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| {{Infobox computer | | {{Infobox computer |
| | name = Macintosh II | | | name = Macintosh II |
| | image = [[File:MacintoshII.jpg|250px]] | | | image = [[File:MacintoshII.jpg|250px|frameless]] |
| | caption = Original Macintosh II | | | caption = Macintosh II |
| | manufacturer = Apple Computer, Inc. | | | manufacturer = Apple Computer, Inc. |
| | type = Personal computer | | | type = Desktop personal computer |
| | release date = March 1987 | | | release date = 2 March 1987 |
| | discontinued = January 1990 | | | discontinued = 15 January 1990 |
| | price = US\$5,498 (base configuration) | | | price = US$5,498 at introduction |
| | cpu = Motorola 68020 @ 15.6772 MHz (Apple's figure; usually quoted as 16 MHz) | | | cpu = Motorola 68020 at 15.6772 MHz |
| | fpu = Motorola 68881 | | | fpu = Motorola 68881 |
| | memory = 1 MB standard, expandable to 8 MB (Apple's figure) in eight 30-pin SIMM slots | | | memory = 1 MB, expandable to 8 MB (eight 30-pin SIMM slots) |
| | rom = 256 KB ROM | | | rom = 256 KB |
| | storage = Internal 800 KB 3.5″ floppy (1.4 MB upgrade optional); optional internal 40, 80 or 160 MB SCSI hard drive | | | storage = 800K floppy drive; optional second 800K drive; optional 1.4 MB upgrade; optional 40, 80 or 160 MB SCSI hard drive |
| | display = Supports external monitors via NuBus video card; resolution and color depth depend on installed card | | | display = None built in; NuBus video card required |
| | graphics = No onboard graphics; requires NuBus video card
| | | sound = Apple sound chip, 8-bit stereo at 44.1 kHz, four-voice wavetable synthesis |
| | sound = Apple custom sound chip: 8-bit stereo sampling at 44.1 kHz, four-voice wavetable synthesis; no input | | | ports = SCSI (DB-25), 2 × ADB, 2 × serial (mini DIN-8), stereo sound jack, 6 × NuBus |
| | ports = 1 × DB-25 SCSI; 2 × ADB; 2 × Mini-DIN-8 serial; audio out jack; 6 × NuBus slots | | | dimensions = 14.0 cm (5.5 in) H × 47.4 cm (18.7 in) W × 36.5 cm (14.4 in) D |
| | dimensions = 140 mm (5.5 in) H × 474 mm (18.7 in) W × 365 mm (14.4 in) D | | | weight = 10.9 kg (24 lb) without hard drive |
| | weight = 10.9 kg (24 lb), more with an internal hard drive | | | power = 220 W maximum excluding monitor; 100-240 V AC automatically configured, 48-62 Hz |
| | power = 220 W maximum, excluding the monitor; 100–240 VAC automatically configured, 48–62 Hz | | | os = System Software 2.0 (System 4.1) to System 7.5.5 |
| | os = System 4.1 (with Finder 5.5) – Mac OS 7.6.1 | |
| | predecessor = [[Macintosh Plus]]
| |
| | successor = [[Macintosh IIx]] | | | successor = [[Macintosh IIx]] |
| | codename = “Milwaukee” | | | codename = Milwaukee |
| | model = M5000 | | | model = M5000 |
| }} | | }} |
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| The '''Macintosh II''' is a personal computer designed, manufactured, and sold by Apple Computer from March 1987 to January 1990. As the first modular Macintosh computer, it marked a significant departure from the original all-in-one design philosophy established by the [[Macintosh 128K]] in 1984. The Macintosh II was Apple's first computer to support color graphics, expansion slots, and a separate monitor, representing a major evolution in the Macintosh product line and establishing the foundation for professional desktop computing at Apple. | | The '''Macintosh II''' is a desktop computer made by Apple Computer from March 1987 to January 1990. It was the first Macintosh with a separate monitor, expansion slots (six NuBus slots) and colour graphics, and the first to use the Motorola 68020.<ref name="wp">{{cite web |url=https://en.wikipedia.org/wiki/Macintosh_II |title=Macintosh II |publisher=Wikipedia |access-date=2026-09-30}} History, designers, codenames, launch at AppleWorld 1987, price, 1988 price rise, ROM NuBus recall; the article cites Steven Levy, "The Making of the Macintosh II", ''Macworld'', May 1987, pp. 55-63, and ''InfoWorld'', 26 October 1987, p. 47.</ref> Apple's service manual covers it together with the [[Macintosh IIx]] and [[Macintosh IIfx]], which use the same case design.<ref name="ss">Apple Computer, ''Macintosh II/IIx/IIfx'' Service Source (1995), [[:File:Macintosh ii.iix.iifx.pdf]]; see [[Macintosh II/IIx/IIfx Service Source]]. Page numbers are the PDF's: Specifications pp. 5-12; Symptom Charts pp. 15-31; Take Apart pp. 33-52; Upgrades pp. 54-67; Battery Verification, Replacement and Holder Board pp. 69-79; Exploded View p. 87.</ref> |
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| == Introduction == | | == History == |
| | The project was started in 1985 by hardware engineers Michael Dhuey and Brian Berkeley, without the approval of Steve Jobs, who opposed expansion slots and colour. It was first called "Little Big Mac" and then codenamed Milwaukee, after Dhuey's home town. After Jobs left Apple in September 1985 the project continued openly. The case was designed by Hartmut Esslinger.<ref name="wp" /> |
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| The Macintosh II represented a revolutionary shift in Apple's computer design philosophy when it was introduced on March 2, 1987. Unlike its predecessors, which featured integrated monitors and closed architectures, the Macintosh II embraced modularity and expandability, targeting professional users and businesses that required more powerful and flexible computing solutions. Priced at $5,498 for the base configuration (approximately $14,000 in 2023 dollars), it was positioned as a high-end workstation competing directly with systems from Sun Microsystems and Silicon Graphics.
| | Apple introduced the Macintosh II at AppleWorld in Los Angeles on 2 March 1987, alongside the [[Macintosh SE]], at US$5,498; small-volume shipments began two months later. In September 1988 Apple raised its price by about 20 per cent, shortly before the [[Macintosh IIx]] replaced it. The [[Macintosh IIcx]] arrived in early 1989, and Macintosh II sales ended in January 1990. Apple sold logic board upgrades that turned a Macintosh II into a IIx or IIfx.<ref name="wp" /><ref name="everymac">{{cite web |url=https://everymac.com/systems/apple/mac_ii/specs/mac_ii.html |title=Apple Macintosh II (Original) Specs |publisher=EveryMac |access-date=2026-09-30}} Introduced 2 March 1987, discontinued 15 January 1990; model M5000, Gestalt ID 6; two 3.6 V lithium batteries soldered to the board; supported system software 2.0 to 7.5.5.</ref> |
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| The development of the Macintosh II began in 1985 under the codename "Little Big Mac" and later "Milwaukee." The project was led by Michael Dhuey and Brian Berkeley, with significant input from Jean-Louis Gassée, who had recently joined Apple as head of product development. The team's goal was to create a Macintosh that could satisfy the demands of professional users while maintaining the ease of use that had become synonymous with the Macintosh brand.
| | == Specifications == |
| | | {| class="wikitable styled-table" |
| The Macintosh II's introduction marked several firsts for the Macintosh line: it was the first Mac to support color displays, the first to use the Motorola 68020 processor, the first to include [[NuBus]] expansion slots, and the first to separate the computer from the display. These innovations positioned the Macintosh II as a serious competitor in the professional workstation market and helped establish Apple's presence in desktop publishing, graphic design, and scientific computing.
| | |+'''Macintosh II specifications (Apple)'''<ref name="ss" /> |
| | | ! Item !! Specification |
| == Technical Specifications == | |
| | |
| The Macintosh II featured groundbreaking technical specifications that set new standards for personal computer performance and capability in 1987. At its core was the Motorola 68020 processor running at 16 MHz, accompanied by the Motorola 68881 floating-point unit (FPU), which provided hardware-accelerated mathematical calculations essential for scientific and engineering applications.
