Commodore 16/Plus 4

Made in USA by Commodore in 1984
Designed to replace the Commodore VIC 20
Commodore BASIC 3.5

CPU: 7501 @ 1.79 MHz (NTSC) or 1.77 MHz (PAL)
RAM: 64K in the plus/4 (59K usable), 16K in other models
ROM: 64K (for the plus/4 with built-in office suit)
Text display: 40×25

There were three varieties in this line
Commodore plus/4, Commodore 16, Commodore 116
An office suit was also built in to the plus/4. It had a word processor, spreadsheet, graphics, and database application. This is the "+4" in the name. They are compatible with each other, except that the plus/4 has 64K (59K usable) instead of the 6K of the 116/16. Many plus/4 apps won't run on the others. Programmers solved this by usually only making 16/116 apps, which meant most of them sucked despite the plus/4's strong points of more memory (the C64 only had 38K usable), a 75% faster CPU, much better graphics resolution, and vastly superior color capability over the C64 (not to mention the Vic-20).

The 7501 CPU is compatible with the 6502 but the plus/4 line is not compatible with the C64 or Vic-20. Compatibility is reduced by a different memory map, drive connector, cartridge slot, and game ports. It had no sprite capability, and no Sid chip. But, many other systems did game just fine without sprites, such as the Apple][ and the Atari ST. Note however, that the plus/4 line is far superior for games that do not need advanced sound or intensive animated graphics. RPGs, text adventures, graphical adventure games, strategy, and simulation games are ideally suited for the platform. Creative use of the built in office suite and the 59K of memory could have made for interesting features like journals, strategic reports and stats, a vast database of enemies and locations, and high resolution images. No sprites, no Sid, commercial failure, and non-standard game ports contributed to the plus/4's underappreciation as a gaming platform. The low cost (roughly half that of a C64), fast CPU, and great graphics did not makeup for the shortcomings

The Commodore 264 was a prototype Commodore plus/4. The Commodore V364 prototype included a voice synthesis chip but was otherwise similar to the plus/4 line. Critics of the Commodore plus/4 called it the Commodore minus/60, indicating the thought the Commodore 64 was far superior. plus/4 machines equipped with a modem and a strobe light were provided by the government of Denmark to the hearing impaired. Users could call a translation center who would in turn call the 2nd party the user was trying to reach. The translation center would read the users typed text aloud to the 2nd party and type their response for the hearing impaired user. Incoming calls were routed through the center also. The stobelight plugged into the plus/4 would flash to signify an incoming call. This was a lot cheaper than a specialized system (equivalent to $49 USD) and worked with an existing phone line. And the user, who could care less about a Sid chip, got a computer with functional office suite as a bonus. The circuit board contained only 9 ICs. It could have easily been made into a very tiny case.


tech info

resolution: 320 x 200 121colors (15 hues x 8 luminances + black)
memory: 16K RAM, 32K ROM
CPU: 7501
sound: 2 channels, 4 octaves + white noise

Related systems

Commodore PET1977
Commodore 641982
Commodore 16/Plus 41984
Amiga OCS1985
Commodore 1281985
Amiga AGA1992