The Atari 520ST was presented at the winter ESC in January 1985, six months before the Commodore Amiga. However, Atari took some shortcuts, as the operating system did not yet exist in ROM, and had to be loaded from floppy disk on power-up (but then again, so did the Amiga). The Atari 520ST It also did not have an internal floppy drive, but later versions included one.
With a 3.5-inch 360K external floppy disk drive, a mouse and a monochrome monitor, it came out at a cost of $799.
Atari 520ST data sheet
|CPU:||Motorola 68000 @ 8MHz|
|Display:||320 X 200 - 16 colours|
|640 X 200 - 4 colours|
|640 X 400 - monochrome|
|Ports:||RGB, cartridge, parallel, serial, HD|
|floppy drive, MIDI (2), joystick, mouse|
|Storage:||external SSDD 360K floppy drive|
Both the Amiga and the Atari 520ST are based on the Motorola 68000 CPU, which has a 16-bit external bus and a 32-bit internal bus, so the 520 'ST' stands for 'sixteen/thirty-two'. The operating system is 'TOS', or 'Tramiel Operating System'.
The Atari 520ST (and the Amiga) have a graphical operating system, or GUI, similar to Apple's Macintosh, which was released a year earlier. The 520ST used Digital Research's GEM graphical user interface, although it is not as nice as that of the Macintosh or the Amiga.
One thing that IS very good is the built-in VT52 emulation. The Atari 520ST can act as a dumb terminal, communicating through its serial port with another system.
There was a great rivalry between Amiga and Atari users, each of whom was convinced that their computer system was superior, or at least they expected it to be.
In addition to the Atari 520ST, the company released the Atari 1040ST, with an integrated floppy drive and 1Mb of RAM (the 520ST has 512Kb). Four years later, in 1989, the portable Atari ST computer, the Stacy, appeared.