Macintosh Plus

The Macintosh Plus was released in 1986 and provided a number of improvements over the original Macintosh 128K and Macintosh 512K models. The Plus is powered by the Motorola 68000 at 8MHz and offers 1MB RAM, 800KB disk drive and external SCSI support.

Overview

The Macintosh Plus personal computer gives you the most im­portant benefits of the Macintosh family - power, versatility, and ease of use - in an affordable, entry-level system. Like others in the Macintosh family, the Macintosh Plus is simple to learn and use. It pro­vides high-resolution text and graphics, and features plug-in compatibility with the AppleTalk network, the Apple LaserWriter and LaserWriter Plus printers.

In addition, the Macintosh Plus offers more memory, more storage space, and more room to expand than previous Macintosh systems. That means faster execution of most programs - no waiting for parts of the program to be load­ed from disk. More disk storage space means less disk swapping and faster loading of important information. The ability to add more peripherals means you can expand your Macintosh system with the accessories you need. These features, together with an improved operating system, enhance system performance so that the Macintosh Plus can oper­ate as much as 50 percent faster than its predecessors.

General Information

CPU

MC68000; 32-bit internal data bus; 7.83-megahertz clock speed.

RAM

1 megabyte RAM, expan­dable to 4 megabytes in a socketed SIMMs (Single Inline Memory Module) configuration.

ROM

128K ROM includes:

• Hierarchical File System
• Drivers for 800K disk drive, Apple Hard Disk 20SC drive, AppleTalk network, and SCSI port
• Faster QuickDraw graphics
• RAM caching support

Notes

• For prolonged use of the Plus, especially for units where an internal hard disk has been outfitted, a "system saver" is recommended to protect the system against overheating. The Plus did not ship with an internal fan and the "system saver" attaches to the top of the unit and provides a fan.
• From MacsBug or the interrupt debugger, enter "G 40E118" (that's a zero, not an oh). (To get into the interrupt debugger, press the button on the left side of your machine closer to the back. If you're running System 7, just Shut Down your machine, then while the "you may turn off your Macintosh safely" dialog is displayed, press the button.) This gives you a tiny "Stolen from Apple Computer" message in the upper left-hand corner of your screen.

Diagrams/Schematics

Gallery

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Documentation

• Macintosh Plus Service Source
• Macintosh Plus Brochure (1986)

External Resources

• https://archive.org/details/TheDeadMacScrolls - Troubleshooting/repair information for compact Macs
• https://cdn.preterhuman.net/texts/computing/Apple_Service_PDF/68k_Macintosh/macintosh_plus.pdf - Apple Service PDF
• http://www.ccadams.org/se/classicmac2.pdf - Classic Mac Repair Notes

See Also

• Apple Computer
• Macintosh Plus Keyboard M0110A

The Compact Macintosh Family from Apple Computer

Macintosh 128K -- Macintosh 512K -- Macintosh Plus -- Macintosh SE -- Macintosh SE/30 -- Macintosh Classic -- Macintosh Classic II -- Macintosh Color Classic -- Macintosh Color Classic II