Atari 260ST
The Atari 260ST was one of the first models in the Atari ST series, introduced in 1985. It was initially shipped with only 256 KB of RAM, which proved inadequate for most applications. Furthermore, TOS (The Operating System) was not ready for ROM at launch, so early units were shipped with a floppy disk version of TOS 1.0. Later, Atari provided ROM upgrades for free to early adopters. The ST series also featured GEM (Graphical Environment Manager), which provided a graphical user interface similar to that of the Apple Macintosh.
Key Features
Processor: Motorola 68000 (8 MHz)Memory: 256 KB RAM (non-expandable)
Graphics: 320×200 (16 colors), 640×200 (4 colors), 640×400 (monochrome)
Colour: 16 colour display from a palette of 512
Sound: Yamaha YM2149 PSG (3 voices, 8-bit sound)
Storage: External floppy drive (3.5-inch, 360 KB), optional hard drive
Operating System: TOS 1.0 (disk-based initially, later available in ROM) with GEM
Atari 520ST & 520ST+
The Atari 520ST followed the 260ST, increasing RAM to 512 KB, making it more practical for gaming and productivity applications. The 520ST+ was a variant with 1 MB of RAM.
Key Features
Memory: 520ST - 512 KB, 520ST+ - 1 MB RAMOperating System: TOS 1.0 (ROM-based) with GEM
Atari 520STM
The Atari 520STM added an internal RF modulator, allowing direct connection to a television without requiring a separate monitor.
Key Features
Video Output: Added RF modulator for TV connectivityOperating System: TOS 1.02 with GEM
Atari 520STF & 1040STF
The Atari 520STF and 1040STF integrated the floppy drive and power supply into the main case, reducing cable clutter and making the system more compact.
Key Features
Storage: Built-in 3.5-inch floppy driveMemory: 520STF - 512 KB RAM, 1040STF - 1 MB RAM
Operating System: TOS 1.02 with GEM
Atari 520STFM & 1040STFM
The Atari 520STFM and 1040STFM built upon the STF models by adding an RF modulator for TV output.
Key Features
Video Output: Built-in RF modulator for TV connectivityOperating System: TOS 1.04 ("Rainbow TOS") with GEM
Atari 520STE & 1040STE
The Atari 520STE and 1040STE were enhanced versions featuring improved graphics, a blitter chip for faster screen updates, better sound, and upgradable RAM.
Key Features
Graphics: Improved blitter chip for faster renderingColour: 16 colour display from a palette of 4096
Sound: Enhanced DMA stereo sound
Memory: Expandable RAM (up to 4 MB)
Operating System: TOS 1.06 / 1.62 with GEM
Legacy
The Atari ST series was a significant line of personal computers, particularly in Europe, where it was used for gaming, music production, and desktop publishing. The inclusion of GEM as a graphical interface made it a strong competitor to early Macintosh systems. The later STE models showcased Atari’s attempts to modernize the ST platform before the eventual shift to the Atari Falcon.