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| | |
| === Processor and Performance ===
| |
| | |
| {| class="wikitable"
| |
| |- | | |- |
| ! Component !! Specification !! Details
| | | Processor || Motorola 68020 at 15.6772 MHz; optional PMMU |
| |- | | |- |
| | CPU || Motorola 68020 || '''15.6772 MHz''' — Apple's own figure<ref name="ssmacintoshiiiixii" />; commonly rounded to 16 MHz | | | Coprocessor || Motorola 68881 |
| |- | | |- |
| | FPU || Motorola 68881 || Optional floating-point coprocessor | | | Addressing || 32-bit registers, 32-bit address bus, 32-bit data bus |
| |- | | |- |
| | Data Bus || 32-bit || Full 32-bit data path | | | RAM || 1 MB, expandable to 8 MB |
| |- | | |- |
| | Address Bus || 32-bit || Capable of addressing up to 4 GB of memory | | | ROM || 256K |
| |- | | |- |
| | Cache || 256 bytes on-chip || The 68020's own instruction cache. There is no board-level cache | | | Floppy drives || Internal 800K; optional second internal 800K; optional 1.4 MB upgrade |
| |- | | |- |
| | Coprocessor || Motorola '''68881''' || Apple's figure. The IIx and IIfx use the '''68882'''<ref name="ssmacintoshiiiixii" /> | | | Hard drive || Optional internal 40, 80 or 160 MB SCSI |
| |}
| |
| | |
| The 68020 processor represented a significant upgrade from the 68000 used in previous Macintosh models. With its full 32-bit architecture, the processor could handle larger amounts of data more efficiently and execute complex instructions faster than its predecessors. The optional 68881 FPU, while adding $500 to the system cost, provided dramatic performance improvements for applications requiring intensive mathematical calculations, such as CAD software and scientific modeling programs.
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| [[File:Apple Macintosh II motherboard.jpg|thumb|374x374px|Macintosh II Motherboard]]
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| | |
| === Memory Architecture ===
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| The Macintosh II introduced a sophisticated memory architecture that was revolutionary for personal computers of its era:
| |
| | |
| {| class="wikitable"
| |
| |- | | |- |
| ! Memory Type !! Specification !! Configuration Options
| | | SCSI || 5 MB/s; eight devices maximum (including the computer) |
| |- | | |- |
| | RAM Type || 120ns 30-pin SIMMs || Industry-standard modules | | | Other I/O || Two ADB ports; two RS-232/RS-422 serial ports (mini DIN-8); six NuBus slots with full 32-bit address and data |
| |- | | |- |
| | Base RAM || 1 MB || Minimum configuration | | | Sound || Apple custom sound chip: 8-bit stereo sampling at 44.1 kHz, four-voice wavetable synthesis; stereo output through the sound jack |
| |- | | |- |
| | Maximum RAM || '''8 MB''' || Apple's figure for the Macintosh II and IIx<ref name="ssmacintoshiiiixii" />. The '''68 MB''' previously given here is not achievable: eight 4 MB SIMMs come to 32 MB, not 68 MB, and 68 MB is the Centris/Quadra 610-class figure (4 MB soldered plus 64 MB of SIMMs) on a machine that has no soldered RAM. The Mac II's ROM is not 32-bit clean, which is the real ceiling | | | Power || 100-240 V AC, automatically configured; 48-62 Hz single phase; 220 W maximum, not including the monitor |
| |- | | |- |
| | Memory Slots || 8 SIMM slots || '''Two banks of four.''' A 32-bit data bus filled with ×8 SIMMs takes four modules per bank, so SIMMs are fitted and matched in fours, not pairs | | | Size and weight || 5.5 × 18.7 × 14.4 in (14.0 × 47.4 × 36.5 cm); 24 lb (10.9 kg), more with a hard drive |
| |-
| |
| | Memory Speed || 120 nanoseconds || Required for stable operation
| |
| |-
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| | ROM Size || 256 KB || Contained core system routines
| |
| |} | | |} |
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| The memory system is arranged as '''two banks of four SIMMs'''. A 32-bit data bus built from ×8 modules needs four per bank, so modules are matched and fitted in groups of four — not in pairs, as a previous version of this page said. Initially, 256 KB and 1 MB SIMMs were available, with 4 MB modules becoming available later. Apple's published maximum for this machine is '''8 MB'''<ref name="ssmacintoshiiiixii" />, which was still generous for 1987 when most personal computers were limited to 1–4 MB. | | There is no built-in video: at least one NuBus slot holds a video card.<ref name="wp" /> |
| | |
| | == Hardware == |
| | [[File:Apple Macintosh II motherboard.jpg|thumb|350px|Macintosh II logic board]] |
| | === Logic board and memory === |
| | The logic board has eight 30-pin SIMM sockets in two banks, A and B.<ref name="pina">Larry Pina, ''Macintosh II Repair and Upgrade Secrets'' (Brady Publishing, 1991, ISBN 0-13-929530-5), hosted as [[Macintosh II Repair and Upgrade Secrets]]. Chapter 4, pp. 102-109 (power-on problems, B1/B2, jump-starting, power supply 699-0389 and Table 4-3, real-time clock, fuses F1 and F2); chapter 6, p. 158 (banks A and B). A secondary source.</ref> Apple's symptom charts single out Apple-labelled SIMMs made by NEC with a date code of 9052 or earlier: they cause the error chord at start-up, a failure to boot, ghosting or lost video, hangs when the first application launches, and ID errors. Apple's cure is to replace them.<ref name="ss" /> |
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| | Logic board part numbers are 661-0528 (II), 661-0529 (IIx) and 661-0522 (IIfx). The power supply is 661-0375 for the II and IIx and 661-0542 for the IIfx.<ref name="ss" /> |
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| | === Memory management === |
| | The Macintosh II is supplied with Apple's HMMU chip in a socket. For virtual memory or A/UX it needs a Motorola 68851 PMMU: Apple's upgrade procedure prises out the HMMU and fits the PMMU in the same socket, matching the dot on the chip to the dot on the socket.<ref name="ss" /> The IIx and IIfx have the PMMU built into their 68030. |
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| | === ROM and the 1.4 MB drive upgrade === |
| | Macintosh II ROMs made until about November 1987 could not recognise more than 1 MB of address space on a NuBus card, and Apple recalled them.<ref name="wp" /> |
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| | The 1.4 MB floppy drive upgrade replaces all four ROM chips with 342-0639 (HI, at C13), 342-0640 (MED HI, C12), 342-0641 (MED LO, E13) and 342-0642 (LO, E12), and replaces the IWM chip with a SWIM. The drive needs system software 6.0.2 or later; with older software the Macintosh II treats it as an 800K drive. By the time of Apple's 1995 manual the kit was no longer available, and Apple's route to a SuperDrive was a IIx or IIfx logic board.<ref name="ss" /> |
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| === Expansion Architecture === | | === Batteries === |
| | Two ½AA lithium cells on the logic board keep the clock and parameter RAM (B1) and supply the power-on circuit (B2).<ref name="pina" /> Apple's instruction is to replace a cell that reads below 3.2 V on the 10 V DC range.<ref name="ss" /> On the original Macintosh II the cells are 3 V Varta units with pigtail leads soldered to the board; later boards have 3.6 V Tadiran TL-5112 cells in snap-in holders.<ref name="pina" /> Before fitting new cells to a board with soldered batteries, Apple fits a battery holder board: cut the old leads, desolder the four connections with an iron of 50 W or less without forcing them, and solder in the holder with its positive side in the holes marked positive.<ref name="ss" /> |
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| One of the Macintosh II's most significant innovations was its expansion slot architecture:
| | If the computer will not start from either the keyboard or the rear power switch, the usual cause is a flat B2. Pina reads good cells at 3.2-3.85 V, weak at 2.3-3.1 V and dead below 2.3 V, and says to change both cells together.<ref name="pina" /> A leaking cell damages the logic board. Lithium residue is neutralised with bicarbonate of soda, not vinegar; see [[Battery Explosion, Capacitor or Corrosion Damage]]. |
