Macintosh 512Ke

The Macintosh 512K enhanced (512Ke) was introduced on April 14, 1986 as a less expensive alternative to the top-of-the-line Macintosh Plus, which had been introduced nearly 3 months earlier. The Mac 512Ke was discontinued on September 1, 1987.

Features
The Mac 512Ke featured the same 7.8336 MHz Motorola 68000 processor, same new 800KB double-sided floppy drive, and the same 128KB ROMs as the Mac Plus, but with half as much RAM (512KB) and no SCSI port. The Mac 512Ke initially shipped in the same beige color as the original Macintosh 128K, and later in the same platinum color as the Macintosh SE. An extended Mac Plus keyboard was optional (part no. M2519).

The 512KB of RAM, new ROMs, and 800KB floppy drive allowed these Macs to take advantage of new features, such as the new Hierarchical File System, an external Apple HD20 hard disk through the existing floppy port, and support for a SCSI port (as a separate upgrade).

Upgrade paths
The previous Macintosh 512K could be upgraded to a 512Ke through the Macintosh Plus Disk Drive Kit (part no. M2516), which included new 128KB ROMs (to replace the 64KB version), an 800KB floppy drive (to replace the 400KB drive), and a Macintosh Plus System Tools disk with installation guide. The upgrade allowed older 512K systems gain many of the same features of the Macintosh Plus for a fraction of the price. An upgrade involving only a ROM swap was also available, but did not include the 800KB floppy drive. The original 128K Macs are not capable of taking advantage of this upgrade kit without first installing more RAM.

A SCSI port (along with more RAM) could be added through a more costly Macintosh Plus Logic Board Kit (part no. M2518) from Apple, which included a new logic board with the 128KB ROMs, 1MB memory, SCSI port, and a replacement rear case. Less expensive third-party upgrades were also available, and routed the SCSI port through the rear battery access door.

Included software

 * System 3.0 (3.2 after June 1986, backwards compatible to 1.0)
 * Finder 5.1 (5.3 after June 1986)

In its default configuration, the 512Ke can run up to System 4.1 with Finder 5.4. With additional memory, the maximum supported system software can be extended to 6.0.8.