The Commodore SX-64, also known as the Executive 64, was a portable, briefcase/suitcase-size "luggable" version of the popular Commodore 64 home computer and holds the distinction of being the first full-color portable computer.

The SX-64 featured a built-in five-inch composite monitor and a built-in 1541 floppy drive, and weighed 23 lb (10.5 kg). The machine was carried by its sturdy handle, which doubled as an adjustable stand (like most CRT based oscilloscopes). It was announced in January 1983 and released a year later, at US$995.

Description

Aside from its built-in features and different form factor, there were several other subtle differences between the SX-64 and the regular C64. The default screen color was changed to blue text on a white background for improved readability on the smaller screen. This sometimes caused compatibility problems with programs that assumed the C64's default blue background. In addition, the cassette port and RF port were omitted from the SX-64 because it had a built-in disk drive and monitor, and thus no need for a tape drive or television connector. The default device for load and save operations was changed to the floppy drive.

An enhanced version of the SX-64 with dual floppy drives, known as the DX-64, was announced and a few have been reported to exist, but it is very rare. Some hobbyists installed a second floppy drive themselves in the SX-64's empty drive slot. A version with a monochrome screen called the SX-100 was announced but never released.

History

The SX-64 did not sell well, and its failure has been variously attributed to its small screen, weight, marketing, and smaller business software library than that of its competitors, the Osborne 1 (Zilog Z80 CPU, CP/M OS) and Compaq Portable (16-bit CPU, MS-DOS). In addition, the Osborne and Compaq computers were faster, and in the case of the Osborne, was competitively priced.

SX-64 sales have been estimated as low as 9,000 units from 1984 to 1986, when it was discontinued.

Some would-be buyers waited instead for the announced DX-64, which never became widely available due to the slow sales of the SX-64, creating a Catch-22 situation. The SX-64 did however gain a following with user groups and software developers, who could quickly pack and unpack the machine to use for copying software or giving demonstrations.

Technical information

Like the Commodore 64, except the following:

• Built-in storage: 170KB 5¼" floppy disk drive (internal version of the Commodore 1541)
• Built-in display: 5 inch (127 mm) composite color monitor
• Keyboard: separate unit, connected by cord to CPU unit
• Cartridge port: placed on top of CPU unit, w/spring-loaded fold-in lid, cartridges inserted vertically (vs horisontally into back of C64)
• I/O connectors:
  • no Datassette interface
  • no RF modulator & connector
  • 24-pin keyboard connector below right side of front panel
  • standard three-prong AC power connector (vs DIN plug from C64 "power brick" PSU)
• Power supply: internal unit with transformer and rectifiers (vs external C64 PSU)
• Extra features: floppy disk storage compartment above disk drive