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| {| class="wikitable" | | === Power supply === |
| | Apple rates the supply at 220 W maximum, excluding the monitor, with automatic 100-240 V input.<ref name="ss" /> Pina gives the part as 699-0389, made by Astec or Sony and rated 156 W peak, and lists the voltages he measured on its connector:<ref name="pina" /> |
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| | {| class="wikitable styled-table" style="width:70%;" |
| | |+'''Power supply connector (Pina, Table 4-3)''' |
| | ! Pin !! Signal !! Measured range |
| |- | | |- |
| ! Feature !! Specification !! Purpose
| | | 1 || +12 V || 11.50-12.80 V |
| |- | | |- |
| | Expansion Bus || NuBus || 32-bit expansion bus | | | 2-6 || +5 V || 4.90-5.20 V |
| |- | | |- |
| | Number of Slots || 6 slots || All slots are full-length | | | 7-12 || Ground || - |
| |- | | |- |
| | Bus Speed || 10 MHz || Synchronous operation | | | 13 || No connection || - |
| |- | | |- |
| | Data Transfer || 40 MB/second || Theoretical maximum | | | 14 || −12 V || −13.40 to −10.80 V |
| |- | | |- |
| | Slot Power || Not published || Apple's Macintosh II Specifications chapter gives no per-slot power budget. A "25 watts per slot" figure was previously given here and could not be sourced | | | 15 || /PFW (power fail warning) || - |
| |-
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| | Auto-configuration || Yes || Plug-and-play capability
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| |} | | |} |
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| The [[NuBus]] expansion system was licensed from Texas Instruments and provided true plug-and-play functionality years before it became common in the PC world. Each slot could automatically configure inserted cards without the need for DIP switches or jumpers, making system expansion remarkably simple for users.
| | Apple publishes no rail tolerances and no voltage adjustment for the Macintosh II. The supply is started by the logic board: for bench testing, Pina powers it with mains connected and a 3 V source from two AA cells touched to pin 15, the same method he uses to start a machine with a dead B2.<ref name="pina" /> Apple's symptom chart notes that the thermal protection circuit can shut the system down if the vents on the sides and top are blocked, and that it recovers after 30-40 minutes.<ref name="ss" /> |
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| === Storage Options === | | === Fuses === |
| | Pina identifies two 1 A subminiature fast-acting fuses on the original Macintosh II logic board. F1, next to the internal hard drive connectors, is the likely fault when no external SCSI device is recognised; F2, behind the ADB connectors, when no ADB device works. A good fuse reads close to 0 Ω.<ref name="pina" /> |
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| The Macintosh II offered various storage configurations:
| | == Troubleshooting == |
| | Apple's symptom charts for the II, IIx and IIfx cover the error chord, power, video, floppy drives, hard drives and peripherals.<ref name="ss" /> Selected entries: |
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| {| class="wikitable" | | {| class="wikitable styled-table" style="width:100%; text-align:left;" |
| | |+'''From Apple's symptom charts''' |
| | ! Symptom !! Apple's cures, in order |
| |- | | |- |
| ! Storage Type !! Capacity !! Interface !! Notes
| | | Error chord at start-up || SIMM verification; replace NEC SIMMs dated 9052 or earlier; logic board |
| |- | | |- |
| | Internal Hard Drive || Optional 40, 80 or 160 MB || SCSI || Apple's figures<ref name="ssmacintoshiiiixii" /> | | | No power: black screen, fan off, LED off || Cables; monitor on its own wall socket; power cord; check batteries; power supply; logic board |
| |- | | |- |
| | Floppy Drive || 800 KB internal; optional second internal 800 KB drive; optional 1.4 MB upgrade || Internal || Apple's figures<ref name="ssmacintoshiiiixii" /> | | | Clicking, chirping or thumping || Remove extra NuBus cards; power supply; logic board |
| |- | | |- |
| | SCSI || '''Eight device maximum''', 5 MB/sec transfer rate || SCSI-1 || Apple's figures<ref name="ssmacintoshiiiixii" /> | | | Shuts down intermittently || Clear the vents and wait 30-40 minutes; power cord; batteries; power supply; logic board |
| |- | | |- |
| | SCSI Controller || NCR 5380 || Integrated || Supported SCSI-1 standard | | | Black screen, fan and LED on, drives working || Monitor brightness; try the monitor on another Mac; video cable; move the video card to another slot; video card; SIMMs; logic board; power supply |
| |}
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| == Key Features ==
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| The Macintosh II introduced numerous features that would become standard in professional computers and established paradigms that influenced computer design for years to come.
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| === Color Graphics Capabilities ===
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| The Macintosh II's color graphics system represented a quantum leap from the monochrome displays of earlier Macintosh computers. The system's graphics capabilities were provided through expansion cards, allowing users to choose the level of graphics performance that matched their needs and budget:
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| {| class="wikitable"
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| |-
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| ! Graphics Card !! Resolution !! Colors !! Video RAM !! Price
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| |- | | |- |
| | Apple High-Resolution Video Card || 640×480 || 256 from 16.7 million || 256 KB || $599 | | | Internal hard drive dead, LED off, no spin || Remove the data cable; power cable; check +5 V and +12 V at the drive; drive; logic board |
| |- | | |- |
| | Apple Two-Page Display Card || 1152×870 || Monochrome || 256 KB || $799 | | | Works with internal or external SCSI device, not both || External device must not be ID 0 (internal drive) or 7 (computer); check termination; terminator; the external device |
| |- | | |- |
| | Third-party cards || Various || Up to 24-bit color || 1-8 MB || $500-$3000 | | | Will not eject a disk || Hold the mouse button down while switching on; drive |
| |} | | |} |
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| The standard Apple High-Resolution Video Card supported 8-bit color depth, displaying 256 colors simultaneously from a palette of 16.7 million colors. This capability made the Macintosh II ideal for graphic design, desktop publishing, and multimedia applications. The system's open architecture allowed third-party manufacturers to develop more advanced graphics cards, with some supporting true 24-bit color and higher resolutions. | | The meaning of the start-up tones and Sad Mac codes is on [[Sad Mac Error Codes]]. |
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| === Audio System ===
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| The Macintosh II featured an advanced audio system that set new standards for personal computer sound:
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| * '''Apple Sound Chip (ASC):''' Custom 4-voice stereo sound synthesizer
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| * '''Sample Rate:''' 22.254 kHz standard, up to 44.1 kHz supported
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| * '''Audio Output:''' Stereo mini-jack connector
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| * '''Sound Input:''' Supported through expansion cards
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| * '''MIDI Support:''' Available through serial ports or expansion cards
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| The ASC provided four independent sound channels with stereo panning capabilities, allowing for complex sound synthesis and playback. This made the Macintosh II popular among musicians and audio professionals, particularly when combined with MIDI interfaces and professional audio software.
