking components were available for this system in its day. There were also emulator cards, such as the Z80 card which permitted the Apple to switch to the Z80 processor and run a multitude of programs developed under the CP/M operating system, including the dBase II database and the WordStar word processor. There was also a third-party 6809 card with which one could run OS-9 Level One. The Mockingboard sound card greatly improved the audio capabilities of the Apple with simple music synthesis and text to speech. Eventually Apple II accelerator cards were created to double or quadruple the computer's speed.
The family grows
Apple II Plus
The Apple II was eventually superseded by the Apple II Plus, which included the Applesoft BASIC programming language in ROM. This Microsoft-authored dialect of BASIC, which was previously available as an upgrade, supported floating-point arithmetic (though it ran at a noticably slower speed than Steve Wozniak's Integer BASIC) and became the standard BASIC dialect on the Apple.
The Apple II Plus had a total of 48 kilobytes of RAM, expandable to 64 KB by means of the language card, an expansion card that could be installed in the computer's slot 0. The Apple's 6502 microprocessor could support a maximum of 64 KB of memory, and a machine with 48 KB RAM reached this limit because of the additional 16 KB of read-only memory and I/O addresses. For this reason, the extra RAM in the language card was bank-switched over the machine's built-in ROM, allowing code loaded into the additional memory to be used as if it actually were ROM. Users could thus load Integer BASIC into the language card from disk and switch between the Integer and Applesoft dialects of BASIC with DOS 3.3's INT and FP commands just as if they had the BASIC ROM expansion card. The language card was also required to use the UCSD Pascal and FORTRAN 77 compilers, which were released by Apple at about the same time. These ran under a non-DOS operating system called the UCSD P-System, which had its own disk format and included a "virtual machine" that allowed it to run on many different types of hardware.
Like the Apple II, the Apple II Plus had no lowercase functionality. All letter keys on the keyboard would type uppercase letters, and there were no lowercase letters in the text-mode font stored in the computer's ROM. (Note the lack of a caps lock key on the keyboard.) To display lowercase letters, some applications would run in the slower hi-res graphics mode and use a custom font, rather than running in the fast text mode using the font in ROM. Alternatively, users could install a custom ROM chip that contained lowercase letters in the font; or purchase one of several third-party 80-column cards that enabled a text mode that could display 80-column, upper- and lower-case text. The "Videx Videoterm" card and its many clones were especially popular. For lowercase input, since it was not possible to detect whether the keyboard's Shift keys were in use, a modification called the "one-wire shift key mod" wired the Shift keys to one of the pins on the motherboard's joystick connector. Compatible applications, including nearly all word processors, could then detect whether the Shift key was being pressed. This modification, however, involved soldering, and was therefore only popular among hobbyists.
Apple IIe
The Apple II Plus was followed in 1983 by the Apple IIe, a cost-reduced yet more powerful machine that used newer chips to reduce the component count and add new features, such as the display of upper and lowercase letters and a standard 64 KB of RAM. The IIe RAM was configured as if it were a 48K Apple II Plus with a language card; the machine had no slot 0, but instead had an auxiliary slot that for all practical purposes took the place of slot 3, the most commonly used slot for 80 column cards in the II Plus. The auxiliary slot could accept a 1K memory card to enable the 80-column display. This card contained only RAM; the hardware and firmware for the 80-column display was built into the Apple IIe, remaining fairly compatible with the older Videx-style cards, even though the low-level details were very different. An "extended 80-column card" with more memory expanded the machine's RAM to 128 KB. As with the language card, the memory in the 80-column card was bank-switched over the machine's main RAM; this made the memory better suited to data storage than to running software, and in fact the ProDOS operating system, which was introduced with the Apple IIe, would automatically configure this memory as a RAM disk upon booting. Third-party aux-slot memory cards later allowed expansion up to 1 MB. The 1K 80-column card also enabled one new graphics mode, Double Lo-Res (80 × 48 pixels); the extended 80-column card enabled two, Double Lo-Res and Double Hi-Res (560 × 192 pixels). Both modes doubled the horizontal resolution in comparison to the standard Lo-Res (40 × 48) and Hi-Res (280 × 192) Modes; in the case of Double Hi-Res, the number of available colors was increased as well, from 6 to 15. Only Apple IIe's from the very first production run cannot use Double Hi-Res. Neither of these modes was directly supported by the built-in BASIC, however, so the user had to resort to the use of lots of POKE and CALL commands, or assembly language programming, or one of a number of software Toolkits to exploit these modes.
