Editing Atari Transputer Workstation

{{Hatnote|"ABAQ" redirects here. ABAQ is also the callsign for TV station [[ABQ]] in Alpha, Queensland.}}
{{Infobox computing device
| name = Atari Transputer Workstation
| title =
| aka = ATW-800, ATW, Abaq
| logo =
| image = Atw front.jpg
| caption = Front view
| developer =
| manufacturer = [[Atari Corporation]]
| family =
| type = [[workstation]]
| generation =
| releasedate={{Start date and age|1989|05}}
| lifespan =
| price =
| discontinued = Yes
| unitssold =
| unitsshipped = 350<ref name=ram1/>
| media =
| os = [[HeliOS]]
| power =
| soc =
| cpu = 20 MHz T800-20 [[Transputer]]
| memory = 4 MB of [[Random-access memory|RAM]] (expandable to 16&nbsp;MB)
| storage =
| memory card =
| display =
| graphics = Blossom video system with 1&nbsp;MB of [[dual-ported RAM]]
| sound =
| input = Complete miniaturized [[Atari ST|Mega ST]] acting as an [[input/output|I/O]] processor with 512&nbsp;KB RAM
| controllers =
| camera =
| touchpad =
| connectivity =
| platform =
| service =
| dimensions =
| weight =
| topgame =
| compatibility=
| predecessor =
| successor =
| related =
| website = <!--{{URL|example.org}} -->
}}
The '''Atari Transputer Workstation''' (also known as '''ATW-800''', or simply '''ATW''') is a [[workstation]] class computer released by [[Atari Corporation]] in the late 1980s, based on the [[INMOS]] [[Transputer]]. It was introduced in 1987 as the '''Abaq''', but the name was changed before sales began.<ref>{{cite news
|last1=Moran
|first1=Tom
|date=12 October 1987
|url=https://books.google.com/books?id=FzwEAAAAMBAJ&dq=Atari+Transputer+Workstation&pg=PA6
|title=Atari to Display Transputer Based Workstation at Comdex
|work=[[InfoWorld]]
|page=6
|volume=9
|issue=49
}}</ref><ref>{{cite news
|last1=Mace
|first1=Scott
|date=8 February 1988
|url=https://books.google.com/books?id=DD8EAAAAMBAJ&dq=Atari+Transputer+Workstation&pg=PT75
|title=News:CPU Design:RISC Chips Promise Performance Boot
|work=[[InfoWorld]]
|volume=10
|issue=6
|page=81
|quote=...Atari's Abaq computer is based on the Inmos T0800 RISC chip...
}}</ref><ref>{{cite magazine
|last1=Hebditch
|first1=David
|last2=Anning
|first2=Nick
|date=28 April 1988
|url=https://books.google.com/books?id=GDEnVIFJpt4C&dq=Atari+abaq&pg=PA50
|title=Parallel thinking for powerful chip
|magazine=New Scientist
|page=54
|volume=118
|issue=1610
|quote=...The basic Abaq will cost between $4000 and $5000...
}}</ref> Sales were almost non-existent, and the product was canceled after only a few hundred units were made.

== History ==
In 1986, Tim King<ref>[https://www.tim-king.com ...Later he became involved in parallel operating systems and novel architecture processors (remember the Transputer?)...] Tim King</ref> left his job at [[MetaComCo]], along with a few other employees, to start [[Perihelion Software]] in England. There they began developing a new parallel-processing [[operating system]] named ''[[HeliOS]]''. At about the same time a colleague, Jack Lang, started Perihelion (later Perihelion Hardware) to create a new Transputer-based workstation that would run HeliOS.

While at MetaComCo, much of the Perihelion Software team had worked with both Atari Corp. and [[Commodore International]], producing the [[programming language]] [[Atari ST BASIC|ST BASIC]] for the former, and [[AmigaDOS]] for the latter. The principals still had contacts with both companies. Commodore had expressed some interest in their new system, and showed demos of it on an add-on card running inside an [[Amiga 2000]]. It appears they later lost interest in it. Atari Corp. met with Perihelion and work began on what would eventually become the Atari Transputer Workstation.

The machine was first introduced at the November 1987 [[COMDEX]] with the name Abaq.<ref name=ram1>Ram Meenakshisundaram, [http://www.classiccmp.org/transputer/rtu_atw800.htm "Ram's Totally Unofficial Atari Transputer Workstation 800 Pages"]</ref><ref>{{cite news
|last1=Stephens
|first1=Mark
|date=9 November 1987
|url=https://books.google.com/books?id=Sj0EAAAAMBAJ&dq=Atari+abaq&pg=PA5
|title=Atari Floods Comdex with Products
|work=[[InfoWorld]]
|volume=9
|issue=45
|page=5
|quote=...a radical computing engine based on the Inmos T- 800 RISC processor. According to Atari president Sam Tramiel, the Transputer-based Abaq requires a 4-mega-byte Atari Mega workstation front end to handle I/O...
}}</ref> Two versions were shown at the time; one was a card that connected to the Mega ST bus expansion slot, the second version was a stand-alone tower system containing a miniaturized Mega ST inside.<ref>[https://www.old-computers.com/museum/computer.asp?c=33&st=1 "Abaq ATW Transputer 800"] {{Webarchive|url=https://web.archive.org/web/20101121035818/http://www.old-computers.com/museum/computer.asp?st=1&c=33 |date=2010-11-21}}, image shows the unreleased single-card solution</ref> The external card version was dropped at some point during development. It was later learned that the "Abaq" name was in use in Europe, so the product name was changed to ATW800. Perihelion remained the exclusive distributor in England. A first run of prototypes was released in May 1988, followed by a production run in May 1989. In total, only 350 machines were produced (depending on the source either 50 or 100 of the total were prototypes).<ref name=ram1/>

The team in charge of the ATW's video system, "Blossom", would later work on another Atari project, the [[Atari Jaguar]] video game console.