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| === Modular Design Philosophy ===
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| The Macintosh II's modular design represented a fundamental shift in Apple's approach to computer architecture:
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| '''Separate Display:''' Unlike previous Macintosh models, the II required a separate monitor, allowing users to choose displays that matched their specific needs. Apple offered several monitor options, from compact 12-inch displays to large 19-inch models.
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| '''Expandable Architecture:''' The six NuBus slots allowed users to add capabilities as needed:
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| * Graphics accelerators for improved display performance
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| * Network interface cards for Ethernet connectivity
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| * Video capture cards for multimedia production
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| * Specialized cards for scientific and industrial applications
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| * Additional serial and parallel ports for peripherals
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| '''Upgradeable Components:''' Nearly every major component could be upgraded:
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| * RAM could be expanded from 1 MB to 68 MB
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| * The processor could be upgraded to faster models
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| * Storage could be expanded internally and externally
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| * Graphics capabilities could be enhanced with new cards
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| === Operating System and Software ===
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| The Macintosh II shipped with System 4.1, which included support for color graphics and the new hardware features. The operating system evolved significantly during the computer's lifetime:
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| == Processor & Memory ==
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| === Motorola 68020 Processor ===
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| [[File:XC68020 top p1160084.jpg|thumb|245x245px|Motorola 68020]]
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| The Macintosh II was powered by the Motorola 68020 microprocessor, marking a significant advancement from the Motorola 68000 used in earlier Macintosh models. The 68020 operated at a clock speed of 15.6672 MHz, providing substantially improved performance over its predecessors.<ref>{{cite book |last=Pogue |first=David |title=Macworld Mac Secrets |year=1993 |publisher=IDG Books |isbn=1-56884-025-X |pages=654-655}}</ref>
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| The 68020 processor featured a full 32-bit architecture, with 32-bit data paths and 32-bit address buses, enabling the system to directly address up to 4 gigabytes of memory—though practical limitations of the era restricted actual memory capacity. The processor incorporated an on-chip instruction cache of 256 bytes, which significantly improved instruction fetch performance compared to the cacheless 68000.<ref>{{cite journal |title=Motorola's 68020 32-bit microprocessor |journal=IEEE Micro |volume=4 |issue=4 |year=1984 |pages=101-103}}</ref>
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| One of the most notable features of the 68020 was its support for virtual memory through an optional Motorola 68851 Paged Memory Management Unit (PMMU). While the base Macintosh II did not include the PMMU as standard equipment, it could be added via a dedicated socket on the motherboard, enabling advanced memory management features and compatibility with [[A/UX]], Apple's Unix operating system.<ref>{{cite book |last=Somerson |first=Paul |title=PC Magazine Guide to the Macintosh Family |year=1990 |publisher=Ziff-Davis Press |pages=234-236}}</ref>
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| === Floating-Point Coprocessor ===
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| [[File:Motorola 68881.jpg|thumb|216x216px|Motorola 68881]]
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| The Macintosh II included a socket for the Motorola 68881 floating-point unit (FPU), which operated at the same 15.6672 MHz clock speed as the main processor. The 68881 provided hardware acceleration for floating-point mathematical operations, crucial for scientific computing, 3D graphics, and engineering applications. The FPU implemented the IEEE 754 standard for floating-point arithmetic and supported single-precision (32-bit) and double-precision (64-bit) operations, as well as extended-precision (80-bit) calculations.<ref>{{cite manual |title=MC68881/MC68882 Floating-Point Coprocessor User's Manual |publisher=Motorola |year=1987 |id=MC68881UM/AD}}</ref>
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| === Memory Architecture ===
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| The Macintosh II featured a sophisticated memory subsystem that represented a major departure from earlier Macintosh designs. The system utilized 30-pin SIMM (Single In-line Memory Module) slots, with eight slots available for memory expansion. The memory controller supported both 256 KB and 1 MB SIMMs, though these could not be mixed within the same bank.<ref>{{cite book |last=Kobler |first=Randy |title=The Macintosh II Repair and Upgrade Secrets |year=1990 |publisher=Hayden Books |isbn=0-672-48452-8 |pages=145-167}}</ref>
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| Memory was organized in two banks of four SIMMs each, labeled Bank A and Bank B. The system required that SIMMs be installed in complete banks of four modules, and both banks had to contain the same capacity SIMMs. This configuration allowed for memory capacities of:
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| * 1 MB (four 256 KB SIMMs in Bank A)
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| * 2 MB (eight 256 KB SIMMs in both banks)
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| * 4 MB (four 1 MB SIMMs in Bank A)
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| * 8 MB (eight 1 MB SIMMs in both banks)
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| Later, with the introduction of 4 MB SIMMs, the maximum memory capacity could be expanded to 68 MB using special configurations, though this required specific ROM versions and was not officially supported by Apple.<ref>{{cite web |url=http://www.lowendmac.com/ii/macintosh-ii.html |title=Macintosh II: The First Modular Mac |publisher=Low End Mac |accessdate=2023-10-15}}</ref>
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| === Memory Performance ===
| |
| The memory subsystem operated with zero wait states at the standard clock speed, providing efficient memory access. The 32-bit data bus allowed the processor to fetch 32 bits of data in a single memory cycle, doubling the efficiency compared to the 16-bit data bus of the 68000. Memory refresh was handled automatically by dedicated circuitry, ensuring data integrity without processor intervention.<ref>{{cite manual |title=Macintosh II Developer Note |publisher=Apple Computer |year=1987 |id=030-3098-A}}</ref>
| |
| | |
| == Storage Systems ==
| |
| [[File:Quantum ProDrive LPS.png|thumb|292x292px|Quantum ProDrive]]
| |
| | |
| === Internal Hard Drive Support ===
| |
| The Macintosh II was the first Macintosh to include an internal hard drive as standard equipment, typically shipping with a 40 MB SCSI hard drive. The internal drive bay could accommodate a single 3.5-inch half-height hard drive, with power and data connections provided directly from the motherboard. The internal SCSI bus supported synchronous and asynchronous data transfers, with a maximum theoretical transfer rate of 5 MB/second, though actual performance was typically lower due to drive limitations.<ref>{{cite book |last=Engst |first=Adam |title=Internet Starter Kit for Macintosh |year=1993 |publisher=Hayden Books |pages=45-47}}</ref>
| |
| | |
| Popular internal hard drive options included:
| |
| * Apple HD SC (20, 40, or 80 MB capacities)
| |
| * Quantum ProDrive series
| |
| * Seagate ST-225 and ST-251 series
| |
| * Maxtor XT series
| |
| | |
| === Floppy Disk System ===
| |
| The Macintosh II incorporated a single 3.5-inch floppy disk drive using Apple's [[SuperDrive]] technology, capable of reading and writing 800 KB double-sided disks. The drive utilized the [[Integrated Woz Machine]] (IWM) controller chip, providing compatibility with 400 KB single-sided disks from earlier Macintosh systems. In 1988, Apple introduced the [[FDHD]] (Floppy Disk High Density) SuperDrive, which added support for 1.44 MB high-density disks while maintaining backward compatibility.<ref>{{cite journal |title=Apple's SuperDrive: A Technical Overview |journal=MacTech |volume=4 |issue=3 |year=1988 |pages=23-29}}</ref>
| |
| | |
| === SCSI Implementation ===
| |
| The Macintosh II featured a sophisticated SCSI implementation based on the NCR 5380 SCSI controller chip. The SCSI bus supported up to seven devices in addition to the Mac itself (which occupied SCSI ID 7), with both internal and external connections available. The external SCSI port used a DB-25 connector, which became standard across the Macintosh line.<ref>{{cite book |last=Pilgrim |first=Aubrey |title=Macintosh Hard Disk Management |year=1988 |publisher=Sybex |isbn=0-89588-508-8 |pages=78-92}}</ref>
| |
| | |
| Key features of the SCSI implementation included:
| |
| * Support for SCSI-1 standard
| |
| * 8-bit parallel data transfers
| |
| * Maximum cable length of 6 meters
| |
| * Automatic termination power
| |
| * Support for disconnect/reconnect operations
| |
| | |
| === External Storage Options ===
| |
| The robust SCSI implementation enabled connection of various external storage devices:
| |
| | |
| '''External Hard Drives''': Popular manufacturers included La Cie, FWB, MicroNet, and Jasmine, offering capacities ranging from 20 MB to over 1 GB by the early 1990s. These drives often included additional features such as backup software, disk utilities, and sometimes additional SCSI ports for daisy-chaining.
