Vital Statistics

In January 1985 Atari Corporation introduced its new 16-bit computer system, called the 520ST. "520" being the memory size and "ST" for Sixteen/Thirty-two bit processor. There were three basic flavours of the entry-level home-user ST. These were, in chronological order of introduction, the ST, the STFM and the STe. Each of these came in two varieties - the 520 (with 512Kb RAM) and the 1040 (with 1Mb RAM).

The very earliest 520ST machines came with single-sided 3.5" floppy drives (a rarity!).
The ST, STFM and STe have slightly different capabilities.

All home-user ST units support three video modes; 320x200, 16-color, 640x200, 4-color and 640x400 monochrome.

The original ST and STFM have a palette of 512 colors (three bits each for red, green and blue level); the STe supports a 4096 color palette, the same as the Amiga's. On the ST and STFM, a blitter (simple graphics coprocessor) is an optional extra; on the STe it is standard.

The STe also has easy-to-expand 30-pin SIMM sockets for up to 4Mb of internal RAM, and much more advanced sound capabilities.

The original ST and STFM use the General Instruments AY-3-8910 (closely related to the Yamaha YM2203) three-channel tone generator, a very primitive audio output device which was also used in several 8-bit platforms including the Amstrad CPC series, the Sinclair ZX Spectrum +2 and +3, and some early 8-bit arcade games such as Capcom's 1942. The STe has stereo DMA 8-bit PCM audio, very similar to the Amiga's 4-channel DMA sound system.

There are other models of ST too, including lower-end versions of the 520ST (one with 128K RAM called the 120ST, one with 256K RAM, called the 240ST), two portable versions of the machine (STacy in 1989 and ST Book in 1992) and higher-end 68030-based machines such as the TT030 and Falcon030, but these are much rarer than the models already mentioned.