== Overview ==
{{Multiple image
| direction = vertical
| width = 200
| header = System views
| image2 = Atw inside.jpg
| caption2 = Inside
| image3 = Atw subsys.jpg
| caption3 = MegaST I/O subsystem
| image4 = Atw blossom.jpg
| caption4 = Blossom board
| image5 = Atw farmcard.jpg
| caption5 = Farmcard
}}
{{More citations needed|section|date=March 2021}}
The Atari Transputer Workstation system consists of three main parts:

# the main motherboard containing a T800-20 Transputer and 4&nbsp;MB of [[random-access memory]] (RAM) (expandable to 16&nbsp;MB)
# a complete miniaturized [[Atari ST|Mega ST]] acting as an [[input/output]] (I/O) processor with 512&nbsp;KB of RAM
# the Blossom video system with 1&nbsp;MB of [[dual-ported RAM]]

All of these are connected using the Transputer's 20&nbsp;Mbit/s processor links. The motherboard contains four slots for added ''farm cards'' containing four Transputers each, meaning that a fully expanded ATW contains 17 Transputers.<ref>{{cite web
|url=https://www.atarimuseum.com/computers/16bits/transputer.html
|title=The Atari ABAQ/ATW800 "Transputer"
|archive-url=https://web.archive.org/web/20210703043237/http://www.atarimuseum.com/computers/16bits/transputer.html
|archive-date=3 July 2021
}}</ref> Each runs at 20&nbsp;MHz (the -20 in the name) which supplied about 10 [[Instructions per second#Millions of instructions per second (MIPS)|MIPS]] each. The bus is available externally, allowing several ATWs to be connected into one large farm. The motherboard includes a separate slot for one of the INMOS crossbar switches to improve inter-chip networking performance.

HeliOS is [[Unix-like]], but not [[Unix]]. It lacks memory protection, due largely to the lack of a [[memory management unit]] (MMU) on the Transputer, although a number of measures are employed to reduce the possibility of programs interfering with each other. For example, when invoking a command pipeline, each program is distributed to its own separate processor, communicating with other programs using pipes that are implemented by hardware links. Where many programs may be deployed on the same processor, these processors will not in general be shared by programs belonging to different users.<ref name="byte198806_transputer">{{cite magazine |last1=Pountain |first1=Dick |date=June 1988 |url=https://archive.org/details/BYTE-1988-06/page/n348/mode/1up |title=A Personal Transputer |magazine=[[Byte (magazine)|Byte]] |access-date=21 February 2024 |pages=303–304, 306, 308}}</ref>

HeliOS is Unix-like enough that it ran standard Unix utilities, including the [[X Window System]] as the machine's [[graphical user interface]] (GUI). HeliOS can run on all of the Transputers in a farm concurrently, which allows all computing tasks to be fully distributed. Powering off an ATW does not affect the overall farm, and the tasks simply move to other processors on other systems.

Blossom supports several video modes:
:mode 0: 1280 by 960 pixels, 16 colors out of a palette of 4096 (including 16 true grayscales, on a monochrome monitor)
:mode 1: 1024 by 768 pixels, 256 colors out of a palette of 16.7 million
:mode 2: 640 by 480 pixels (2 virtual screens), 256 colors out of a palette of 16.7 million
:mode 3: 512 by 480 pixels, 16.7 million colors

Blossom also includes a number of high-speed effects (128 megapixel fill rates) and [[blitter]] functionality, including the ability to apply up to four masks on a [[bit blit]] operation in a fashion similar to a modern [[graphics processing unit]]'s ability to apply several textures to a 3D object.

One oddity of the ATW is that it appears that the Blossom is responsible for the DRAM refresh, although the ATW includes such hardware internally.

The video architecture developed by Perihelion for the ATW formed the basis of a "high resolution video engine" expansion card envisaged for the [[TT030]] workstation, connecting to the machine's VMEbus and supporting direct memory access transfers to and from system RAM.<ref name="atari19890421_ttx">{{cite tech report |url=https://archive.org/details/TT-X_Spec_Apr-21-1989/page/n30/mode/1up |title=Atari TT and TT/X Product Specifications The Design of the TT Computer Series |publisher=Atari Corporation |date=21 April 1989 |access-date=22 February 2024 |pages=24}}</ref>

== References ==
{{Reflist}}

== External links ==
* [http://www.classiccmp.org/transputer/rtu_atw800.htm Ram's Totally Unofficial ATW800 Pages]
* [https://www.atarimuseum.com/computers/16bits/transputer.html Atari Transputer at Atarimuseum.com]
* [http://www.classiccmp.org/transputer/atw800.htm Atari Transputer Workstation 800 Data Sheet]
* [https://web.archive.org/web/20130515034826/http://spirit.lboro.ac.uk/emulator.html Transputer emulator] – It emulates one T414 Transputer (with no [[floating-point unit]] (FPU), no [[blitter]] instructions) and supplies the file and terminal I/O services that were usually supplied by the host computer system.
* [http://atw800.complicated.net/ Atari ATW800 information] – including Helios software, documentation and everything else for setting up ATW800
* [http://www.classiccmp.org/dunfield/atw800/index.htm Daves Old Computers – Atari Transputer Workstation] – manuals
* [http://www.hermeticaconsulting.co.uk/publications_it.html Articles written by Mike Charnley-Fisher at the time]

{{Atari}}

[[Category:Computer workstations]]
[[Category:Atari hardware|Transputer]]