| |
| | |
| '''Removable Media Drives''': The Macintosh II supported various removable media systems:
| |
| * SyQuest removable cartridge drives (44 MB and 88 MB)
| |
| * Bernoulli Box drives from Iomega
| |
| * Magneto-optical drives
| |
| * Tape backup systems including QIC and DAT formats<ref>{{cite magazine |title=Removable Storage Roundup |magazine=MacUser |date=June 1989 |pages=156-178}}</ref>
| |
| | |
| == Expansion & Connectivity ==
| |
| | |
| === NuBus Architecture ===
| |
| [[File:Nubus-ppc950.jpg|thumb|NuBus Connector]]
| |
| The Macintosh II introduced [[NuBus]] as the expansion bus architecture for the Macintosh platform, providing six expansion slots for add-in cards. NuBus was originally developed at MIT and refined by Texas Instruments, offering a 32-bit multiplexed address/data bus operating at 10 MHz. This provided a theoretical maximum transfer rate of 40 MB/second, though practical throughput was typically lower.<ref>{{cite conference |title=NuBus: A Simple, Elegant, High-Performance Bus |conference=IEEE International Conference on Computer Design |year=1983 |pages=393-396}}</ref>
| |
| | |
| Key features of the NuBus implementation included:
| |
| * Automatic configuration with no DIP switches or jumpers
| |
| * Geographical addressing (each slot had a unique address range)
| |
| * Multi-master capability allowing cards to initiate transfers
| |
| * Fair arbitration ensuring equal access to the bus
| |
| * Support for block transfers and burst modes
| |
| | |
| === Expansion Card Categories ===
| |
| The NuBus slots accommodated various types of expansion cards:
| |
| | |
| '''Video Cards''': The Macintosh II required a video card for display output, as it had no built-in video circuitry. Popular options included:
| |
| * Apple High-Resolution Video Card (640×480, 8-bit color)
| |
| * Apple Two-Page Monochrome Card (1152×870)
| |
| * SuperMac Spectrum series
| |
| * RasterOps ColorBoard series
| |
| * Radius DirectColor/GX cards
| |
| | |
| == Operating System ==
| |
| | |
| The Macintosh II was designed from the ground up to run [[System Software 4.1]], marking a significant departure from previous Macintosh models. This operating system version was specifically engineered to support the II's revolutionary 32-bit architecture and color graphics capabilities, features that were unprecedented in the Macintosh line.
| |
| | |
| === System Software Evolution ===
| |
| | |
| The Macintosh II initially shipped with System Software 4.1 and Finder 5.5, which introduced crucial features for managing the computer's expanded capabilities. This version included support for Color QuickDraw, allowing applications to display up to 256 colors simultaneously from a palette of 16.7 million colors when equipped with the appropriate video card.<ref>Pogue, David. ''Macworld Mac Secrets''. IDG Books, 1993.</ref> The operating system also introduced improved [[MultiFinder]] support, enabling users to run multiple applications simultaneously—a feature that was essential for professional workflows.
| |
| | |
| As the platform matured, the Macintosh II became compatible with subsequent system software releases. [[System 6]], released in 1988, brought significant stability improvements and better memory management. This version introduced the 32-bit clean concept, preparing applications for future systems that would fully utilize the 68020 processor's 32-bit addressing capabilities. System 6.0.x versions became the most popular choice for Macintosh II users, offering an optimal balance of features and performance.<ref>Deutschman, Alan. ''The Second Coming of Steve Jobs''. Broadway Books, 2001.</ref>
| |
| | |
| The Macintosh II maintained compatibility through [[System 7.5.5]], released in 1996, though later versions required increasing amounts of RAM and offered diminishing returns in performance on the original hardware. System 7 introduced virtual memory, file sharing, and TrueType fonts, dramatically expanding the computer's capabilities for professional users.
| |
| | |
| === Memory Management ===
| |
| | |
| The operating system's memory management on the Macintosh II represented a significant advancement. While earlier Macintosh systems were limited to 24-bit addressing (accessing up to 16 MB of RAM), the Macintosh II's system software could theoretically support 32-bit addressing, allowing access to up to 4 GB of RAM. However, early versions maintained 24-bit compatibility mode for older applications, limiting practical memory usage to 8 MB under System 6.<ref>Apple Computer. ''Inside Macintosh Volume V''. Addison-Wesley, 1988.</ref>
| |
| | |
| The Memory Manager in the Macintosh II's operating system introduced new APIs for handling larger memory allocations and improved heap management. Applications could request temporary memory allocations, and the system provided better protection against memory fragmentation—a common problem in earlier Macintosh systems.
| |
| | |
| === File System Capabilities ===
| |
| | |
| The Macintosh II's operating system supported the Hierarchical File System (HFS), which had been introduced with the Macintosh Plus. However, the II's implementation included optimizations for handling larger hard drives, which were becoming increasingly common. The system software could manage volumes up to 2 GB in size, though most users operated with drives between 40 MB and 160 MB.<ref>Moritz, Michael. ''The Little Kingdom''. The Overlook Press, 1984.</ref>
| |
| | |
| == Bundled Software ==
| |
| | |
| The software bundle included with the Macintosh II was deliberately minimal, reflecting Apple's positioning of the machine as a professional workstation where users would select their own specialized applications. However, the included software provided essential functionality and demonstrated the system's capabilities.
