Apple II Plus


Apple II Plus
Manufacturer Apple Computer
Introduced 1978
Discontinued 1982
Price US$1200
CPU MOS Technology 6502, 1 MHz
RAM 48 KB (up to 64 KB),
OS Apple DOS

The Apple II Plus was the second model of the Apple II series of personal computers produced by Apple Computer, Inc.

Contents

Features

It had a total of 48 KB 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.

The Apple II Plus 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 noticeably slower speed than Steve Wozniak's Integer BASIC) and became the standard BASIC dialect on the Apple.

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. Other programs used inverse text mode to represent text that would be lowercase when printed. 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" connected the Shift key 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. For this reason, most applications that could support lower-case letters could also use the ESC key as a substitute lowercase toggle if the "shift key mod" was not installed.

Apple II Europlus and J-Plus

After the success of the first Apple II in the United States, Apple expanded its market to include Europe and the Far East in 1978, with the Apple II Europlus (Europe) and the Apple II J-Plus (Japan). In these models, Apple made the necessary hardware, software and firmware changes in order to comply to standards outside of the US. The power supply was modified to accept the local voltage, and in the European model the video output signal was changed from color NTSC to monochrome PAL — an extra video card was needed for color PAL graphics, since the simple tricks Wozniak had used to generate a pseudo-NTSC signal with minimal hardware didn't carry over to the more complex PAL system. In the Japanese version of the international Apple, the keyboard layout was changed to allow for Katakana writing (full Kanji support was clearly beyond the capabilities of the machine), but in most other countries the international Apple was sold with an unmodified American keyboard; thus the German model still lacked the umlauts, for example. For the most part, the Apple II Europlus and J-Plus were identical to the Apple II Plus. Production of the Europlus ended in 1983.

Bell & Howell

The Apple II Plus was also sold by Bell & Howell specifically to educational markets under special license from Apple. It was identical to the beige consumer version sold by Apple except that it came in a black case, which could not be as easily opened, and a sepcial A/V package allowing it to be sold as audio/visual equipment. The FCC would not allow Apple to sell the unmodified II Plus directly to schools because it could be run without a top and therefore Apple used the well known scholastic A/V distributor to get around this regulation. Bell & Howell packaged the unit with optional fanny packs which offered various inputs and outputs for A/V equipment to easily interface with the II Plus, further reinforcing the illusion as an A/V product. [1] This was the only black computer Apple would manufacture until the Macintosh TV in 1993.

Timeline of Apple II Family models

See also: Timeline of Apple II Family

See also: Timeline of Apple Macintosh models and Timeline of Apple products

See also

References

External links


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