June 2005 Update

Editor’s Note: The most recent VSO meeting was held May 18-19, 2005 in Long Beach, California. The comments listed here were provided to VMEbus Systems prior to that meeting. Ed.

VSO ANSI accreditation
Accredited as a Standards Development Organization (SDO) in June 1993 by the American National Standards Institute (ANSI), the VITA Standards Organization (VSO) meets every two months to address vital embedded bus and board industry standards issues. Information on ANSI/VITA standards is available on the VITA website.

VSO study and working group activities
Standards within the VSO may be initiated by a study group, and developed by a working group. A study group requires only one VSO member, and is used to build interest in a standard. A working group requires at least three VITA members, and the proposed work must fit within the defined scope of VITA’s accreditation with ANSI.

VITA 41.0 – VME Switched Serial (VXS)
The VXS family of draft standards provides a method for implementing various serial fabric architectures within the VMEbus framework. The base draft VITA 41.0, VXS, completed a working group ballot in early April. The working group is reviewing comments and will decide if changes are required. VITA 41.4, VXS 4X PCI Express, passed a working group ballot in April also. It will be submitted to an ANSI ballot later in the year.

VITA 42 – Switched Mezzanine Card (XMC)
The XMC family of draft standards provides a method for implementing various serial/parallel fabric architectures on a PMC-like mezzanine module. The base level draft standard 42.0 defines the physical changes to the PMC module to support high-speed fabrics. Several dot level draft standards define the appropriate pin assignments for specific fabrics including parallel RapidIO, serial RapidIO, and PCI Express. At the March VSO meeting a new connector was proposed as a possible replacement for the current connector. The new connector would require less insertion/extraction force, but would not be mechanically interoperable with the current connector. The working group is reviewing the issues surrounding switching connectors and plans to make a decision in May.

VITA 46 – Advanced Module Format (Working Title)
The VITA 46 working group is developing a 3U/6U 160 mm deep module with a high-performance connector capable of supporting both high-speed parallel and serial fabrics for commercial and military environments. At the March VSO meeting the results of preliminary environmental tests were presented with no major issues being uncovered during the testing. The working group continues to work on the base level draft and anticipates it to go to a working group ballot in May.

The working group is focusing on Enhanced Ruggedized Design Implementation (ERDI). The goal of this draft standard is to define a general mechanical design implementation for circuit card assemblies that will enhance both their thermal performance and structural integrity. Randy Banton, working group chair, reported at the March meeting that the group had decided to focus on 0.85 and 1.0 interboard spacing. Additionally, he presented preliminary drawings of how liquid cooling could be implemented. Randy indicated that he plans to show prototypes at the next VSO meeting.

VITA 49 – Digital Intermediate Frequency (IF)
The goal of the VITA 49 working group is to develop a new interconnect standard for passing a radio’s digitized IF data between computer boards. The group is currently working on the packet framework. Their goal is to have a draft ready by the summer.

VITA 50 – Best Practices for Electronic Module Cooling
Rex Harvey, Parker Hannifin, led the working group in a discussion of a proposed outline for VITA 50 at the March VSO meeting. The group continues to discuss the scope of the effort and how to develop a realistic outline.

Table 1
(Click graphic to zoom)

. . . . .

John Rynearson is Technical Director of VITA. Previously, he founded Rystar, Inc. specializing in VMEbus training, and was one of the founders of Mizar, Inc., an early VMEbus company.

VITA – the VMEbus International Trade Association – was formed in 1984 to promote and enhance the VME standards, and to champion open standards in the embedded computing industry. VITA received accreditation as an ANSI-certified standards developer in 1993, and further received accreditation as an IEC-ITA certified standards developer in 2000.

For more information, contact John at:

P.O. Box 19658
Fountain Hills, AZ 85269
Tel: 480-837-7486
E-mail: techdir@vita.com
Website: www.vita.com