MARCH 21--The PCI Industrial Computers Manufacturers Group (PICMG; Wakefield, MA) has published two new documents--the PICMG 1.2 Embedded PCI-X (ePCI-X) specification for standard form-factor PCI and an Engineering Change Notice, ECN 002, to the PICMG 2.0 CompactPCI form-factor core specification on the topic of self-describing slot geography. The new PICMG 1.2 specification standardizes the mechanical and electrical interface to support a standard form-factor PCI computer system with either two PCI/PCI-X buses or a single PCI/PCI-X bus. The document also defines the electrical and mechanical connections for a single board computer and backplane. This ePCI-X is an evolutionary modification of the PICMG 1.0 PCI-ISA Specification; PCI-X capabilities are added to the PCI bus, and the ISA bus is replaced by a second PCI-X bus. The board retains the same mechanical dimensions as PCI-ISA but the components move to the PCI side and the slot occupies a PCI position on a backplane.
The focus of the ECN to PICMG 2.0 is to enable hardware-independent software to map between the geographic addresses of CompactPCI slots and the logical PCI addresses by which operating systems and device drivers access the boards in those slots. The emphasis is on systems containing CompactPCI buses on the backplane. This logical to geographical mapping further improves the already robust system management capabilities of CompactPCI by allowing management applications to correlate faults reported through system-management infrastructure and hot-swap events reported directly through the operating system.
"The adoption of PICMG 1.2 demonstrates that there is an evolving market for passive backplane products using standard form-factor PCI and PCI-X options," said Dick Somes of Force Computers, PICMG technical officer. "The ECN addresses a long-standing issue that has faced the CompactPCI community since the adoption of PICMG 2.9, the System Management specification, and it is an important step in completing the CompactPCI architecture defined by the PICMG 2 series of specifications."
The PICMG 1.2 technical subcommittee was chaired by Jan-Philippe DeBroeck of Kontron, and the ECN effort was led by Mark Overgaard of Pigeon Point Systems. The documents were approved by the PICMG executive membership in January. They are currently being distributed to PICMG members in good standing and are available for purchase by nonmembers from the PICMG Web site: www.picmg.org. A list of the companies who participated in the technical subcommittee is included in each document.
