Apple IIe

Mac_specs|
ProDOS|RAM=64 KB (up to 1 MB+)|RAMtype=| Discontinued=November 1993The Apple IIe is the third model in the Apple II series of personal computers produced by Apple Computer. The "e" in the name stands for "enhanced", referring to the fact that several popular features were now built-in that were only available as upgrades and add-ons in earlier models. It also improved upon expandability and added a few new features, which, all combined, made it very attractive to first-time computer shoppers as a general-purpose machine. The Apple IIe has the distinction of being the longest-lived computer in Apple's history, having been manufactured and sold for nearly 11 years with relatively few changes. For this reason, it is the most commonly recognized model in the Apple II line.

History

The beginning

Apple had planned to retire the Apple II series after the introduction of the Apple III in 1980, however, after that machine turned out to be a disastrous failure, management decided the further continuation of the Apple II was in the company's best interest. So, after three and a half years at a stand-still, came the introduction of a new Apple II model—the Apple IIe (codenamed "Diana" and "Super II"). The Apple IIe was released in January 1983, the successor to the Apple II Plus. Some of the hardware and software features of the Apple III were borrowed in the design of the Apple IIe. The culmination of these changes led to increased sales and greater market share of both home and small business use.

Overview of new features

One of the most notable improvements of the Apple IIe is the addition of a full ASCII character set and keyboard. The most important addition is the ability to input and display lower-case letters. Other keyboard improvements include four-way directional cursor control and standard editing keys (Delete and Tab), two special Apple modifier keys (Open and Solid Apple), and a safe off-to-side relocation of the "Reset" key. The auto-repeat function (any key held down to repeat same character continuously) is now automatic, no longer requiring the "REPT" key (now gone) found on the previous model's keyboard.

The machine came standard with 64 KB RAM, with the equivalent of a built-in Apple Language Card in its circuitry, and had a new special "Auxiliary slot" (replacing slot-0, though electronically mapped to slot-3 for compatibility with earlier third-party 80 column cards) for adding more memory via bank-switching RAM cards. Through this slot it also includes built-in support for an 80 columns text display on monitors (with the addition of a plug-in 1K memory card, via bank-switching of 40 columns) and could be easily doubled to 128 KB RAM by alternatively plugging in an Apple's Extended 80 Columns Card. As time progressed even more memory could be added through third party cards using the same bank-switching slot, or alternatively general purpose slot cards that addressed memory 1 byte at a time (i.e. Slinky RAM cards). A new ROM diagnostic routine could be invoked to test the motherboard for faults and its main bank of memory.

The Apple IIe lowered production costs and improved reliability by merging the function of several off-the-shelf ICs into single custom chips, reducing total chip count to 31 (previous models used 120 chips). For this reason the motherboard design is much cleaner and runs cooler as well, with enough room to add a pin-connector for an (optional) external numeric keypad. Also added was a backport accessible DE-9 joystick connector, making it far easier for users to add and remove game and input devices (previous models requiring plugging the joystick/paddles directly into a 16-pin DIP socket on the motherboard; the IIe retained this connector for backwards compatibility). Also improved were port openings for expansion cards. Rather than cutout V-shaped slot openings as in the Apple II and II Plus, the IIe has a variety of different sized openings, with thumb-screw holes, to accommodate mounting interface cards with DB-xx and DE-xx connectors (removable plastic covers filled the cutouts if not used). The Apple IIe maintains full backwards compatibility with the previous two Apple II models, allowing most hardware and software from those systems to be used.