| |
| | |
| === System Utilities ===
| |
| | |
| Every Macintosh II shipped with a comprehensive suite of system utilities. The [[Apple HD SC]] Setup utility allowed users to format and partition hard drives, supporting both Apple and third-party SCSI drives. This was crucial as the Macintosh II was one of the first Macintosh models to ship without a built-in floppy drive as the primary storage device.<ref>Kahney, Leander. ''The Cult of Mac''. No Starch Press, 2004.</ref>
| |
| | |
| The Font/DA Mover utility enabled users to install fonts and desk accessories into their System file. This tool was essential for managing the system's resources, as fonts and desk accessories were stored directly in the System file rather than in separate folders. The Macintosh II's color capabilities made font management particularly important for desktop publishing professionals.
| |
| | |
| === HyperCard ===
| |
| | |
| Beginning in late 1987, Apple included [[HyperCard]] with every Macintosh II sold. Created by Bill Atkinson, HyperCard was a revolutionary software tool that combined database, programming, and multimedia capabilities. It allowed users to create "stacks" of linked cards containing text, graphics, and interactive elements.<ref>Goodman, Danny. ''The Complete HyperCard Handbook''. Bantam Books, 1987.</ref>
| |
| | |
| HyperCard on the Macintosh II could take full advantage of the system's color capabilities, though the initial version was primarily designed for black-and-white displays. Users could create educational software, databases, presentations, and even simple games without traditional programming knowledge. The inclusion of HyperCard demonstrated Apple's vision of the Macintosh II as not just a computer, but a platform for creative expression.
| |
| | |
| === TeachText ===
| |
| | |
| TeachText, a simple text editor, was included as the default application for reading README files and basic text editing. While rudimentary compared to commercial word processors, TeachText served an important role in the Macintosh II ecosystem. It could handle SimpleText format files and provided basic styling capabilities including font selection, size adjustment, and style modifications.<ref>Williams, Gregg. "The Apple Macintosh Computer". ''Byte'', February 1984.</ref>
| |
| | |
| === Apple File Exchange ===
| |
| | |
| The [[Apple File Exchange]] utility was particularly important for the Macintosh II's target market of business professionals. This software enabled file transfers between Macintosh disks and DOS-formatted disks, facilitating data exchange with the PC-dominated business world. The utility could perform basic file format translations, converting between common text and data formats.
| |
| | |
| == Development History ==
| |
| | |
| The Macintosh II represented a fundamental shift in Apple Computer's product philosophy and marked the company's first serious attempt to penetrate the business and professional workstation markets. Development of the Macintosh II began in 1985 under the codename "Little Big Mac" and later "Milwaukee," representing a radical departure from the closed-system architecture that had defined previous Macintosh computers.
| |
| | |
| === Early Development (1985-1986) ===
| |
| | |
| The project emerged from internal tensions at Apple regarding the future direction of the Macintosh platform. While Steve Jobs had championed the original Macintosh's closed architecture and compact all-in-one design, a faction within Apple's engineering team, led by hardware engineer Michael Dhuey and project manager Brian Berkeley, advocated for a more expandable, modular system that could compete with IBM-compatible machines and high-end workstations from companies like Sun Microsystems.
| |
| | |
| Following Jobs' departure from Apple in September 1985, CEO John Sculley and head of engineering Jean-Louis Gassée greenlit the development of an open-architecture Macintosh. Gassée, who had previously worked at Hewlett-Packard, understood the importance of expandability in the business market and became the project's primary champion within Apple's executive team.
| |
| | |
| The development team faced numerous technical challenges, including:
| |
| * Implementing color graphics while maintaining compatibility with existing Macintosh software
| |
| * Designing a modular architecture that could accommodate third-party expansion cards
| |
| * Creating a system powerful enough to run complex professional applications
| |
| * Developing new ROM routines to support color QuickDraw and slot management
| |
| | |
| === Technical Innovations ===
| |
| | |
| The Macintosh II introduced several groundbreaking features that would define Apple's professional computers for years to come. The system utilized the Motorola 68020 processor running at 16 MHz, a significant upgrade from the 68000 used in previous Macintosh models. This processor, combined with an optional 68881 floating-point coprocessor, provided the computational power necessary for demanding applications like computer-aided design (CAD) and scientific visualization.
| |
| | |
| Perhaps the most revolutionary aspect was the implementation of NuBus, a 32-bit expansion bus technology originally developed at MIT. Apple's adoption of NuBus, led by engineers Rich Page and Bob Bailey, provided a clean, processor-independent expansion architecture that allowed for up to six expansion cards. This decision proved crucial for the machine's success in professional markets, enabling support for specialized video cards, network interfaces, and accelerator boards.
| |
| | |
| The development of Color QuickDraw, spearheaded by Andy Hertzfeld and Bill Atkinson, represented another major technical achievement. This extension of the original QuickDraw graphics routines enabled the Macintosh II to display up to 256 colors simultaneously from a palette of 16.7 million, while maintaining backward compatibility with existing monochrome applications.
| |
| | |
| === Final Development Phase ===
| |
| | |
| By late 1986, the Macintosh II had evolved into a sophisticated workstation-class computer. The final design featured a horizontal desktop case with easy access to internal components, a dramatic departure from the sealed-box approach of earlier Macintoshes. The development team, now expanded to include dozens of engineers and programmers, worked intensively to ensure the system's stability and compatibility.
| |
| | |
| Beta testing began in December 1986 with select developers and corporate customers. Feedback from these early users led to several last-minute refinements, including improvements to the ROM code and adjustments to the power supply design. The machine was officially announced on March 2, 1987, alongside the compact Macintosh SE, representing Apple's new two-pronged approach to the personal computer market.
| |
| | |
| == Market Reception ==
| |
| | |
| === Initial Launch and Pricing ===
| |
| | |
| The Macintosh II launched with a base price of $3,898 for a configuration without monitor, keyboard, or hard drive. A typical system with a 13-inch color monitor, keyboard, and 40MB hard drive cost approximately $7,000, positioning it firmly in the professional workstation category. Despite the high price point, initial demand exceeded Apple's production capacity, with waiting lists extending several months at many dealers.
| |
| | |
| The computer press received the Macintosh II enthusiastically. InfoWorld called it "the Mac that should have been," praising its expandability and color capabilities. BYTE magazine's review highlighted the system's impressive performance, noting that it outperformed many dedicated workstations costing significantly more. MacUser magazine awarded it their Editor's Choice Award for 1987, citing its potential to transform Apple's position in business markets.
| |
| | |
| === Business Market Penetration ===
| |
| | |
| The Macintosh II found immediate success in several key vertical markets:
| |
| | |
| * '''Desktop Publishing''': Publishers and design firms rapidly adopted the Macintosh II for its superior color capabilities and processing power. Major publications including USA Today and Time magazine integrated Macintosh II systems into their production workflows.
| |
| | |
| * '''Scientific and Engineering''': The availability of specialized software like Mathematica and various CAD packages, combined with the ability to add high-resolution graphics cards, made the Macintosh II popular in research institutions and engineering firms.
| |
| | |
| * '''Financial Services''': Wall Street firms embraced the Macintosh II for financial modeling and analysis, with companies like Morgan Stanley and Goldman Sachs deploying hundreds of units.
| |
| | |
| === Sales Performance ===
| |
| | |
| First-year sales exceeded Apple's projections, with approximately 50,000 units sold in 1987 despite production constraints. By 1988, monthly production had ramped up to over 15,000 units, making the Macintosh II family Apple's most successful product line in terms of revenue. The high average selling price, often exceeding $10,000 for fully configured systems, contributed significantly to Apple's profitability during this period.
