Editing Jazz (computer)

{{Short description|Computer architecture}}
{{Multiple issues|
{{prose|date=August 2011}}
{{More citations needed|date=October 2024}}
}}
The '''Jazz''' computer architecture is a motherboard and chipset design originally developed by [[Microsoft]] for use in developing [[Windows NT]]. The design was eventually used as the basis for most [[MIPS architecture|MIPS]]-based Windows NT systems.

In part because Microsoft intended NT to be portable between various [[microprocessor]] architectures, the [[MIPS architecture|MIPS]] [[RISC]] architecture was chosen for one of the first development platforms for the NT project in the late 1980s/early 1990s. However, around 1990, the existing MIPS-based systems (such as the [[TURBOchannel]]-equipped [[DECstation]] or the [[SGI Indigo]]) varied drastically from standard [[Intel]] [[personal computer]]s such as the [[IBM AT]]&mdash;for example, neither used the [[Industry Standard Architecture|ISA]] bus so common in [[Intel 80386|Intel 386]]-class machines.

For those and other reasons, Microsoft decided to design their own MIPS-based hardware platform on which to develop NT, which resulted in the Jazz architecture. Later, Microsoft sold this architecture design to the [[MIPS Technologies|MIPS Computer Systems, Inc.]] where it became the [[MIPS Magnum]].

==Architecture==
The Jazz systems were designed to partially comply with the [[Advanced RISC Computing]] (ARC) standard, and each used the ARC firmware to boot Windows NT.<ref name="f124">{{cite web | title=LinuxMIPS | website=web.archive.org | date=2007-04-17 | url=https://web.archive.org/web/20080505015443if_/http://www.linux-mips.org/wiki/Jazz | access-date=2024-06-25}}</ref> Other operating systems were also ported to various Jazz implementations, such as [[RISC/os]] to the MIPS Magnum.

The Jazz architecture includes:
* a MIPS [[R4000]]/[[R4400]] or compatible microprocessor
* an [[Extended Industry Standard Architecture|EISA]] bus
* a [[framebuffer]] for video output (the [[G364 framebuffer]])
* [[PS/2 connector]]s for mouse and keyboard
* a floppy-disk controller
* onboard 16-bit sound system
* onboard [[National Semiconductor]] [[SONIC (Ethernet controller)|SONIC]] Ethernet
* onboard [[NCR 53C9x]] SCSI chipset for [[hard disk]] and [[CD-ROM]] interface
* standard IBM AT [[Serial port|serial]] and [[parallel port]]s
* IBM AT-style time-of-year clock

This design was simple enough and powerful enough that a majority of Windows NT-capable MIPS systems were based on modified versions of the Jazz architecture. A list of systems which more or less were based on Jazz includes:
* [[MIPS Magnum]] (R4000 PC-50 and SC-50 versions)
* [[Acer PICA]]{{snd}} uses [[S3 Graphics|S3]] videocard
* [[Olivetti]] M700{{snd}} has different video and sound system
* [[NEC RISCstation]]{{snd}} Jazz with [[Peripheral Component Interconnect|PCI]]

==Systems==
There were also some MIPS systems designed to run Windows NT and comply with the ARC standard, but nevertheless were ''not'' based on the Jazz platform:
* [[DeskStation Tyne]]
* NeTpower FASTseries Falcon
* [[ShaBLAMM! NiTro-VLB]]
* [[Siemens-Nixdorf]] RM-200, RM-300 and RM-400

==References==
{{Reflist}}

== External links ==
* Linux-MIPS [http://www.linux-mips.org/wiki/Jazz Jazz] article
* [http://www.netbsd.org/Ports/arc/ NetBSD/arc]

{{Microsoft hardware}}

[[Category:Advanced RISC Computing]]
[[Category:Microsoft hardware]]
[[Category:MIPS architecture]]
[[Category:Motherboard]]