X-bit labs

PCI Gets Version Upgrade.

Category: Other

by Anton Shilov

[ 04/26/2004 | 06:50 AM ]

PCI-SIG delivered yet another specification of conventional PCI bus that has been around for over a decade already. The new revision does not bring any speed boosts to the standard, but only continues some evolutionary ideas of the previous versions.

The PCI-SIG, also known as the Special Interest Group responsible for Conventional PCI, PCI-X, and PCI Express industry-standard I/O technologies quietly released version 3.0 of the Conventional PCI specification. Revision 3.0 is the latest version of the Conventional PCI specification that builds upon version 2.3 and completes the migration of the PCI bus from the original 5.0V (volt) signaling to 3.3V-only slots.

As semiconductor signaling technologies have progressed since the 1992 release of the Conventional PCI 1.0 spec, the base signaling voltages have dropped from the standard of 5.0V to the current 3.3V. Subsequent Conventional PCI specifications, versions 2.0 and 2.3, responded to industry needs by first enabling 3.3V and then initiating the migration to 3.3V-only slots.

The new Conventional PCI 3.0 spec completes the migration to 3.3V-only slots by removing support for 5.0V-only keyed add-in cards. Universal keyed add-in cards (cards that are keyed for both 5.0V and 3.3V slots) continue to be supported by the Conventional PCI 3.0 spec. Version 3.0 also incorporates the errata and ECNs (Engineering Change Notifications) to version 2.3 specification. Version 3.0 supports multiple bus specifications: PCI 66, PCI-X, Mini PCI, and Low Profile PCI.

It was not said who would support the new standard by core-logic components as well as add-in cards.

Contribution the PCI-SIG made to the PCI standard is exceptional, but the 3.0 spec is likely to become the last and final version of the standard, as this year the PCI Express bus emerges to eventually succeed the PCI.