World Library  
Flag as Inappropriate
Email this Article

Macintosh II

Article Id: WHEBN0000177113
Reproduction Date:

Title: Macintosh II  
Author: World Heritage Encyclopedia
Language: English
Subject: History of Mac OS, Macintosh SE, System 6, NuBus, Macintosh IIvx
Collection: 68K MacIntosh Computers, A/Ux-Capable MacIntoshes, MacIntosh Case Designs, MacIntosh Desktops, MacIntosh II Series
Publisher: World Heritage Encyclopedia

Macintosh II

Macintosh II
Release date March 2, 1987 (1987-03-02)
Introductory price US $5500
Discontinued January 15, 1990 (1990-01-15)
Operating system 4.1-7.1.1 (Pro), 7.5-7.5.5 or with 68030 32-bit upgrade Mac OS 7.6.1
CPU Motorola 68020 @ 16 MHz
Memory 1 MB, expandable to 20 MB (68 MB via FDHD upgrade kit) (120 ns 30-pin SIMM)

The Apple Macintosh II is the first personal computer model of the Macintosh II series in the Apple Macintosh line and the first Macintosh to support a color display. A basic system with 20 MB drive and monitor cost about $5500, A complete color-capable system could cost as much as $10,000 once the cost of the color monitor, video card, hard disk, keyboard and RAM were added. This price placed it in competition with workstations from Silicon Graphics, Sun Microsystems and Hewlett-Packard.

The Macintosh II was designed by hardware engineers Michael Dhuey (computer) and Brian Berkeley (monitor) and industrial designer Hartmut Esslinger (case).


  • History 1
  • Features 2
  • Graphics card 3
  • See also 4
  • References 5
  • External links 6


Two common criticisms of the Macintosh from its introduction in 1984 were the closed architecture and lack of color; rumors of a color Macintosh began almost immediately,[1]

The Macintosh II project was begun by Dhuey and Berkeley during 1985 without the knowledge of Apple co-founder and Macintosh division head Steve Jobs, who opposed features like expansion slots and color, on the basis that the former complicated the user experience and the latter did not conform to WYSIWYG, since color printers were not common.[2] Initially referred to as "Little Big Mac", it was codenamed "Milwaukee" after Dhuey's hometown, and later went through a series of new names, including "Reno", "Uzi" and "Paris" (after Jean-Louis Gassee, Apple's then products manager, who protected the semi-clandestine project from cancellation).[3] After Jobs was fired from Apple in September 1985, the project could proceed openly.

Introduced in March 1987 and retailing for US $5,498,[4] the Macintosh II was the first "modular" Macintosh model, so called because it came in a horizontal desktop case like many IBM PC compatibles of the time. All previous Macintosh computers used an all-in-one design with a built-in black-and-white CRT.

The Macintosh II had drive bays for an internal hard disk (originally 20 MB or 40 MB) and an optional second floppy disk drive. It, along with the Macintosh SE, was the first Macintosh computer to use the Apple Desktop Bus (ADB) introduced with the Apple IIGS for keyboard and mouse interface.

The primary improvement in the Mac II was Color QuickDraw in ROM, a color version of the graphics language which was the heart of the machine. Among the many innovations in Color QuickDraw were an ability to handle any display size, any color depth, and multiple monitors. With its pioneering support for 32-bit color[5] (24 bit color depth and 8 bit alpha channel) Mac II was the first personal computer which could display true color photorealistic images without aftermarket upgrades. Because Color QuickDraw was included in the Mac II's ROM, earlier Macintoshes could not be upgraded to display color.


The Mac II featured a Motorola 68020 processor operating at 16 MHz teamed with a Motorola 68881 floating point unit. The machine shipped with a socket for an MMU, but the "Apple HMMU Chip" (VLSI VI475 chip) was installed that did not implement virtual memory (instead, it translated 24-bit addresses to 32-bit addresses for the Mac OS, which was not 32-bit clean until System 7). Standard memory was 1 megabyte, expandable to 68 MB, though not without the special FDHD upgrade kit; otherwise, 20 MB was the maximum.[6] RAM could be maxed out to 128 MB, however, if the ROMs were upgraded to those used in the IIx (or if MODE32 was used), as the Mac II's memory controller supported higher-density memory modules than did the stock ROM.[7][8] The Mac II had eight 30-pin SIMMs, and memory was installed in groups of four. A 5.25-inch 40 MB internal SCSI hard disk was optional, as was a second internal 800 kilobyte 3.5-inch floppy disk drive. Six NuBus slots were available for expansion (at least one of which had to be used for a graphics card, as the Mac II had no onboard graphics chipset). It is possible to connect as many as six displays to a Macintosh II by filling all of the NuBus slots with graphics cards. Another option for expansion included the Mac286, which included an Intel 80286 chip and could be used for MS-DOS emulation.

