View source for Atari ST

[[Image:520st.jpg|thumb|Atari 520ST.]]

The '''Atari ST''' was the first [[TOS Family|TOS machine]] developed by [[Atari Corporation]], being released in 1985. For the time, the ST featured a powerful processor, a large amount of memory, a colourful display, and an easy-to-use GUI operating system, all for a very cheap price. These attributes all contributed to ST representing a significant evolution in the personal computer market, and consequently it was a massive commercial success. Without this success, the [[TOS Family]] would not have existed.

The name ‘ST’ is derived from the capabilities of the Motorola 68000 processor upon which the original Atari line was based. The 68000 uses a <font size=3>'''S'''</font>ixteen-bit data bus with a <font size=3>'''T'''</font>hirty-two bit address bus.


==Features==
The original ST computers featured the following:
*[[CPU|Motorola 68000]] 32-bit Central Processor Unit (CPU) running at 8MHz.
*Integrated [[GEM]] / [[TOS]] operating system.
*RAM memory storage of 256k, 512k, or 1 Mbyte.
:512KB in the first signifcant base model, the 520 (early 260 models existed with only 256KB of memory). The 1040ST was equipped with 1MB of RAM.
*Built-in MIDI, dual joystick, floppy drive, ACSI, serial, and parallel ports.
*Sophisticated DMA peripheral access.
*Yamaha 3-voice FM sound generator.
*External 128k cartridge port.
*Integrated video controller capable of generating (320x200x16), (640x200x4), and (640x400x2) [[ST Video Modes]] from as many as 512 colors.

==Revisions==
===ST===
The original ST released in June 1985, initially only as a 520ST with 512kb of RAM, an external floppy disk, and external power supply

===ST+===
As original ST, but with factory fitted 1MB 'piggyback' upgrade

===STM=== 
The '''M''' signifying the built in RF modulator for output to television sets. The STM was the last small form factor ST - all subsequent ST's had built in power supplies.

===STF===
The '''F''' signifies a built in floppy drive, as well as internal power supply and floppy drive

===STFM=== 
Floppy, Modulator

===[[Mega ST]]===
First released in 1986, the Mega ST was aimed more at the professional and business market. Originally called the "ST1", the Mega ST featured a [[blitter]] and had a more traditional PC form factor than the ST, with the motherboard in a desktop case with separate keyboard. Initially released in 2mb and 4mb models only, a 1mb model was later released, the ''Mega 1''

===[[STE]]===
The '''E''' signifying "enhanced", seen by many as an attempt by Atari to close the gap to the [[Amiga]] OCS chipset. The STE had a number of enhancements to the chipset, including:
* A palette increase from 512 to 4096 colours
* A [[blitter]] chip, previously only included in the Mega ST
* DMA and other additions to the [[glue]] chip
* Hardware scrolling
* Stereo PCM sound output, with steroy RCA outputs
* Analog joystick ports on the left side of the case
* [[SIMM]] slots for easy memory expansion to 4MB

===[[Mega STE]]===
The Mega STE had more significant differences over the STE, compared to the Mega ST over the standard ST. As well as being in a desktop case with a separate keyboard, it featured:
* [[CPU#MC68000|68000]] switchable from 8mhz to 16mhz in software, with 16kb of cache
* A socket for a [[CPU#MC68881|68881]] or [[CPU#MC68882|68882]] [[CPU#Floating_Point_Unit_.28FPU.29|FPU]]
* Internal [[SCSI]] hard drive (connected with [[ACSI]] -> SCSI adapter board)
* 1.44MB floppy drive in later revisions
* [[VME]] expansion slot
* Apple Talk network port
* [[TOS]] 2

*Please see [[Atari ST motherboard revisions]]

==Impact==
*''It was a success, explain why - price, power. Influence, competition with Amiga''

==History==
*''Discuss development politics, Sam Tramiel leaving Atari, all that stuff''

==Video==
* [http://www.youtube.com/watch?v=I0LRPMuQ8Wk Overview of Atari ST]
* [http://www.youtube.com/watch?v=m1jscTrkeso&feature=related ATARI 520ST+ booting process, rare model with no TOS in ROM]
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[[Category:Atari computers]]