8/14/2019 MBus (SPARC) - Wikipedia, The Free Encyclopedia
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MBus module, Sun
SuperSPARC II SM71
Two MBus slots, one
occupied by CPU module
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 withSBus, 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 motherboardto lower manufacturing costs.
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.
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
11/7/2009 MBus (SPARC) - Wikipedia, the free en
en.wikipedia.org/wiki/MBus_(SPARC) 1
8/14/2019 MBus (SPARC) - Wikipedia, The Free Encyclopedia
2/2
MBus male connector
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.
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