Technical specifications

Microprocessor
* 6502 or 65C02 running at 1.023 MHz
* 8-bit data busMemory
* 64 KB RAM built-in
* 16 KB ROM built-in
* Expandable from 64 KB up to 1 MB RAM or moreVideo modes
* 40 and 80 columns text, white-on-black, with 24 lines¹
* Low-Resolution: 40×48 (16 colors)
* High-Resolution: 280×192 (6 colors) *
* Double-Low-Resolution: 80×48 (16 colors)
* Double-High-Resolution: 560×192 (16 colors) *

"*effectively 140×192 in color, due to pixel placement restrictions"

"¹Text can be mixed with graphic modes, replacing either bottom 8 or 32 lines of graphics with 4 lines of text, depending on video mode"

Audio
* Built-in speaker; 1-bit toggling
* Built-in cassette recorder interface; 1-bit toggle output, 1-bit zero-crossing inputExpansion
* Seven Apple II Bus slots (50-pin card-edge)
* Auxiliary slot (60-pin card-edge)Internal connectors
* Game I/O socket (16-pin DIP)
* RF modulation output (4-pin Molex)
* Numeric keypad (11-pin Molex)External connectors
* NTSC composite video output (RCA connector)
* Cassette in/out (two 1/8" mono phono jacks)
* Joystick (DE-9)

Revisions

In production from January 1983 until November 1993, the Apple IIe remained relatively unchanged through the years. However there was one significant motherboard update, a major firmware update, two cosmetically revised machines and an official compatible from Apple, in the form of slot card for the Macintosh computer. These revisions are detailed below.

The Revision A motherboard

At the time of the Apple IIe's introduction, and well into the first few months of production, this motherboard shipped with all units. Graphics modes supported are identical, and limited to, that of the Apple II Plus before it. The logic board is not compatible with the ROM based firmware update (introduced some years later) and most newer plug in expansion slot cards.

The Revision B motherboard

Shortly after the "Revision A" motherboard's release in 1983, engineers discovered that the bank-switching feature (which used a paralleled 64 KB of RAM on the Extended 80 Columns Card; or 1 KB to produce 80 columns using bank-switching) could also be used to produce a new graphics mode, Double-High-Resolution, with double the horizontal resolution and number of colors of standard High-Resolution. In order to support this, some modifications had to be made to the motherboard, which became the Revision B. In addition to supporting Double-High-Resolution and Double-Low-Resolution (see list above) it also added a special video signal accessible in slot-7.

Apple upgraded the motherboard free of charge. In later years Apple labeled newer IIe motherboards with a "-A" suffix once again, although in functionality they were Revision B motherboards.

New case and keyboard

In 1984, Apple revised the case and keyboard. The original IIe uses a case very similar to the Apple II Plus, painted and with Velcro-type clips to secure the lid with a strip of metal mesh along the edge to eliminate Radio Frequency Interference. The new case is made of dyed plastic mold in a slightly darker beige with a simplified snap-case lid. The other noticeable change is a new keyboard, with more professional looking print on darker keycaps (small black lettering, versus large white print). This was the first cosmetic change.

The Enhanced IIe

In March 1985, Apple replaced the original machine with a new revision called the Enhanced IIe. It is completely identical to the previous machine except for 4 chips changed on the motherboard (and a small "Enhanced" or "65C02" sticker placed over the keyboard power indicator). The purpose of the update was to make the Apple IIe more compatible with the Apple IIc (released the previous year) and in some respects to a smaller degree, the Apple II Plus. This change involved a new processor, the CMOS based 65C02 CPU, a new character ROM for the text modes, and two new ROM firmware chips. The 65C02 added more CPU instructions, the new character ROM added 32 special "MouseText" characters (which allowed the creation of a GUI-like display in text mode, similar to IBM ANSI), and the new ROM firmware fixed problems and speed issues with 80 columns text, introduced the ability to use lowercase in Applesoft BASIC and Monitor, and contained some other smaller improvements (and fixes) in the latter two (including the return of the Mini-Assembler—which had vanished with the introduction of the II Plus firmware).

Despite affecting compatibility with a small number of software titles (particularly those that did not follow Apple programming guidelines and rules, used illegal opcodes that were no longer available in the new CPU, or used the alternate 80 column character set that MouseText now occupied) a fair bit of newer software — mostly productivity applications and utilities — require the Enhancement chipset to run at all. An official upgrade kit, consisting of these 4 replacement chips and an "Enhanced" sticker badge, was made available for purchase to owners of the original Apple IIe. An alternative at the time, which some users choose as a cost cutting measure, was to simply purchase their own 65C02 CPU and create (unlicensed and illegal) duplicates of the updated ROMs using re-rewritable EPROM chips. When Apple phased out the Enhancement kit in the early 1990s, this became the only method available method for users looking to upgrade their IIe, and remains so right up until present day. An Enhanced machine identifies itself with the name "Apple //e" on its start up splash screen (as opposed to the less specific "Apple ] [").

