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The Apple IIc, the fourth model in the Apple II line of personal computers, was Apple Computer's first endeavor to produce a portable computer. The end result was a "luggable" notebook sized version of the Apple II which could be easily be transported from place to place. The "c" in the name stood for "compact", referring to the fact it was essentially a complete Apple II computer setup (minus display and powersupply) squeezed into a small notebook sized housing. While it sporting a built-in floppy drive and new rear peripherial expansion ports, it lacked the internal expansion slots and direct motherboard access of earlier Apple II's, making it a closed system. However that was the intended direction for this model--a more appliance like machine, ready to use out of the box, requiring no technical know-how or experience to hook up and therefore attractive to first time users.


File:AppleIIc2.jpg
The Apple IIc, the first portable computer produced by Apple Computer. Seen here with an optional mouse.



History

The Apple IIc was released in April 1984, during an Apple held event called "Apple II Forever". The new machine was proclaimed as proof of Apple's long term commitment to the Apple II series and its users, an assurance the company's older technology would not be foresaken or dropped with the recent introduction of the Macintosh. While essentially an Apple IIe computer in a smaller case, it was not a replacement, but rather a portable version to complement it. One Apple II machine would be sold for users who required the expandability of slots, and another for those wanting the simplicity of a plug and play machine with portability in mind.

The machine introduced Apple's Snow White design language, notable for its elegent case styling and a sleek modern look which soon became the standard for most Apple equippment and computers, and continuing for nearly a decade after. The origin of term comes from the Apple IIc's unique snow white coloring, the only Apple made computer produced in this color (other machines were typically beige or light grey). While relatively light weight and compact in design, the Apple IIc was not a true portable in design as it lacked a built-in battery and display.


Overview of features

Improving the IIe

Technically the Apple IIc was the Apple IIe computer in a smaller case, retaining the same set of features. Building on the design, it did manage to offer a few minor improvement without affecting compatibility. First it utilized the CMOS based 65C02 microprocessor (instead of a plain 6502) which added 27 new processor instruction sets and drew less power. The new ROM firmware allowed Applesoft BASIC to recognize lowercase characters, work better with an 80 columns display and fixed several bugs from the IIe ROM. In terms of video, the text display added 32 unique character symbols called "Mousetext" which when placed side by side, could display simplistic looking icons, windows and menus to recreate a graphical user interface completely out of text, similar in concept to IBM ANSI. Note: A year later the Apple IIe would later benefit from these improvements in the form up a four chip upgrade called the Enhanced IIe.

Built-in cards

The equivalent of five slot cards were built-in and integrated into the Apple IIc motherboard. These included: An Extended 80 Columns Card, two Apple Super Serial Cards, a Mouse Card and a floppy drive controller card. For starters this meant the Apple IIc had 128K RAM, 80 columns text and Double-Hi-Resolution graphics built-in and available right out of the box, unlike its older sibling the Apple IIe. It also meant less of a need for slots as the most popular peripheral add-on cards were already built-in, ready for devices to be plugged into the rear ports of the machine. The built-in cards were mapped to phantom slots so software and hardware devices for older Apple II models would know where to find them (i.e. mouse to vitual slot 4, serial cards to slot 1 and 2, floppy to slot 6, and so on). Of interest is the entire Apple Disk II Card, used for controlling floppy drives, had been shrunk down into a single chip called the "IWM" which stood for Integrated Wozinak Machine.

Built-in accessories

The Apple IIc had a built-in 5.25" floppy drive (140K) along the right side of the case--the first Apple II model to include such a feature. Along the left side of the case was a dial to control the volume of the internal speaker, along with a 1/8" monaural audio jack for headphones or an external speaker. A fold out carrying handle doubled as a way to prop up back end of the machine to provide the proper angle for keyboard typing. Finally a (12 volt) voltage convertor was provided for using an external battery, which is where an included external powersupply (dubbed a "brick on a rope" by users) was connected, and plugged into a standard wall socket.

Keyboard changes

The keyboard layout mirrored that of the Apple IIe, however the 'Reset' key had been moved above the 'ESC' key. Two toggle switches were also located in the same area: an "80/40" columns switch for (specially written) software to detect which text video mode to start up in, and a "Keyboard" switch to select between QWERTY and DVORAK layout. The keyboard itself was built-in to the front half of the case (much like a notebook computer) and had a rubber mat placed beneath the keycaps which acted as a liquid spill guard.