Introduced with the IIe was the DuoDisk, essentially two Disk II 5¼" drives in a single enclosure designed to stack between the computer and the monitor, and a new controller card to run it. This controller was (by design) functionally identical to the original Disk II controller but used a different connector, allowing a single cable to control both drives in the DuoDisk. The DuoDisk was plagued by reliability problems, however, and did not catch on as well as the IIe itself.
The IIe was the most popular Apple II ever built and was widely considered the "workhorse" of the line. It also has the distinction of being the longest-lived Apple computer of all time -- it was manufactured and sold with only minor changes for nearly eleven years. In that time, following the original, two important variations came to pass known as the Enhanced IIe (four new replacement chips to give it the same features as the later model Apple IIc, including an upgraded processor called the 65C02) and Platinum IIe (a modernized new look for the case color to match other Apple products of the era, along with the addition of a built-in numeric keypad). An Enhanced IIe with 128K of RAM can be considered the minimum requirement for running most Apple II software released after about 1988.
Two and a half years before the Apple IIe, Apple had produced and marketed a computer called the Apple III for business users. This product was not a success, and Steve Wozniak has been quoted as saying that the Apple III had a 100% failure rate -- every single machine manufactured had some kind of fault. Many of its features were carried over in the design of the Apple IIe, though, including the ProDOS operating system, which was based on Apple III SOS.
Apple IIc
Apple released the Apple IIc in April 1984, billing it as a portable Apple II. (By portable it was meant that the computer could be easily carried from place to place; lacking battery power and a built-in display, it was not a true portable as the term is used today.) The IIc even sported a carrying handle that folded down to prop the machine up in a typing position. It was the first of three Apple II models to be made in the Snow White design language -- and the only one that was actually white. (The other machines, the Apple IIGS and the IIc Plus, were actually light gray, or as Apple had it, "platinum.")
The Apple IIc was the first Apple II to use the updated 65C02 processor, and featured a built-in floppy drive and 128K RAM, with a built-in disk controller that could control external drives, composite video (NTSC or PAL), serial interfaces for modem and printer, and a joystick/mouse port. Unlike previous Apple II models, the IIc had no internal expansion slots at all, this being the means by which its compact size was attained. Third parties did eventually figure out how to wedge up to 1 MB of additional memory and a real-time clock into the machine, and a later revision of the motherboard provided an expansion slot that could accept an Apple memory card bearing up to 1 megabyte of RAM. The disk port, originally intended for a second 5¼" floppy drive, eventually was able to interface to 3½" disk drives and (via third parties) even hard disks.
To play up the portability, two different monochrome LCD displays were sold for use with the IIc's video expansion port, although both were short-lived due to high cost and poor legibility. (A IIc with the smaller of these displays appeared briefly in the film 2010.) The IIc had an external power supply that converted AC power to 12V DC, allowing third parties to offer battery packs and automobile power adapters that connected in place of the supplied AC adapter.
The Apple IIc was the first microcomputer to include support for the Dvorak Simplified Keyboard, which was activated using a switch above the keyboard. This feature was also later found in late-model Apple IIe computers (though the switch was inside the computer) and in the Apple IIGS (accessible via the built-in control panel).
Apple IIGS
The next member of the line was the Apple IIGS computer, released in 1986. A radical departure from the existing Apple II line, the IIGS featured a true 16-bit microprocessor, the 65C816, operating at 2.8 MHz with 24-bit addressing, allowing expansion up to 8 MB of RAM without the bank-switching hassles of the earlier machines. It introduced two completely new graphic modes sporting higher resolutions and a palette of 4,096 colors; however, only 4 (at 640 × 200 resolution) or 16 (at 320 × 200 resolution) colors could be used on a single line at a time, although a technique known as dithering was often employed in software to increase the number of perceived colors.
In a welcome departure from earlier Apple II graphics modes, the new modes laid out the scanlines sequentially in memory. However, programmers in search of a graphics challenge could always turn to 3200-color mode, which involved precisely swapping in a different 16-color palette for each of the screen's 200 scanlines as the monitor's electron beam traced the screen line by line. This exotic technique did not leave many CPU cycles available for other processing, so this "mode" was best suited to displaying static images.
