Macintosh 512K

The Macintosh 512K was a personal computer made by Apple Computer. It was sold from September 1984 to April 1986. It was the second model in the Macintosh line after the Macintosh 128K.

The biggest difference from the 128K model was that the 512K had more memory — 512 kilobytes (KB). This made it better for business use and allowed it to run more software. Because of the extra memory, people called it the Fat Mac.

 Features 

 Processor and memory 
Like the 128K, the 512K used a Motorola 68000 processor at about 7.8 MHz. It had 512 KB of RAM, which could not be upgraded. It also had a 64 KB ROM chip. Some of the memory was used by the display, which made the computer slower by up to 35%.

The display resolution was 512 × 342 pixels. Apple also sold a memory upgrade for the original 128K for $995, which was later made cheaper as memory prices dropped.

 Software 
The 512K came with MacPaint and MacWrite. Later programs included MacDraw, MacProject, and Microsoft Excel. Excel required at least 512 KB of memory, which made the 512K important for business use.

Some versions of the 512K could also run Apple’s Switcher, which allowed switching between programs, although only a few at a time.

 New uses 
The 512K worked with the LaserWriter printer, and with other devices like a number pad, microphone, tablet, keyboard, and mouse. It used LocalTalk to share these devices over a network. It was the oldest Macintosh that could be used with AppleShare when that came out in 1987.

Its larger memory made it better at handling bigger documents and using the graphical user interface more smoothly.

In the 1980s, Color Systems Technology used many 512Ks linked to a custom Intel 80186-based machine to help add color to old black-and-white movies.Colorizer hopes LAN makes pockets greener, Computerworld, February 1, 1988.

 System software 
The Macintosh 512K could run System 1.1 through System 4.1. With an external hard drive (the Hard Disk 20), it could also run System Software 5.

 Upgrades 
In April 1986, Apple released the Macintosh 512Ke, an improved version of the 512K. It had a better 800 KB floppy drive and the same ROM as the Macintosh Plus. Apple also sold an upgrade kit to turn a regular 512K into a 512Ke.

Other upgrades were available too, including hard drives and memory expansions of 2 MB or more. These upgrades were expensive and required opening the computer.

 End of support 
Apple stopped supporting the Macintosh 512K on September 1, 1998.

 References 

 Other websites 
 Macintosh 512K technical specs at apple.com
 Inside the Macintosh 512K (archived)

Category:Apple hardware