| |
| | |
| Market research firm Dataquest reported that the Macintosh II helped Apple increase its share of the workstation market from virtually zero to 8.5% within 18 months of launch. This success prompted competitors including IBM and Compaq to accelerate development of their own high-end graphics workstations.
| |
| | |
| === Developer Response ===
| |
| | |
| Software developers responded enthusiastically to the Macintosh II's capabilities. Major applications were quickly updated to support color, and new categories of software emerged to take advantage of the system's power. Adobe Systems accelerated development of Photoshop specifically for the Macintosh II, while companies like Aldus and Quark enhanced their desktop publishing applications with advanced color support.
| |
| | |
| The availability of development tools and the relatively straightforward process of creating NuBus expansion cards encouraged a thriving third-party hardware ecosystem. Companies like Radius, SuperMac, and RasterOps developed innovative video cards and accelerators that extended the Macintosh II's capabilities far beyond its original specifications.
| |
| | |
| == Cultural Impact ==
| |
| | |
| === Transformation of Creative Industries ===
| |
| | |
| The Macintosh II fundamentally transformed several creative industries through its combination of processing power, color graphics capabilities, and intuitive interface. In graphic design, the system enabled a shift from traditional paste-up techniques to completely digital workflows. Design firms could now create, edit, and output full-color compositions entirely within the digital domain, dramatically reducing production time and costs.
| |
| | |
| The advertising industry experienced a similar revolution. Agencies adopted Macintosh II systems for concept development, storyboarding, and even early forms of digital video editing. The ability to quickly iterate on creative concepts and present full-color comprehensives to clients changed the fundamental dynamics of the creative process.
| |
| | |
| In architecture and industrial design, the Macintosh II democratized access to CAD technology. Previously, such capabilities required expensive dedicated workstations from companies like Silicon Graphics or Intergraph. The Macintosh II, while still expensive, offered similar functionality at a fraction of the cost, enabling smaller firms to compete with larger establishments.
| |
| | |
| === Educational Impact ===
| |
| | |
| Universities and colleges rapidly adopted the Macintosh II for both teaching and research. Computer science departments used the systems for graphics programming and user interface research, while art and design programs integrated them into their curricula. The Massachusetts Institute of Technology's Media Lab became an early showcase for the Macintosh II's capabilities, using the systems for pioneering work in multimedia and interactive design.
| |
| | |
| The presence of Macintosh II systems in educational institutions created a generation of students familiar with graphical computing and desktop publishing concepts. This educational exposure created a skilled workforce that would drive the digital revolution of the 1990s.
| |
| | |
| === Influence on Computing Industry ===
| |
| | |
| The Macintosh II's success demonstrated the viability of high-end personal computers in professional markets, influencing the entire industry's direction. IBM accelerated development of the PS/2 Model 80, while Compaq introduced the DeskPro 386/25, both attempting to match the Macintosh II's capabilities in the DOS/Windows environment.
| |
| | |
| The system's modular architecture influenced Apple's design philosophy for years to come. The concept of a professional desktop computer with expansion slots would persist through the Quadra and Power Macintosh lines, only
| |
| | |
| == Technical Analysis ==
| |
| | |
| The Macintosh II represented a fundamental architectural departure from previous Macintosh computers, introducing an open architecture design that would define professional Macintosh systems for years to come. Released in March 1987, it was Apple's first modular Macintosh and the first to support color graphics natively.
| |
| | |
| === System Architecture ===
| |
| | |
| At the heart of the Macintosh II was the Motorola 68020 processor running at 16 MHz, a significant upgrade from the 68000 used in earlier Macintosh models. The 68020 featured a full 32-bit architecture with 32-bit data and address buses, so the processor itself can address 4 GB. '''The machine cannot''': Apple's published maximum is 8 MB<ref name="ssmacintoshiiiixii" />, because the Macintosh II ROM is not 32-bit clean. A "128 MB" practical limit was previously stated here and is wrong by an order of magnitude. The processor included 256 bytes of on-chip instruction cache, improving performance for frequently executed code sequences.
| |
| | |
| The logic board takes up to '''8 MB''' in eight 30-pin SIMM slots<ref name="ssmacintoshiiiixii" />. Virtual memory under [[A/UX]] requires a '''PMMU''', which Apple lists as '''optional''' on the Macintosh II and built in on the IIx and IIfx<ref name="ssmacintoshiiiixii" /> — so an A/UX-capable Macintosh II is one with the PMMU fitted, and that is worth checking before buying one for that purpose. A "dual-channel memory access" description and a family of "Apple Silicon Integration (ASI)" chips were previously described here; neither term appears in any Apple document and both have been removed.
| |
|
| |
|
| === Expansion Capabilities === | | == Documentation == |
| | * [[Macintosh II/IIx/IIfx Service Source]]: Apple's service manual for the family, with specifications, symptom charts, take-apart, upgrades, battery procedures and exploded view.<ref name="ss" /> |
| | * [[Macintosh II Repair and Upgrade Secrets]]: Larry Pina's 1991 repair and upgrade book for the II family.<ref name="pina" /> |
|
| |
|
| The Macintosh II's defining characteristic was its six [[NuBus]] expansion slots, making it the first truly expandable Macintosh. NuBus, originally developed at MIT and refined by Texas Instruments, provided a 32-bit, processor-independent expansion bus running at 10 MHz. Each slot could theoretically transfer data at 40 MB/second, though real-world performance was typically lower due to arbitration overhead and system constraints.
| | == Gallery == |
| | <gallery mode="packed" heights="200"> |
| | File:XC68020 top p1160084.jpg|Motorola 68020 |
| | File:Motorola 68881.jpg|Motorola 68881 FPU |
| | </gallery> |
|
| |
|
| The NuBus architecture was self-configuring, implementing an early form of plug-and-play functionality. Each card contained a declaration ROM that the system would read during startup, automatically configuring interrupts, memory mapping, and driver loading. This eliminated the need for DIP switches or jumpers common on IBM PC-compatible systems of the era.
| | == Related pages == |
| | | * [[Macintosh IIx]] |
| === Graphics Subsystem ===
| | * [[Macintosh IIfx]] |
| | | * [[Macintosh IIcx]] |
| Unlike previous Macintosh models with built-in displays, the Macintosh II required a separate graphics card. Apple offered several options, with the most popular being the Macintosh II Video Card (also known as the Toby card). This card supported multiple resolutions and color depths:
| | * [[Macintosh IIci]] |
| | | * [[Macintosh HDD Maintenance]] |
| * 640×480 at 8-bit color (256 colors)
| | * [[Macintosh Floppy Drive Maintenance]] |
| * 640×480 at 4-bit color (16 colors)
| | * [[Battery Refurbishment]] |
| * 640×480 at 1-bit (monochrome) | |
| | |
| The video subsystem uses a palette-based colour system with a Color Look-Up Table (CLUT), so 256 colours are chosen from 16.7 million. Video memory is on the card, not in main memory. '''A VRAM size and a portrait display mode were previously attributed to the standard card here and could not be sourced'''; the resolutions a given Macintosh II supports depend entirely on which card is fitted, and Apple's own Specifications chapter for this machine lists no built-in video at all.
| |
| | |
| === Storage and I/O ===
| |
| | |
| The internal hard drive was optional, in 40, 80 or 160 MB sizes, and Apple's SCSI specification for this machine is an '''eight device maximum''' at '''5 MB/sec'''<ref name="ssmacintoshiiiixii" />. The SCSI implementation supported asynchronous transfers at up to 5 MB/second, though actual throughput was limited by drive mechanics and controller efficiency.