The Apple IIGS stood out from any previous (or future) Apple II models, evolving and advancing the platform into the next generation of computing while still maintaining near-complete backward compatibility. The secret of the Apple IIGS's compatibility was a single chip called the Mega II, which contained the functional equivalent of an entire Apple IIe computer (sans processor), which, combined with the flawless 65C02 emulation mode of the 65C816 processor, provided full support for legacy software.
The computer also included a 32-voice Ensoniq wavetable music synthesizer with 64K dedicated RAM, 256K of standard RAM, built-in peripheral ports (switchable between IIe-style card slots and IIc-style onboard controllers for disk drives, mouse, RGB video, and serial devices), built-in AppleTalk networking, and a ROM toolbox that supported a graphical user interface derived from the Macintosh toolbox. The computer could run existing 8-bit Apple II software (including software written for the very first Apple II in Integer BASIC), but also supported 16-bit software running under a new OS first called ProDOS 16 and later called GS/OS. The new OS eventually included a Finder that could be used for managing disks and files and opening documents and applications, along with desk accessories -- just like the Macintosh. The 16-bit operating system would automatically switch to the text display and downshift to 8-bit mode to run legacy software, while offering a consistent, Macintosh-like graphical interface for native 16-bit applications. Eventually the IIGS gained the ability to read and write Macintosh disks and, through third-party software, even multitasking (both cooperative and preemptive, the latter in the form of a Unix-type shell), outline TrueType font support, and in one case, even real-time 3D gaming using texture mapping.
The first 50,000 Apple IIGS computers came with Steve Wozniak's "Woz" signature silkscreened on the front and were referred to as the "Woz Limited Edition." These machines are not functionally different from machines from the same time period without the signature.
The Apple IIGS with 1 Megabyte of built-in RAM (better known as the "ROM 3"), was introduced in late 1989. Along with the additional built-in memory, the ROM 3 contained improvements to the firmware and cleaner sound output. Connector locations that had enabled the previous IIGS motherboard to be installed in an Apple IIe case were eliminated to save costs. Most users considered the ROM 3 a minor maintenance update rather than a new model.
Apple IIc Plus
The final Apple II model was the Apple IIc Plus introduced in 1988. It was the same size and shape as the IIc that came before it, but the 5¼" floppy drive had been replaced with a 3½" drive, the power supply was moved inside (gone was the IIc's "brick on a leash" power supply), and the processor was a fast 4MHz 65C02 processor that actually ran 8-bit Apple II software faster than the IIGS. (Third-party accelerators for other models could, however, go as fast as 10MHz, and IIGS accelerators would eventually reach 16MHz.) The IIc Plus's accelerator was derived from a design licensed from Zip Technologies, a third-party maker of accelerators for the Apple II, though Apple used separate chips instead of combining the processor, cache, and supporting logic on a multi-chip module as did Zip. Like later models of the original Apple IIc, the IIc Plus included a memory expansion slot that would accept a daughtercard carrying up to a megabyte of RAM. The IIc Plus also featured a new keyboard layout that matched the Platinum IIe and IIGS.
Many perceived the IIc Plus as Apple's attempt to compete with the Laser 128EX/2, a popular third party Apple-compatible machine that also had an accelerated processor and a built-in 3½" drive. There were few other rational explanations for Apple expending resources on the continued development of a new 8-bit Apple II model rather than furthering the 16-bit Apple IIGS. However, with its 3½" drive and speedy processor, it was an excellent, compact machine for running the AppleWorks integrated productivity package, especially with the 1 megabyte memory upgrade.
Apple IIe Card
Although not an extension of the Apple II line, in 1990 the Apple IIe Card, an expansion card for the LC line of Macintosh computers, was released. Essentially a miniaturized Apple IIe computer on a card (utilizing the Mega II chip from the Apple IIGS), it allowed the Macintosh to run 8-bit Apple IIe software through hardware emulation (although video was emulated in software and was slower at times than a IIe). Many of the LC's built-in Macintosh peripherals could be "borrowed" by the card when in Apple II mode (i.e. extra RAM, 3½" floppy, AppleTalk networking, hard disk). The IIe card could not, however, run software intended for the 16-bit Apple IIGS. The Macintosh LC with IIe Card was intended to replace the Apple IIGS in schools and homes and was presumably the reason a new model Apple IIGS that was confirmed by insiders to be in development at one point was cancelled and never released.
