Science Fair Project Encyclopedia
Apple II family
The Apple II family was the first series of microcomputers made by Apple Computer, in the late 1970s and early-to-mid 1980s. Completely different from Apple's later Macintosh computers, the Apple II was a predominantly 8-bit architecture.
The progenitor was the Apple I, which was a hand-built machine sold to hobbyists. It was never produced in quantity, but pioneered many of the features that would make the Apple II a success. The first large-scale production computer was the Apple II. It became popular with home users, as well as occasionally being sold to business users, particularly after the release of the first ever spreadsheet on any computer, VisiCalc. 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 and IIGS.
The "II" portion of the name was alternately rendered in a variety of creative ways using punctuation symbols. For example, the II and the "unenhanced" IIe was most commonly written ][ and ][e, and the IIc and enhanced, platinum IIe models were written as //c, and //e. Finally, the IIgs and IIc plus were rendered in the form as used in this article.
The original Apple II
The first Apple II computers went on sale starting on June 5, 1977 with a MOS Technology 6502 microprocessor running at 1 MHz, 4 KB of RAM, an audio cassette interface, 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 for display on a monitor, or on a TV set by way of an RF modulator. Users could save and retrieve programs and data on audio cassettes; other programming languages, games, applications and other software were available on cassette too. The original retail price was $1298 with 4KB of RAM and $2638 with 48KB of RAM.
Later, an external 5¼-inch floppy disk drive, the Disk II, with controller card that plugged into one of the computer's slots, enabled much more convenient data storage and retrieval. This disk drive interface created by Steve Wozniak is still regarded as an engineering design marvel. The controller card had very little hardware support, relying on software timing loops instead to provide the necessary encoding; the controller also used a form of Group Code Recording, which was simpler and easier to implement in software than the more common MFM. That reduced the overall cost significantly, leaving the total system price low enough for home users. It also made it easy for proprietary software developers to make the media on which their applications shipped hard to copy by using tricks such as changing the low-level sector format or even stepping the drive's head between the tracks; however, other groups eventually sold software such as Copy II Plus and Locksmith that could foil such restrictions.
Wozniak's open design and the Apple's multiple expansion slots permitted a wide variety of third-party devices to expand the capabilities of the machine. 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 such as the dBase II database and the WordStar word processing program. 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. Even so-called accelerator boards were eventually created which would double or quadruple the computer's speed.
The family grows
The Apple II was eventually superseded by the Apple II Plus, which included the Applesoft BASIC programming language (which added support for floating-point arithmetic but sacrificed integer performance in the process) in ROM (previously available as an upgrade) and had a total of 48 kilobytes of RAM, expandable to 64 KB through a "language card" that let users quickly switch between "INT" (Integer) and "FP" (Applesoft) dialects of BASIC (but destroying any unsaved program in the process). Addition of the language card also enabled the use of UCSD Pascal and FORTRAN 77 compilers, released for the Apple at that time.
This was followed by the Apple IIe, a cost-reduced version, that used newer chips to reduce the overall component count. It also displayed both upper and lowercase letters and had 64 KB of RAM expandable to 128 KB. The IIe could also display high resolution text (80 columns) with an add-in 80 column card. The IIe was probably the most popular Apple II and was widely considered the "workhorse" of the line.
About the same time, a computer called the Apple III was produced. This was marketed to business users and was never successful. Steve Wozniak has been quoted as saying that the Apple III had a 100% failure rate.
Apple later produced their first portable Apple II called the Apple IIc. It used the updated 65C02 processor and featured onboard controllers for common devices such as disk drives, modems, etc., that previously required adapter cards. However, due to its compact design, the Apple IIc had limited expandability. The Apple IIc was codenamed the "Lolly" in certain internal and prerelease documents.
Shortly after introducing the Apple IIc, Apple produced an Enhanced Apple IIe that used the 65C02 processor. A final version of the IIe known as the Platinum Apple IIe was introduced later; it added a numeric keypad, built in 80 column support and used a different color of case from earlier IIe versions.
The next (and most powerful) member of the line was the Apple IIGS computer, released in 1986. The IIGS featured a 2.8 MHz 65C816 processor with 16-bit registers and 24-bit addressing, more memory, better color, more peripherals (switchable between IIe-style card slots and IIc-style onboard controllers), and a user interface derived from Mac OS.
