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Macintosh Plus

Macintosh Plus

The next big Mac!
• 1 MB of RAM expandable to 4 MB!
• A SCSI port for connecting hard drives!
• Included an 800K double-sided double-density disk drive!
• Features a keyboard with cursor keys and a numeric keypad designed to accelerate data entry!
Introduced at $2,599 in January 16th, 1986
MacWrite and MacPaint were not included, they cost $125.00 seperately.

Mac Plus
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The platinum and beige Plusses - notice the left one has writing next to the Apple Logo
and the one on the right doesn't... The one on the right was an upgraded 128K or 512K.

Beige Mac PlusBack of the Mac Plus
I found a beige Plus, the front of all Pluses have writing. (2nd pic) The back of a Mac Plus.

The Mac Plus was a major turning point for the Macintosh. Two of the Macintoshes biggest complaints were its lack of memory and speed of its disk drives.

• The 1MB model proved it had the extra memory for big applications, with the top limit of 4MB. The Macintosh Plus can accommodate memory-intensive application programs. Large models, documents, and databases are easily handled. The IBM PC world thought 640K was enough for anyone, Apple though ahead again. The IBM PC world come up with two different memory expansions, Expanded and Extended. Confusing! The Macintosh Plus has the correct memory model the first time.

• The 800K disk drive was faster then the 400K drive found in the earlier Macintoshes. This was achieved due to the drive reading with two heads at the same time. The 800K drive operates at twice the speed of the 400K drive.

• The capability to add an external SCSI hard drive really made this model shine. The speed from SCSI made the Macintosh Plus a worthy computer during 1986 and beyond. The Macintosh Plus transfers data up to six times faster through the SCSI port than through the disk drive port. Up to seven peripherals can be daisy chained to the Macintosh Plus at one time.

• A new 128K Enhanced ROM has been added to the Macintosh Plus. It offers a Hierarchical File System which allows the Macintosh Plus to operate faster and function more efficiently, improving overall system performance. It provides the user with a more efficient way to store and retrieve documents.


You can have a beige case or a platimun case. Around 1987 the color was changed to Apple's new standard case color.

The Mac Plus is used today yet for web browsing, web hosting (seriously), word processing, spreadsheet and the like. The 4MB of memory is enough to do meaningful tasks yet today!

The box the Macintosh Plus shipped in.

For AppleShare use: System 6.0.x and Finder 6.1 are installed by the AppleShare Client 6.x Installer disk. This machine can be used as an AppleShare file server.

For telecommunications use: Can use 9600 baud modem or lower, anything higher may cause problems. Stock Macintosh Plus can be placed on the Internet, with maxed 4MB of RAM memory upgrade.

Hard Drive use: Can use the Apple's HD20 - plugs into the floppy port. Or use any third-party hard drive which plugs into the modem port. Stock Macintosh Plus can use any SCSI hard drive (25 pin port on back). SCSI only - Use a 3:1 interleave. The SCSI chain starts at ID 6 then works its way down to 0 - this is the boot order of the hard drives. You can specify in the Finder which drive is the boot drive though.

Color use: Aura Systems created an external box which outputted color from a Macintosh Plus. I looked into this at one point, very expensive, about $2500.

Quick answers to your questions here!

Apple official specs


  • Introduced: 1/16/86
  • Discontinued: 10/15/90
  • Floppy Size: 800K
  • Internal HD: none none
  • Upgrade From: 128, 512, 512Ke
  • Upgrade To: none (There are many accelerators available from )
  • Form Factor: 128
  • Weight: 16.5 lbs.

Logic Board

  • Main Processor: 8 MHz 68000
  • PMMU: none
  • FPU: none
  • Data Path: 8 MHz 16-bit
  • Secondary Processor: none
  • Slots: none
  • MIPS Rating: .7


  • Memory on Logic Board: none
  • RAM Range: 1MB to 4MB
  • RAM Slots: 4 30-pin SIMM
  • RAM Type: 150 ns 256K, 1MB SIMMs in groups of 2
  • Notes: This system cannot use two-chip 1MB SIMMs.


  • Built-in Display: 9" monochrome CRT
  • VRAM Configuration: built-in CRT
  • VRAM Speed: n/a
  • VRAM Expansion: built in
  • Color Bit Depth by Screen Resolution:
  • 512x384: 1-bit
    (1-bit = Black & White, 2-bit = 4 colors, 4-bit = 16 colors, 8-bit = 256 colors, 16-bit = thousands, 24-bit = millions)
  • The maximum color depth listed for 640x870 is 8-bit, reflecting the capabilities of the Apple 15 inch Portrait Display
  • Notes: Screen size is 512x342.


  • Sound In: none
  • Sound Out: mono, 8-bit
  • Microphone Port: none


  • ADB: none
  • Video: none
  • Floppy: DB-19
  • SCSI: DB-25
  • GeoPorts:
  • Ethernet: none
  • Microphone Port Type: none
  • Ports: Printer Modem Speaker

Serial Port specs

  • AppleTalk: 230.4K baud
  • Asynchronous: 57.6K baud (maximum rate)
  • Synchronous: 920K baud (maximum rate with external clock)


  • Source: .5A 105-125V 50-60 Hz
  • Consumption: 60 W or 205.2 BTU
  • Battery Type: 4.5V alkaline, #523


  • Addressing Modes: 24-bit
  • Original System Software: 1.1
  • Original Enabler: none
  • ROM ID: $0075
  • ROM Version: $6000
  • ROM Size: 128K
  • AppleTalk Version: 19
  • System Software Supported: 1.1 2.0 2.0.1 5.0 5.1 6.0 6.0.1 6.0.2 6.0.3 6.0.5 6.0.4 6.0.7 6.0.8 7.0 7.0.1 7.1 7.5 7.5.1 7.5.3

All technical information from

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