Expansion ports

In the rear of the machine were its expansion ports, mostly for providing access to its built-in cards. The standard DE9 joystick connector doubled as a mouse interface, compatible with the same mice used by the Lisa and early Macintosh computers. Two serial ports were provided primarily to support a printer or modem, a floppy port connector supported a single external 5.25 drive. A Video Expansion port provided rudimentary signals for add-on adapters but alone could not directly generate a video signal (Apple produced a LCD display and an RF-modulator for this port). A port connector tied into an internal 12 volt power convertor for attaching batteries; this is where the infamous "brick on a rope" external powersupply Apple provided plugged in. The same composite video port found on earlier Apple II models remained present, however gone were the cassette ports and internal DIP-16 game port.


Technical specifications

File:Apple IIc motherboard.jpg
Apple IIc motherboard, normally inaccessible in this closed system. Note the silver boxed voltage convertor on the left, and the long vertical row of chips on the right making up its 128K RAM

Microprocessor

  • 65C02 running at 1.023 MHz
  • 8-bit data bus

Memory

  • 128K RAM built-in
  • 32K ROM built-in (original, 16K ROM)
  • Expandable from 128K to 1 MB (original, only through non-conventional methods)

Video

  • 40 and 80 columns text, with 24 lines¹
  • Low-Resolution: 40x48 (16 colors)
  • High-Resolution: 280x192 (6 colors)*
  • Double-Low-Resolution: 80x48 (16 colors)
  • Double-High-Resolution: 560x192 (16 colors)*

*effectively 140x192 in color, due to pixel placement restrictions

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

Audio

  • Built-in speaker; 1-bit toggling
  • User adjustable volume (manual dial control)

Built-in storage

  • Slim-line internal 5.25 floppy drive
  • 140K, single-side

Internal connectors

  • Memory Expansion Card connector (34-pin)*

* Only available on ROM 3 motherboard and higher; original IIc: NONE

Specialized chip controllers

  • IWM (Integrated Wozinak Machine) for floppy drives
  • Dual 6551 ASIC chips for serial I/O

External connectors

  • Joystick/Mouse (DE-9)
  • Printer, serial-1 (DIN-5)
  • modem, serial-2 (DIN-5)
  • Video Expansion Port (D-15)
  • Floppy drive Smartport (D-19)
  • 12 Volt DC connector input (DIN-7, male)
  • NTSC composite video output (RCA connector)
  • Audio-out (1/8" mono phono jack)

Revisions

The Apple IIc was in production between April 1984 until August 1988, and during this time, did go through some small changes. These included the existence of 4 ROM revisions, two motherboards (including a bug fix for one), and a slight cosmetic change to the external appearence of the machine. Note the original IIc ROM is identified as ROM revision "255". These revisions are detailed below.

Serial port timing fix

The original Apple IIc motherboard (those manufactured between April and November 1984) derived the timing for its two serial ports through a 74LS161 TTL logic chip. It was later found that this method's timing was 3% slower than the minimum requirement and caused certain modems and printers, which operated at 1200 bits per second (baud) or faster, to not function with the Apple IIc. The solution was primarily to replace the TTL chip with an oscillator in the manufacturing process. It had no ill effect on serial devices that operated slower however (e.g. 300 baud modem). Apple dealers at the time would swap effected motherboards, free of charge, to users who could prove they had an incompatible serial device.

UniDisk 3.5 support (ROM revision '0')

This update, introduced November 1985, came in the form of a new ROM firmware, which doubled in size from 16K to 32K. The main new feature of this ROM was the ability to support Apple's "intelligent" UniDisk 3.5 (800K) floppy drive, in addition to an external 5.25. A new self-test diagnostic was provided for testing built-in RAM and other signs of logic faults. The Mini-Assembler, abscent since the days of the Apple II Plus, made a return, and new Monitor "Step" and "Trace" commands were added as well. Of interesting note, this ROM added rudementary support hooks for an external AppleTalk networking device that had yet to be developed, as noted by the "APPLETALK OFFLINE" message when attempting to boot virtual slot 7. The IIc had no built-in networking capabilities however, and the external device was never released. The upgrade consisted of a single chip swap, which Apple provided free only to persons who purchased a UniDisk 3.5 drive.