The Platinum IIe

In January 1987 came the final revision of the Apple IIe, often referred to as the Platinum IIe, due to the color change of its case to the light-grey color scheme that Apple dubbed "Platinum". Changes to this revision were mostly cosmetic to modernize the look of the machine. Besides the color change, there was a new keyboard layout with built-in numeric keypad. The keyboard was changed to match the layout of the Apple IIGS, with the reset key moved above the ESC and '1' keys, the Open and Solid Apple modifier keys replaced by Command and Option and the power LED relocated above the numeric keypad. Gone were the recessed metal ID badges (showing the Apple logo and name, with "//e" beside it) replaced with a simpler "Apple IIe" silk screened on the case lid in the Apple Garamond font. A smaller Apple logo badge remained, however moved to the right side of the case.

Internally, a (reduced in size) Extended 80 Columns Card was factory pre-installed, making it come standard with 128 KB RAM and Double-Hi-Res graphics enabled. The motherboard has a reduced chip count by merging the two system ROM chips into one and used higher density memory chips so its 64 KB RAM could be made up of two (64 Kbx4) chips rather than eight (64 Kbx1) chips, bringing the count down to a total of 24 chips. A solder pad location on the motherboard, present since the original IIe, for (optionally) making presses of the "Shift" keys detectable in software, is now shorted by default so that the feature is always active. Next, in a move to reduce Radio Frequency Interference when a joystick plugs into the motherboard's Game I/O socket, filtering capacitors were added. While this made no difference to the average user, it had the negative effect of lowering the available bandwidth to the socket, which is often used by specialized devices for such purposes as measuring temperature, controlling a robotic device, or even simplistic networking for data transfer to another computer. In such cases the specialized devices were rendered useless on the Platinum IIe unless the user removed the capacitors from the board.

There were no firmware changes present, and functionally the motherboard is otherwise identical to the Enhanced IIe. This final model of the Apple IIe was discontinued in November 1993, officially retiring the entire Apple II family line with it.

The Apple IIe Card for Macintosh

In March 1991, shortly after the release of the Macintosh LC series, Apple released the PDS slot-based Apple IIe Card for the Macintosh. By plugging this card into a Macintosh LC (and later models incorporating an LC PDS slot), through hardware and (some) software emulation, the Macintosh can run most software written for the 8-bit Apple IIe computer. This miniaturized computer on a card was made possible by a chip called the Mega II, first used in the Apple IIGS computer to emulate the Apple IIe. The Mega II duplicates all the functions of a standard Apple IIe, minus RAM, ROM and CPU.

Many of the built-in Macintosh peripherals can be "borrowed" by the card when in Apple II mode (i.e. extra RAM, 3½ floppy, AppleTalk networking, clock, hard disk). It can even run at an accelerated 2 MHz, however as video is emulated using Macintosh QuickDraw routines, in slower machines it sometimes can not keep up with the speed of a real Apple IIe. With a specialized Y-cable, the card can use an actual Apple 5.25, Apple UniDisk 3.5 or even Apple II joystick/paddles. The Apple IIe Card is thought of as an Apple II compatible or emulator rather than an extension of the Apple II line, but included in this article for the sake of completeness.