Other Peripheral Cards
There were many companies during the 80's that provided the Apple II line of computers peripheral cards that added functionality thanks to Steve Wozniak's slot design. One such company was Applied Engineering. Two of the most popular and successful cards were the RamWorks (and its successors, the RamWorks II and RamWorks III) and the TransWarp cards. The RamWorks III card replaced the Apple IIe's auxiliary-slot memory card and with the appropriate daughter board could hold a whopping 3 MB of RAM. The TransWarp card was an Accelerator Card that could speed up the Apple II from its native 1 MHz processor to 3.6 MHz for the TransWarp and 8 MHz for the TransWarp II. Applied Engineering also developed and sold a 1.44-MB 3.5" disk drive, an improvement over Apple's own 800-kB UniDisk 3.5 (for the Apple IIe and IIc) and Apple 3.5 Drive (for the Apple IIGS. The Applied Engineering or AE drive came with its own peripheral card and appropriate cable.
Another card available from Apple Computer was the Apple II ProFile card. This card attached to the Apple ProFile Hard Disk that was initially designed for the Apple III computer. The ProFile was available first in a 5 MB configuration and later in a 10 MB one.
The Final Years
Apple's Macintosh product line finally eclipsed the Apple II in the early '90s. Even after the introduction of the Macintosh, the Apple II had remained Apple's primary source of revenue for years: the Apple II and its associated community of third-party developers and retailers was once a billion-dollar-a-year industry. The computer was the first to attract a loyal user community, and many outspoken Apple II fans were bitter that the company had invested its Apple II profits into the Macintosh rather than using them to further the Apple II series.
Despite a lack of advertising and little corporate support, Apple continued to sell the IIGS through the end of 1992. Apple brought an era to a close when the IIe was removed from the product line on October 15, 1993.
Clones
Like the IBM PC, the Apple II was frequently cloned, both in the United States and abroad. According to some sources (see below), more than 190 different models of Apple II clones were manufactured. Many of these had "fruit" names (e.g. "Pineapple") to indicate to the initiated that they were Apple II clones. For many years the most widely-used microcomputers in the Soviet Bloc were the Agat, an over-sized Russian Apple II clone with a Cyrillic character set, and Bulgarian Pravetz-8 series, an almost direct replicas of Apple II models with Cyrillic support.
An Australian-produced clone of the Apple II was the Medfly, named after the Mediterranean fruit fly that attacks apples. The Medfly computer featured a faster processor, more memory, detached keyboard, lower and upper case characters and a built-in disk controller.
The Ace clones from Franklin Computer Corporation are the best known and had the most lasting impact, as Franklin copied Apple's ROMs and software and freely admitted to doing so. Franklin's argument: a computer's ROM was simply a pattern of switches locked into a fixed position, and one cannot copyright a pattern of switches. Apple fought Franklin in court for about five years to get its clones off the market, and was ultimately successful when a court ruled that software stored in ROM was in fact copyrightable. Franklin later released non-infringing but less-compatible clones; these could run ProDOS and AppleWorks and had an Applesoft-like BASIC, but compatibility with other software was hit-or-miss.
Apple also challenged VTech's Laser 128, an enhanced clone of the Apple IIc first released in 1984, in court. This suit proved less fruitful for Apple, because VTech had reverse-engineered the Monitor ROM rather than copying it and had licensed Applesoft BASIC from its creator, Microsoft. Incredibly, Apple had neglected to obtain exclusive rights to the Applesoft dialect of BASIC from Microsoft; just as incredibly, VTech was the first cloner to bother licensing it. The Laser 128 proved popular and remained on the market for many years, both in its original form and in enhanced versions that ran faster than 1 MHz. Although it wasn't 100% compatible with the Apple II, it was close, and its popularity ensured that most major developers tested their software on a Laser as well on as genuine Apple machines. Because it was frequently sold via mail order and mass-market retailers such as Sears, the Laser 128 may have cut into the sales of low-cost competitors such as Commodore Business Machines as much as it did Apple's.
