• CPU: MOS 6502A 2 MHz
• RAM: 128 KB (up to 512 KB)
• ROM: 16 KB
• Text Modes: 40 or 80 chars x 24 lines
• Graphic Modes: 40 x 40-48 (16 col), 280 x 160-192 (6 col), 560 x 160-192 (2 col)
• Colors: 16 maximum
• I/O Ports: Monitor, Internal Slots (4), RS-232, Floppy disk port
• Keyboard: Full stroke 74-key with numeric keypad
• Built In Media: 140KB 5.25” disk-drive
• OS: SOS
• Built In Language: Business BASIC

MESS emulation supports apple3 with four disk drives: two Slot 6 Disks, which become in MESS “slot6disk1” (s6d1) and “slot6disk2” (s6d2), and two floppy disk drives, which become “floppydisk3” (flop3) and “floppydisk4” (flop4).

In each drive you can load a disk image in one of the supported formats: .do, .dsk, .bin, .po, .nib.

This system requires full keyboard emulation to work correctly. At startup, full keyboard emulation mode is enabled by default. Whilst in full keyboard emulation mode, some key associated functionality may be disabled (like the ESC key for EXIT). The keyboard emulation mode is toggled using the “Scroll Lock” key (by default).

Original Keyboard: QWERTY full stroke 74-key with numeric keypad

ESCAPE   1!   2@   3#   4$   5%   6^   7&   8*   9(   0)    -_     =+      \|         7    8    9


    TAB     Q    W    E    R    T    Y    U    I    O    P     [{     ]}    `~        4    5    6


  CONTROL      A    S    D    F    G    H    J    K    L     ;:   '"     RETURN       1    2    3


   SHIFT          Z    X    C    V    B    N    M    ,<   .>    /?  SHIFT    UP          0      .

ALPHA   OPEN   CLOSED
LOCK    APPLE  APPLE                 SPACEBAR                  LEFT  RIGHT  DOWN      -    ENTER

The emulation of this system is Preliminary.

The Apple /// was designed to be a business machine. It was partly compatible with the Apple II (thanks to a few options in the operating system). It used a powerful memory management system and worked under SOS (Sophisticated Operating System) which was a great, device-independent, operating system. This OS was the “ancestor” of ProDOS (the “professional” Apple operating system) and some parts of this system were used later in the Lisa and Macintosh OSs.

Despite its unique features, the Apple /// had a lot of technical problems, namely, the horrible case design. It caused the internal temperature to get so hot that the motherboard would warp and some of the socketed chips would become unseated. To remedy this, Apple told people to literally pick up the computer several centimeters off the desk and drop it! It was a miserable flop in the marketplace.

The Apple /// was followed in december 1983 by the Apple /// plus which had an Apple IIe style keyboard and a new video interface. Four months later, it was discontinued.

(info from old-computers.com)

• Applefritter (Excellent site about all Apple models,clones,prototypes,etc...)
• Apple /// at vintage-computer.com
• Apple /// at old-computers.com