The original ROMs in the Macintosh II contained a bug which prevented the system from recognizing more than one megabyte of memory address space on a Nubus card. Every Macintosh II manufactured up until about November 1987 had this defect. This happened because Slot Manager was not 32-bit clean.[9] Apple offered a well publicized recall of the faulty ROMs and released a program to test whether a particular Macintosh II had the defect. As a result, it is rare to find a Macintosh II with the original ROMs.

The Macintosh II and Macintosh SE were the first Apple computers since the Apple I to be sold without a keyboard. Instead the customer was offered the choice of the new ADB Apple Keyboard or the Apple Extended Keyboard as a separate purchase. Dealers could bundle a third-party keyboard or attempt to upsell a customer to the more expensive (and higher-profit) Extended Keyboard.

Macintosh II motherboard

The Macintosh II was followed by a series of related models including the Macintosh IIx and Macintosh IIfx, all of which used the Motorola 68030 processor. It was possible to upgrade a Macintosh II to a Macintosh IIx or IIfx with a motherboard swap. The Macintosh II was the first Macintosh to have the Chimes of Death accompany the Sad Mac logo whenever a serious hardware error occurred.

The new extensions featured for the Macintosh II at the time were A/ROSE and Sound Manager.

Graphics card

The card was unaccelerated, but it had a 16.7 million color palette (true color).[10] It supported two resolutions, 512×384 and 640×480 (supporting Apple's fixed-resolution 12" and 13" color monitors respectively) and was available in two configurations, 4-bit and 8-bit. The 4-bit model supports 16 colors on a 640×480 display, 256 colors (8-bit video) on a 512×384 display, which means that VRAM was 256 KB. The 8-bit model supports 8-bit/256-color video on a 640×480 display, which means that VRAM was 512 KB in size. With an optional RAM upgrade (requires eight 120 ns DIP chips), the 4-bit version supports 640×480 in 8-bit color.[11]

See also


  1. ^ Bartimo, Jim (1985-02-25). "Macintosh: Success And Disappointment". InfoWorld. p. 30. Retrieved 27 January 2015. 
  2. ^ "The Color Convergence". 
  3. ^ Levy, Steven. Insanely Great: The Life and Times of Macintosh, the Computer That Changed Everything. New York: Viking, 1994; p. 229-231
  4. ^ Macintosh II and Macintosh SE announced
  5. ^ "The First Expandable Macs: Mac II and SE". 
  6. ^ Apple Announces 68030 Macintosh IIx With High Density Compatible Drive by John Cook and Carol Cochrane, Business Wire 09/19/88 (retrieved September 20, 2009)
  7. ^ MACINTOSH II ROM, RAM, FPU, & PMMU CONFIGURATIONS by gamba (retrieved September 20, 2009)
  8. ^ Series: The 24-bit ROM Blues by Adam C. Engst, Tidbits, April 22, 1991 (retrieved September 21, 2009)
  9. ^ InfoWorld Magazine, October 26, 1987, p.47
  10. ^
  11. ^

External links

  • Macintosh II on
  • Mac II profile on Low End Mac
  • Macintosh II technical specifications at
Preceded by
Macintosh II
March 2, 1987
Succeeded by
Macintosh IIx
Macintosh IIcx
This article was sourced from Creative Commons Attribution-ShareAlike License; additional terms may apply. World Heritage Encyclopedia content is assembled from numerous content providers, Open Access Publishing, and in compliance with The Fair Access to Science and Technology Research Act (FASTR), Wikimedia Foundation, Inc., Public Library of Science, The Encyclopedia of Life, Open Book Publishers (OBP), PubMed, U.S. National Library of Medicine, National Center for Biotechnology Information, U.S. National Library of Medicine, National Institutes of Health (NIH), U.S. Department of Health & Human Services, and, which sources content from all federal, state, local, tribal, and territorial government publication portals (.gov, .mil, .edu). Funding for and content contributors is made possible from the U.S. Congress, E-Government Act of 2002.
Crowd sourced content that is contributed to World Heritage Encyclopedia is peer reviewed and edited by our editorial staff to ensure quality scholarly research articles.
By using this site, you agree to the Terms of Use and Privacy Policy. World Heritage Encyclopedia™ is a registered trademark of the World Public Library Association, a non-profit organization.

Copyright © World Library Foundation. All rights reserved. eBooks from Project Gutenberg are sponsored by the World Library Foundation,
a 501c(4) Member's Support Non-Profit Organization, and is NOT affiliated with any governmental agency or department.