While the first Apple II clones were generally exact copies of their Apple counterparts that competed mainly on price, many clones had extra capabilities too. A Franklin model, the Ace 1000, sported a numeric keypad and lower-case long before these features were added to the Apple II line. The Laser 128 series is sometimes credited with spurring Apple to release the Apple IIc Plus; the built-in 3½" drive and accelerated processor were features Laser had pioneered. The Laser 128 also had a IIe-style expansion slot on the side that could be used to add peripheral cards.
Bell & Howell, an audiovisual equipment manufacturer whose products (particularly film projectors) were ubiquitous in American schools, offered what appeared at first glance to be an Apple II Plus clone in a distinctive black plastic case. However, these were in fact real Apple II Pluses manufactured by Apple for B&H for a brief period of time. Many schools had a few of these "black Apples" in their labs.
Unitron, a Brazilian company, produced another clone, named ApII. Unitron used a copy of the Apple's ROM, translated to Portuguese. The operating system was the Apple's DOS 3.3 translated to Portuguese. During this period, it was illegal to import microcomputers in Brazil and buying those (illegal) clones was the only way to have a microcomputer. Unitron stopped manufacturing APII few years after the introduction of the IBM PC's clones in Brazil.
General
Apple II media
Originally the Apple II used audio cassette tapes for program and data storage. Apple and many third-party developers made software available on tape until the introduction of the Disk II.
The Disk II floppy drive used 5¼-inch floppy disks. The first disk operating systems for the Apple II were DOS 3.1 and DOS 3.2, which stored 113.75 kB (1 kB = 1024 bytes) on each disk, organized into thirty-five tracks of thirteen 256-byte sectors each. After about two years, DOS 3.3 was introduced, storing 140 kB thanks to a minor hardware change on the disk controller that allowed it to store 16 sectors per track. (This upgrade was user-installable on older controllers.) After the release of DOS 3.3, the user community discontinued use of DOS 3.2 except for running legacy software. Programs that required DOS 3.2 were fairly rare, however, as DOS 3.3 was not a major architectural change aside from the number of sectors per track. A program called MUFFIN was provided with DOS 3.3 to allow users to copy files from DOS 3.2 disks to DOS 3.3 disks.
On a DOS 3.x disk, tracks 0, 1, and most of track 2 were reserved to store the operating system. A short ROM program on the disk controller had the ability to seek to track zero -- which it did without regard for the read/write head's current position, resulting in the characteristic "chattering" sound of a Disk II boot, which was the read/write head hitting the rubber stop block at the end of the rail -- and read and execute code from sector 0. The disk's directory was stored on track 17, smack in the middle of the 35-track disks, in order to reduce the average seek time to the frequently-used directory track. The directory was fixed in size and could hold a maximum of 105 files. Subdirectories were not supported.
Most game publishers did not include DOS on their floppy disks, since they needed the memory it occupied more than its capabilities; instead, they often wrote their own boot loaders and read-only file systems. This also served to discourage "crackers" from snooping around in the game's copy-protection code, since the data on the disk wasn't in files that could be accessed easily.
Some third-party manufacturers produced floppy drives that could write 40 tracks to most 5¼-inch disks, yielding 160 kB of storage per disk, but the format did not catch on widely, and no known software was published on 40-track media. Most drives, even Disk IIs, could write 36 tracks; simple modifications to DOS for formatting the extra track were common.
Incidentally, although the Apple Disk II stored 140 kB on single-sided, "single-density" floppy disks, it was very common for Apple II users to extend the capacity of a floppy disk to 280 kB -- by cutting out a write-protect notch on the side of the disk using a "disk notcher" (although a simple hole puncher would do) and inserting the disk flipped over. The rationalization for this questionable technique was that manufacturers of single-sided floppy disks in those days tested only one side -- but the Apple Disk II used the other when a disk was inserted normally.
Later, Apple IIs were able to use 3½-inch disks with a total capacity of 800 kB and hard disks. DOS 3.3 did not support these drives natively; third-party software was required, and disks larger than about 400 kB had to be split up into multiple "virtual disk volumes." ProDOS, a 1983 descendent of the Apple ///'s SOS, became the Apple II operating system of choice for users with these larger disks thanks to its native support of volumes up to 32 MB in size and the fact that AppleWorks required it.
Renditions of the "II" name
The "II" portion of the Apple II name was rendered in a variety of creative ways using punctuation symbols on the front lids of the computers, and most printed material followed this lead. The II and the "unenhanced" IIe were labeled ][ and ][e, and the IIGS and IIc Plus were rendered in small caps. The Apple ///, IIc, and later IIe models used slashes: ///, //c and //e. All this variation occasioned much error, so many other forms have been used.