International versions

The Apple IIe keyboard differed depending on what region of the world it was sold in. Sometimes the differences were very minor, such as extra local language characters and symbols printed on certain keycaps (e.g. French accented characters on Canadian IIe such as "á", "é", "ç", etc, or the British Pound "£" symbol on the UK IIe) while other times the layout and shape of keys greatly differed (e.g. European IIe). In order to access the local character set and keyboard layout, a user-accessible switch is found on the underside of the keyboard -- flipping it will instantly switch the video output and keyboard input from the US character set to the local set. To support this, special double capacity video and keyboard ROMs are used; in early motherboards they had to reside on a tiny circuit card that plugged into the socket. In some countries these localized IIe's also support 50 Hz PAL video instead of the standard 60 Hz NTSC video and the different 220/240 volt power of that region. An equivalent of the "PAL color card" for the earlier Apple II europlus model was integrated into the motherboard of these IIe's, so that color graphics are available without the addition of a slot card.

Another difference with the European IIe, is the Auxiliary slot physically moved in location so it is in line and in front of slot-3, preventing both slots from being used simultaneously for full-sized cards. A few third-party cards are affected by this: some European cards that plug into both slots simultaneously and are thus unusable on American IIe's, and some American cards that don't fit into the case of European IIe's because the European location of the Auxiliary slot leaves less room for them.

Upgrades

The Apple IIGS Upgrade

When the Apple IIGS computer was introduced by Apple Computer in September 1986, Apple also announced it would be making an upgrade kit for the IIe available for purchase. Essentially the "upgrade" replaced the Apple IIe motherboard for a 16-bit Apple IIGS motherboard, making it more of an outright computer transplant than upgrade. Users would bring their Apple IIe machines into an authorized Apple dealership, where the IIe motherboard and lower baseboard of the case were swapped for an Apple IIGS motherboard with a new baseboard (with matching cut-outs for the new built-in ports). New metal sticker ID badges replaced those on the front of the Apple IIe, rebranding the machine. Retained were the upper half of the IIe case, the keyboard, speaker and powersupply. Original IIGS motherboards (those produced between 1986 to mid 1989) have electrical connections for the IIe powersupply and keyboard present, although only about half produced have the physical plug connectors factory pre-soldered in, which were mostly reserved for the upgrade kits.

The upgrade cost US$500, plus the trade-in of the user's existing Apple IIe motherboard and baseplate (and in some cases, the upper half of the IIe case itself for very early Apple IIe units which couldn't accommodate the new baseplate) . It proved unpopular as it did not include a mouse (which is an essential part of the IIgs, much like the Macintosh); the keyboard, although functional, does not mimic all the features and functions of the Apple Desktop Bus keyboard, as well as lacking a numeric keypad; and some cards designed for the new 16-bit machine did not fit in the Apple IIe's slanted case either. In the end most users found they were not saving much, once they had to purchase a 3.5 floppy drive, analog RGB monitor and mouse. Although it could use some IIe peripherals, most of them became obsolete in the upgrade due to their function being already built-in. It did however make an attractive upgrade for Apple IIe users wanting to use the machine strictly in IIe-emulation mode (ignoring the native part of the machine), which provide faster CPU operation, 256 KB RAM, a clock and many built-in peripherals via the backports.

ee also

* Apple II series
* Apple III
* Apple II Plus
* Apple IIc
* Apple IIc Plus
* Apple IIGS
* Apple II peripheral cards
* List of Apple II games
* Publications/Periodicals devoted to the Apple II
* ReactiveMicro.com – The last remaining Apple II hardware production company (cloned items)

References

External links

* [http://www.a2central.com/ A2Central.com] – Apple II news and downloads
* [http://www.apple2history.org/ Steven Weyhrich's Apple II History]
* [http://dmoz.org/Computers/Systems/Apple/Apple_II/ Dmoz.org - Apple II]
* [http://www.mandrake.demon.co.uk/Apple/8bit.html Apple II expansion cards]
* [http://www.applefritter.com/forum/84 Applefritter has an Apple II forum]
* [http://www.8bit-museum.de/?page=docs/apple3b.htm PCB pictures of the Apple II]
* [http://www.apple2clones.com/ Apple2clones has information on Apple II clones]
* [http://www.reactivemicro.com/ ReactiveMicro.com] - The last remaining Apple II hardware production company (cloned items), Enhance Kit
* [http://pagesperso-orange.fr/gtello/a2e_e.htm WEB Page of a user] Some cards detailed and programs to download.