The last Apple II was the Apple IIc Plus, introduced in 1988. It was about the same size as the IIc that came before it, but the 5¼" floppy drive was replaced with a 3½" drive, the power supply was moved inside (with the IIc, most of the supply was in an external "brick-on-a-leash"), and a built-in 4MHz accelerator (licensed from Zip Technologies). The latter made the IIc Plus the fastest Apple II out-of-the-box (add-in accelerators for earlier models would frequently exceed this speed; the IIe and IIc could go as fast as 10MHz with the RocketChip accelerator, while the ZipGS could take the IIGS to 12MHz or faster).
Apple's Macintosh product line eclipsed Apple II sales around 1986. Apple did continue to sell and support the IIGS until 1992-1993, largely due to their use in schools. They did support the IIe into 1996, this was due to many video game systems being based on the same chip as the IIe, most notably the NES, allowing for easier testing of game code on the IIe than on a PC or Mac.
Like the IBM PC, the Apple II was frequently cloned, both in the United States and abroad. According to the web site apple2clones.com, there are 168 known clones in existence.
However, the Apple II 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. Apple's challenges to Franklin led to copyright law being extended to include computer software. Apple fought Franklin for about five years to get its clones off the market, and was ultimately successful.
Apple also challenged VTech's Laser 128, which was a clone of the Apple IIc first released in 1984. It was unsuccessful, because VTech had reverse-engineered the ROMs rather than copying them, and the Laser 128 proved popular and remained on the market for many years. Because it was frequently sold via mail order and mass-merchant retailers, the Laser 128 may have impacted low-cost competitors such as Commodore Business Machines as much as it did Apple.
While the first Apple II clones were generally exact copies of their Apple counterparts, later clones tended to add capabilities in addition to undercutting Apple's price.
Apple II media
Traditionally, Apple II family computers used 140K capacity 5¼-inch disks. Later Apple IIs could use 3½-inch disks with a total capacity of 800K. Less common were Apple II computers outfitted with an Apple Profile hard drive, which had a total capacity of 5 MB.
Life after death
Nowadays, even a PC running Microsoft Windows can emulate the important Apple II models with emulator software such as AppleWin by copying the disk through a serial line. However emulators cannot run software on copy-restricted media unless somebody "cracks," or removes the copy restrictions from, the software. Numerous disk images for Apple II software are available free over the Internet. There is a movement afoot to convince the copyright holders of classic Apple II software to officially allow unrestricted free distribution of their software.
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, for which it is named). In the case of the Apple II, the screensaver actually emulates the CRT display used back then, so the screen will appear to twitch as text blocks turn on and off. Another module, called "Apple2" shows a working Apple II being used to type and run three different BASIC programs, also with CRT emulation and even typos (or "syntax errors").
It is difficult to estimate the 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 that most people had ever seen, and it was affordable for middle-class families. Its popularity enabled the entire computer game market; the educational software market; a boom in the word processor and computer printer market; and the absolute "killer app" for business: VisiCalc, the first spreadsheet. VisiCalc alone sold many Apple II's to many business people. On the other hand, the success in the home market inspired the creation of many other inexpensive 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 also goaded 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 (which at first was ported from the Apple II versions, and later inspired whole new application software franchises). The strong popularity of these PCs and their clones then transformed business again with LAN applications such as e-mail and the later use of PCs to access the Usenet and the WWW.
One valuable lesson from the first Apple II computers was the importance of an open architecture to a particular platform. The computer's slots, allowing any peripheral card to take control of the bus, enabled an independent industry of card manufacturers who together created a flood of products that let users build systems that were far more powerful and useful (at a lower cost) than could possibly have occurred if Apple had kept its system proprietary. Apple failed to create an open architecture with the initial Macintosh models, and this is widely seen as having hobbled its potential success. IBM did create its IBM PC with an open architecture, which helped its wild success, though in the end IBM was unable to control the creation of clones, and has been eclipsed by competitors such as Dell, Compaq/Hewlett-Packard, and Gateway.
- Steven Weyhrich's Apple II History
- Dmoz.org - Apple II
- Apple II expansion cards
- Applefritter has some Apple I information
- Some nice PCB pictures
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