| |
| | |
| The system featured comprehensive I/O capabilities:
| |
| * Two [[Apple Desktop Bus]] (ADB) ports for keyboards, mice, and other input devices
| |
| * Two serial ports (RS-422) for printers, modems, and [[LocalTalk]] networking | |
| * One external SCSI port (DB-25 connector)
| |
| * Ethernet and Token Ring by NuBus card. There is '''no''' built-in network interface on a Macintosh II
| |
| | |
| === Power Supply and Thermal Design ===
| |
| | |
| Apple's figure is '''220 W maximum, not including the monitor''', from a '''100–240 VAC
| |
| automatically configured''' input at '''48–62 Hz'''<ref name="ssmacintoshiiiixii" />. (The IIfx is 230 W.) Figures of
| |
| 230 W and 231 W appeared elsewhere on this page and in its infobox; 220 W is Apple's.
| |
| | |
| '''Two claims about this supply have been removed as fabrications.''' It does '''not''' have
| |
| power factor correction — PFC did not appear in desktop supplies until the 1990s and appears in no
| |
| Apple document for this machine. And there is no "multi-zone cooling system with
| |
| temperature-controlled fans", no temperature sensor driving a variable-speed fan, and no separate
| |
| fan inside the power supply: the Macintosh II has one fan.
| |
| | |
| '''Apple publishes no rail tolerance and no power-supply adjustment for the Macintosh II.''' The
| |
| "+5 V 4.85–5.15 V / +12 V 11.90–12.75 V" pair that circulates on this wiki is Apple's
| |
| '''Macintosh Plus and 128K/512K''' procedure, measured at the external drive port with voltage
| |
| test cable 077-0135.
| |
| | |
| '''The battery is not one cell.''' Apple's Battery Verification and Battery Replacement procedures
| |
| for the II, IIx and IIfx are headed '''"Lithium Batteries"''' throughout and warn that "the lithium
| |
| batteries in the computer could explode" — there are '''two''' ½AA cells on the logic board, not
| |
| one. Apple's threshold is '''replace below 3.2 V''', measured on the 10 V DC range with the cover
| |
| and drive mount removed, holding the positive probe to the end marked "+" on the logic
| |
| board.<ref name="ssmacintoshiiiixii" />
| |
| | |
| == Comparisons ==
| |
| | |
| === Contemporary Macintosh Systems ===
| |
| | |
| When compared to the [[Macintosh SE]] released the same year, the Macintosh II represented a completely different class of computer. While the SE maintained the compact all-in-one design with a 9-inch monochrome display and 68000 processor, the Macintosh II offered:
| |
| | |
| * 2-4 times the processing power (16 MHz 68020 vs 8 MHz 68000)
| |
| * Color graphics capability vs monochrome only
| |
| * Expandability through NuBus vs single Processor Direct Slot
| |
| * Up to 128 MB RAM capacity vs 4 MB maximum
| |
| * Multiple display support vs fixed internal display | |
| | |
| The [[Macintosh IIx]], introduced in 1988, was essentially a Macintosh II with the 68030 processor and 68882 FPU as standard equipment. The architectures were otherwise identical, allowing most Macintosh II systems to be upgraded to IIx specifications through a logic board swap.
| |
| | |
| === IBM PC Compatibles ===
| |
| | |
| Against IBM PC-compatible systems, the Macintosh II competed primarily with high-end 80386-based machines. The [[IBM PS/2 Model 80]], introduced several months after the Macintosh II, offered comparable expandability with its Micro Channel Architecture (MCA) bus. However, key differences included:
| |
| | |
| * NuBus's automatic configuration vs MCA's requirement for configuration diskettes
| |
| * Superior graphics capabilities with built-in 24-bit color support
| |
| * More sophisticated operating system with cooperative multitasking | |
| * Higher entry price ($5,498 base vs approximately $3,995 for comparable PC systems)
| |
| | |
| The [[Compaq Deskpro 386]] provided strong competition with similar performance at a lower price point, though it lacked the Macintosh II's integrated approach to graphics and multimedia.
| |
| | |
| === Workstation Competitors ===
| |
| | |
| The Macintosh II also competed with entry-level workstations from established vendors. The [[Sun 3/60]] offered similar 68020-based performance with Unix as the standard operating system. However, the Macintosh II provided:
| |
| | |
| * Superior ease of use through the Macintosh graphical interface
| |
| * Better commercial software availability | |
| * Lower entry price for color graphics configurations
| |
| * Stronger multimedia and desktop publishing capabilities
| |
| | |
| The [[Apollo DN3000]] and [[HP 9000 Series 300]] workstations offered superior floating-point performance and networking capabilities but at significantly higher prices and with steeper learning curves.
| |
| | |
| == Legacy ==
| |
| | |
| === Industry Impact ===
| |
| | |
| The Macintosh II fundamentally changed Apple's position in the computer industry, establishing the company as a serious competitor in professional and business markets. Its introduction of color graphics to the Macintosh platform enabled entirely new categories of software, particularly in graphic design, video production, and scientific visualization.
| |
| | |
| The system's open architecture philosophy influenced all subsequent professional Macintosh designs through the [[Power Mac G5]] in 2003. The NuBus expansion standard, while eventually replaced by PCI, established principles of automatic configuration and ease of expansion that influenced the entire industry.
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| === Desktop Publishing Revolution ===
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| Building on the foundation established by the original Macintosh and [[LaserWriter]], the Macintosh II accelerated the desktop publishing revolution. Its color capabilities enabled:
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| * Full-color page layout and design
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| * Professional photo retouching with early versions | |
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| == Service documentation ==
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| Apple's own service manual is hosted here as [[Macintosh II/IIx/IIfx Service Source]]. It gives
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| the Macintosh II as a '''Motorola 68020 at 15.6772 MHz''' with an optional PMMU, the supply as
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| '''100–240 VAC''' automatically configured at '''48–62 Hz''' drawing '''220 W''' excluding the
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| monitor, and the PRAM cell threshold as '''replace below 3.2 V'''.<ref name="ssmacintoshiiiixii">Apple Computer, ''Macintosh II/IIx/IIfx'', Service Source, 87 pp, PDF distilled 1 December 1995. Hosted here as the wiki page linked above ([[:File:macintosh_ii.iix.iifx.pdf]]). Specifications chapter, and Additional Procedures — Battery Verification where a threshold is quoted.</ref>
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| Larry Pina measured the same cells independently and the two agree: the Tadiran 3.6 V lithium cells
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| read '''3.2–3.85 V''' when good, 2.3–3.1 V when weak, and are '''dead below 2.3 V''' — so Apple's
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| 3.2 V threshold is the bottom of the healthy band rather than a failure point.<ref name="pina91">Larry Pina, ''Macintosh II Repair and Upgrade Secrets'', Brady Publishing (Simon & Schuster), 1991, ISBN 0-13-929530-5. Hosted here as [[Macintosh II Repair and Upgrade Secrets]]. Chapter 4, testing B2. Secondary source.</ref>
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| == References == | | == References == |
| <references /> | | <references /> |
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| | {{Navbox-AppleVintage}} |
| [[Category:Apple Vintage Computers]] | | [[Category:Apple Vintage Computers]] |
| {{Navbox-AppleVintage}}
| | [[Category:Macintosh II series]] |
Motorola 68020
Motorola 68881 FPU
