---------------------------------------------------------------------------- The Florida SunFlash SBus Extension Boosts I/O Performance Of SBus-Based Systems SunFLASH Vol 25 #22 January 1991 ---------------------------------------------------------------------------- New Public SBus Committee Releases First 64-Bit Specification SANTA CLARA, Calif. --January 29, 1991-- Sun Microsystems today announced at BUSCON WEST that the industry's first 64-bit specification for a desktop I/O interconnect has been made available. This new extension of the SBus architecture will help system and add-in card developers improve the performance of SBus-based systems. It is backward-compatible with existing 32-bit SBus products. A key feature of SBus Specification Revision B.0 is the provision for a 64-bit transfer protocol. SBus is a high-performance, modular I/O interconnect for RISC workstations and servers that was designed by Sun and made available to the industry with no licensing restrictions, design fees or royalties. Anticipating increased bandwidth requirements from I/O devices, the new SBus specification allows 64 bits of data to be transferred with each clock cycle. This results in a peak bandwidth of 160 to 200 megabytes per second. The current 32-bit SBus specification has a bandwidth of 80 to 100 megabytes per second. Revision B.0 establishes SBus as the only I/O interconnect to keep pace with increasing system CPU performance. Low-cost SBus boards and systems can now be designed for such data-intensive applications as digital signal processing, multimedia and high-bandwidth networking. SBus can also attach to various backplane buses, as a mezzanine bus -- serving as a "piggy back" card -- on other systems such as Futurebus+ and VME. Another feature of Revision B.0 is the SBus Profiles, which define a standard implementation of certain functions such as addressing, burst size, data parity, error handling and time-outs. SBus cards that adhere to the Profile specifications are completely "plug and play" with any other platform or SBus card that meets these specifications. Currently, there are 65 vendors offering more than 140 SBus products and services, such as Ethernet cards, bus adapters, coprocessors, instrumentation interfaces, modem and facsimile boards, and scanner and printer interfaces. Public SBus Specification Committee The new 64-bit transfer protocol is the first modification of the original SBus specification to be released by the Public SBus Specification Committee, which was formed in September 1990 by Sun and third-party SBus vendors AZCOM, Berkeley Camera Engineering, Central Data Corporation and LSI Logic. With third-party developers serving on the committee and participating in the evolution of the SBus specification, the SBus architecture will remain completely open. The most recent company to join the committee is Motorola's Computer Group. Any SBus system or board developer is eligible for membership. Availability The new 64-bit specification is available in February from The Summit Group, (408) 395-9522; Hamilton/Avnet (800) 426-2742; Wyle (714) 851-9953; or the VME Bus - Futurebus+ Extended Architecutre International Trade Association (VITA), (602) 951-8866. For technical support, developers can contact the SBus Technical Support Group by telephone at (415) 336-3558, by facsimile at (415) 962-1411 or by electronic mail at sbustech@sun.com or sunsbustech@uunet.uu.net. Sun Microsystems, Inc., headquartered in Mountain View, Calif., is a leading worldwide supplier of network-based distributed computing systems, including professional workstations, servers and UNIX(R) operating system and productivity software. ### UNIX is a registered trademark of UNIX System Laboratories, Inc. All other products or services mentioned in this document are identified by the trademarks or service marks of their respective companies or organizations. PR contact Leiann Lee (415) 336-0597 Technical Support contact Chris Wellens (415) 336-9131 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ For information send mail to info-sunflash@sunvice.East.Sun.COM. Subscription requests should be sent to sunflash-request@sunvice.East.Sun.COM. Archives are on solar.nova.edu and paris.cs.miami.edu. All prices, availability, and other statements relating to Sun or third party products are valid in the U.S. only. Please contact your local Sales Representative for details of pricing and product availability in your region. Descriptions of, or references to products or publications within SunFlash does not imply an endorsement of that product or publication by Sun Microsystems. John McLaughlin, SunFlash editor, flash@sunvice.East.Sun.COM. (305) 776-7770.