See below for specifications and information on this system.
Specifications and information
| Key Dates: | Announced December 1978 Ships October 1979 |
| CPU: | 6502, 1.79 MHz |
| Memory: | 8K |
| Operating System: | BASIC in ROM (10K ROM pack + BASIC cartridge) Atari DOS on diskette |
| Input/Output: | 4 joystick ports, Atari cable bus |
| Bus: | One cartridge slot Atari daisy-chain cable bus, connects floppy drives, cassette drive, and Atari 850 I/O interface, which includes serial and parallel ports. |
| Other Items in Collection: | Full documentation, Atari DOS 2.5 & 3.0, various cartridges & games on diskette |
The Atari 400 and 800 were launched simultaneously, although the 800 was not available in the retail channel for a few months. The membrane keyboard prohibited touch typing and limited the 400's applications to primarily games.