Life after death
Today, emulators for various Apple II models are available to run Apple II software on the Macintosh, Linux, Microsoft Windows, and other operating systems. Numerous disk images of Apple II software are available free over the Internet for use with these emulators. However, emulators cannot run software on copy-protected media unless somebody "cracks" (removes the copy restrictions from) the software. The Lost Classics Project had as its goal convincing copyright holders of classic Apple II software to officially allow unrestricted free distribution of their software and has "freed" a number of programs.
One unusual homage to the Apple II is an XScreenSaver "hack" named bsod. The bsod screensaver duplicates the appearance of computer crash screens for various operating systems (including the Windows Blue Screen of Death, after which it is named). In the case of the Apple II, the screensaver actually emulates the CRT display typically used with the computer, so the screen will appear to twitch as text blocks turn on and off, a common quirk of analog NTSC displays. Another module called "Apple2" shows a working Apple II being used to type and run three different BASIC programs, also with glitch-complete CRT emulation and even typos (or "syntax errors").
Industry impact
It is difficult to estimate the enormous impact that the Apple II family of computers has had on world business and, especially, the technology industry. The Apple II was the first computer many people ever saw, and it was affordable enough for middle-class families. Its popularity bootstrapped the entire computer game and the educational software markets and began a boom in the word processor and computer printer markets. The first microcomputer "killer app" for business was VisiCalc, the first spreadsheet, and it ran first on the Apple II; many businesses bought Apple IIs just to run VisiCalc. Apple's success in the home market inspired competitive home computers such as the VIC-20 (1980) and Commodore 64 (1982), which through their significantly lower price point introduced computers to several million more home users -- grabbing some of Apple's market share in the process.
The success of the Apple II in business spurred IBM to create the IBM PC, which was then purchased by middle managers in all lines of business in order to run spreadsheet and word processor software, at first ported from Apple II versions; later, whole new application software dynasties would be founded on the PC. The popularity of these PCs and their clones then transformed business again with LAN applications such as e-mail and later Internet applications such as Usenet and the WWW.
One valuable lesson from the Apple II was the importance of an open architecture to the success of a computer platform. The first Apple IIs shipped with an Apple II Reference Manual containing a complete schematic of the entire computer's circuitry and a complete source listing of the "Monitor" ROM firmware that served as the machine's BIOS. The Apple II's slots, allowing any peripheral card to take control of the bus and directly access memory, enabled an independent industry of card manufacturers who together created a flood of hardware products that let users build systems that were far more powerful and useful (at a lower cost) than any competing system, most of which were not nearly as expandable and were universally proprietary. Even the game port was unusually powerful and could be used for digital and analog input and output; one hacker used it to drive a LaserWriter printer.
Apple decided not to create an open architecture with the initial Macintosh models, and this is widely seen as having hobbled its success, although the IBM PC provides an object lesson that success for the platform does not necessarily equate to success for the company that invented it. In the end, the IBM PC's off-the-shelf, open architecture allowed clones to be manufactured by startup competitors such as Compaq, Dell, Gateway, and countless others, leading to a Pyrrhic victory for IBM and, eventually, the company's abandonment of the personal computer business in 2005.
See also
- Apple Computer
- Apple IIe
- Apple IIc
- Apple IIc Plus
- Apple IIGS
- Apple II peripheral cards
- Apple III
- List of Apple II application software
- List of Apple II games
- List of Apple II emulators
- List of Apple IIgs games
- Steve Wozniak
- Juiced.GS – The last remaining Apple II publication
- Publications/Periodicals devoted to the Apple II
- List of BBS software – For the Apple II and other machines
References
- Wozniak, Steve. "System Description: The Apple II". BYTE. May 1977. [1]
External links
- A2Central.com – Apple II news and downloads
- comp.sys.apple2 – (Usenet newsgroup) – most active free Apple II user forum
- Steven Weyhrich's Apple II History
- Dmoz.org - Apple II
- Apple II expansion cards
- PCB pictures of the Apple II
- Apple2clones has information on Apple II clones
- Applefritter has an Apple II forum
- Apple2Guide.net – Beginner's guide and reference.
