Mbus (sparc) - Wikipedia, The Free Encyclopedia

11/7/2009

MBus (SPARC) - Wikipedia, the free en…

MBus (SPARC) From Wikipedia, the free encyclopedia

MBus is a computer bus designed and implemented by Sun Microsystems for communication between high speed computer system components, such as the central processing unit, motherboard and main memory. Contrast this with SBus, used in the same machines to connect add-on cards to the motherboard. MBus was first used in Sun's first multiprocessor SPARC-based system, the SPARCserver 600MP series (launched in 1991), and later found use in the SPARCstation 10 and SPARCstation 20 workstations. The bus permitted the integration of several microprocessors on a single motherboard, in a multiprocessing configuration with up to eight CPUs packaged in detachable MBus modules. However, in practice, the number of processors per MBus was limited to four. Single processor systems were also sold that used the MBus protocol internally, but with the CPUs permanently attached to the motherboard to lower manufacturing costs.

MBus module, Sun SuperSPARC II SM71

MBus specified a 64-bit datapath, which used 36-bit physical addressing, giving an address space of 64 GB. The transfer rate is 80 MB/s (320 MB/s peak). Bus controlling is done by an arbiter. Interrupt, reset, and timeout logic are also specified. Several related buses were also developed: XBus a packet-switched bus used in the SPARCserver 1000, SPARCcenter 2000 and Cray CS6400. This corresponded to the circuit-switched MBus, with identical electrical characteristics and physical form factor but an incompatible signalling protocol.

Two MBus slots, one occupied by CPU module

KBus a high-speed interconnection system for linking multiple MBuses, used in Solbourne Series 6 and Series 7 computer systems. Manufacturers who produced computer systems using the MBus included Sun, Ross Technology, Inc., Hyundai/Axil, Fujitsu, Solbourne Computer, Tatung, GCS, Auspex, ITRI, ICL, Cray, Amdahl, Themis and DTK.

See also List of device bandwidths

External links en.wikipedia.org/wiki/MBus_(SPARC)

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11/7/2009

MBus (SPARC) - Wikipedia, the free en…

The Rough Guide to MBus Modules, sunhelp.org (http://mbus.sunhelp.org/) Retrieved from "http://en.wikipedia.org/wiki/MBus_(SPARC)" Categories: Computer buses | Sun Microsystems hardware This page was last modified on 1 October 2009 at 00:59. Text is available under the Creative Commons Attribution-ShareAlike License; additional terms may apply. See Terms of Use for details. Wikipedia® is a registered trademark of the Wikimedia Foundation, Inc., a non-profit organization.

MBus male connector

en.wikipedia.org/wiki/MBus_(SPARC)

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