Apple II Plus

Apple II Plus (known also as Apple ][ +) is a computer from the Pre-Macintosh family of Apple Computers. This model was an updated version of the Apple II and came with 48K RAM, as well as a new auto-start ROM for easier start-up and screen editing. Altogether, except for improved graphics, disk-booting support in the ROM, and the removal of the 2k 6502 assembler/disassembler to make room for the floating point BASIC, the Apple II+ was otherwise identical to the original Apple II model.

Apple II Plus

Introduction: June 1979.


  • Processor: CPU: MOS Technology/SynerTek 6502. CPU Speed: 1 MHz. FPU: none. Bus Speed: 1 MHz. Register Width: 8-bit. Data Bus Width: 8-bit. Address Bus Width: 16-bit.
  • ROM: 12 kB.
  • Onboard RAM: 48 kB.
  • RAM slots: 1st expansion slot can be used.
  • Maximum RAM: 64 kB.
  • Expansion Slots: 8 proprietary slots.
  • Video Max Resolution: Six colors at 280 x 192, 4-bit color at 40 x 48.
  • Floppy Drive: optional.
  • Input/Output: Serial: optional expansion card.
  • Speaker: mono.
  • Dimensions: 4.24-inch Height x 15.25-inch Width x 17.75-inch Deep.
  • Weight: 11.5 lbs.

Price and Discontinuation

Retail price: $1195.

Terminated: December 1982, replaced by Apppe IIe. Apple ended the production of the Europlus in 1983.


  • According to many sources, all Apple II Plus machines came with a full 48k of memory already installed.  However, the personal experience of some users does not confirm this statement (see comment to the text). Besides the language card in Slot 0 added another 16k, but it had to be bank switched since the remaining CPU address space was occupied by the ROMs and I/O area. The extra RAM in the language card was thus 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. The language card was also required to use the UCSD Pascal and FORTRAN 77 compilers. These ran under the UCSD p-System operating system, which had its own disk format and emitted code for a “virtual machine” rather than the actual 6502 processor.
  • The Apple II Plus included the Applesoft BASIC programming language in ROM, the Microsoft-authored dialect of BASIC. This language supported floating-point arithmetic, and became the standard BASIC dialect on the Apple II series, though it ran at a noticeably slower speed than the Integer BASIC developed by Steve Wozniak.
  • Apple sold this model in Europe as the Apple II Europlus. It had ESC sequences for European letters. Apple also expanded its market to include Australia and the Far East, where it sold the model as the Apple II J-Plus in Japan. In all these models, Apple made the necessary hardware, software and firmware changes in order to comply to standards outside of the U.S. For example, the power supply was modified to accept the local voltage.
  • In the European and Australian models the Apple II plus could display in PAL system, that is the video output signal was changed from color NTSC to monochrome PAL – an extra video card was needed for color PAL graphics, since the tricks Wozniak had used to generate a pseudo-NTSC signal with minimal hardware did not 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, but full Kanji support was beyond the capabilities of the computer.
  • Curiously enough, in most other countries Apple sold its international version with an unmodified American keyboard; thus the German model still lacked the umlauts, for example. But for the most part, the Apple II Europlus and J-Plus were identical to the Apple II Plus.
  • Most game publishers did not include DOS on their floppy disks for Apple II Plus, since they needed the memory it occupied more than its capabilities; instead, they often wrote their own boot loaders and read-only file systems. This also served to discourage crackers from snooping around in the game’s copy-protection code, since the data on the disk was not in files. Some third-party manufacturers produced floppy drives that could write 40 tracks to most 5.25-inch disks, yielding 160 kB of storage per disk, but the format did not catch on widely, and no known commercial software was published on 40-track media. Most drives, even Disk IIs, could write 36 tracks; a two byte modification to DOS to format the extra track was common.
  • Bell & Howell repackaged the Apple II Plus in a black case and sold it to educational markets.
  • The first 1000 or so Apple IIs shipped with a 68-page mimeographed “Apple II Mini Manual” bound with brass paper fasteners. This was the basis for the Apple II Plus Reference Manual (a/k/a Red book). All existing customers who sent in their warranty cards were sent free copies of the Red Book. The Apple II Plus Reference Manual contained the complete schematic of the entire computer’s circuitry and a complete source listing of the “Monitor” ROM firmware that served as the machine’s BIOS. A revised spiral bound guide released several years later with updated information had to be purchased separately, and in the case of the Apple IIgs, the full technical documentation ran to several volumes.
  • Specialty peripherals kept the Apple II in use in industry and education environments for many years after Apple Computer stopped supporting the Apple II. Well into the 1990s every clean-room (the super-clean facility where spacecraft are prepared for flight) at the Kennedy Space Center used an Apple II to monitor the environment and air quality. Most planetariums used Apple IIs to control their projectors and other equipment.
  • In 1980, the Georgia Tech Research Institute developed a TEMPEST-approved version of the Apple II Plus for the U.S. Army. The system was used as a component in the earliest versions of the Microfix system, which was the first tactical system using video disk (Laserdisc) map technology providing zoom and scroll over map imagery coupled with a point database of intelligence data such as order of battle, airfields, roadways, and bridges.


  • Yes, selling an old computer online can be a great way of making some fast extra cash and saving money for the next model: Sell old electronics online now.

Apple II Plus Computer Inside (1979). Video uploaded by Cochise Timothy Taylor on February 14, 2015


This post currently has 3 responses

  • “All Apple II Plus machines came with a full 48k of memory already installed.”

    That does _not_ match my personal experience. My ][+ purchased in late 1980 had only 16k of RAM. I didn’t upgrade it to 48k until a couple of years later, when I finally got my Disk ][.

  • Thats right, I got my Apple II+ with 16k of Ram and did upgrade it to 48k with two 32k banks and added next to my 128k diskdrive an 192k memory card operating as pseudo-disk with CP/M (very fast) plus Visicalc an dBase II etc…
    Now I am looking for a new owner of my ‘stuff’

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