The Memory Expansion IIc (ROM revision '3')

Introduced in September 1986, along side the Apple IIGS, this model introduced a new motherboard, new keyboard and new color scheme. The original Apple IIc had no expansion options, however third party cards performed hardware tricks by removing the CPU and MMU chips and squeezing a special board into these sockets, which then used bank switching to expand RAM (much like the Apple IIe's auxiliary slot). The new motherboard added a 34-pin socket for directly plugging in memory cards, no longer requiring trickery, and could address up to 1 megabyte using Slinky-type memory cards. The onboard chip count had been reduced from 16 memory chips (64Kx1) to 4 (64Kx4). The new firmware removed any code for the cancelled AppleTalk networking device, replacing it with support for memory cards (which caused some shuffling: Memory now lived in virtual slot 4, the Mouse moved to slot 7; bumping out the future AppleTalk support). The keyboard removed the rubber anti-spill mat and offered generally more tactile and responsive keys that felt more "clicky". At the same time the color of the keyboard, floppy drive latch and powersupply cords changed from beige to light grey, to match the new Platinum color scheme of the Apple IIGS. The case remained snow white however. Generally only current purchasers of the Apple IIc received this new model, however owners of previous model IIc's were entitled to a free motherboard upgrade if they purchased one of Apple's IIc memory expansion boards (they did not receive the new keyboard or the cosmetic changes however).

The Memory Expansion IIc, fix (ROM revision '4')

In January 1988 a new ROM firmware update was issued, solely to address bug issues in the new memory expandable IIc. Changes included better detection of installed RAM chips, correction of a problem when using the serial modem port in terminal-mode, and finally a bug fix for keyboard buffering. The ROM upgrade was available free of charge only to owners of the memory expansion IIc. This was the final change to the Apple IIc until a new Apple II model, the Apple IIc Plus, replaced it.

International versions

Like the Apple IIe before it, the Apple IIc 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 IIc such as "á", "é", "ç", etc, or the British Pound "£" symbol on the UK IIc) while other times the layout and shape of keys greatly differed (e.g. European IIc). In order to access the local character set, the "Keyboard" switch above the keyboard (used for switching between QWERTY and DVORAK layouts on US models) was depressed, which would instantly switch video from the US character set to the local set. In some countries these localized IIc's also supported 50 Hz PAL video and the different 110/220 volt power of that region by means of a different external powersupply--made simplified since the IIc had an internal 12 volt power convertor. The internal versions also changed any English wording printed on the case, specifically the "keyboard" toggle switch, power and drive activity labels, with graphical icon symbols that could be universally understood.

Add-on accessories

The Apple Flat Panel Display LCD

At the time of the Apple IIc's release, Apple announced an optional black and white (1-bit) LCD display specifically designed for the machine. While it was welcomed as a means of making the IIc more portable, it did not integrate well as a portable display in that it didn't attach in a secure or permanent manner, and could not fold-over face down. Instead it balanced loosely atop the machine (fitting inside the vertical grooves) and connected by ribbon cable to a somewhat bulky rear port connector. Beyond this, its main shortcoming was it suffered from a very poor contrast and no backlighting, making it very difficult to view. The display itself had an odd aspect ratio as well, making images look vertically squished. The product did not sell very well due to its limitations and was discontinued not long after.

The C-Vue LCD

Another company produced a third party work-alike version of the Apple display called The C-Vue. It looked and functioned very much like Apple's product, and although reported as offering improvements in visual quality, suffered from the same poor readability due to a poor contrast and no backlighting (a strong external light source was required to see either screen). It mounted at the back end of the Apple IIc, whereas Apple's product sat directly in front of the keyboard, and had a much smaller port connector. A permanent docking station was mounted to the back of the Apple IIc, which allowed it to tilt, however it could not fold over the case. It too suffered from poor sales and like its Apple cousin, very few sold and considered extremely rare today.

External batteries

Some third party companies offered external rechargable battery packs for the Apple IIc (e.g. the Prairie Pack). Although they aided in making the Apple IIc a portable machine, they were typically bulky and heavy, and added more pieces that would have to be carried. Powering an Apple IIc off a car battery was possible through DC cigratte-lighter cable connectors.

'Clocks, Memory, Co-processors'

Many companies produced real-time clocks, memory expansion options and Z-80 coprocessor adds-on for the Apple IIc. Some products offered all three options on a single board. Some clocks could be added externally. Memory expansion on the original Apple IIc, which had no expansion whatsoever, got around this by using trickery in removing key chips and plugging specialized boards into their sockets.

'Hardrives'

Some companies produced hardisk that connected externally to the Apple IIc's floppy Smartport (e.g. ProAPP, Chinook, C-Drive). While providing true mass storage, they were relatively slow due to the nature of how the Smartport operated.

'Accelerators'

A product called the Zip Chip (and another called the Rocket Chip) replaced the 1 MHz microprocessor with a specialized one running at 4-10 MHz. It contained it's own memory RAM cache and logic, all self-contained in a tall chip that directly replaced the existing processor.

'Sound enhancements

Speech and music synthesis could be added through external devices that plugged into the serial ports. One such popular device was the Mockingboard-D, or Echo IIc.


See also

External links

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