Intel standardises USB host interface

Electronics Times, Jan 15, 2001

Intel has released its universal serial bus (USB) 2.0 enhanced host controller interface specification. The specification standardises the interface between the host controller and its software driver. Despite being launched more than 18 months ago, companies are still working on issues such as compatibility.

USB 2.0 is designed to enhance the performance of PC peripherals, such as mice, keyboards, printers and scanners. The interface can operate up to 480Mbit/s. The current standard, USB 1.1 operates at 12Mbit/s.

Intel developed the specification in collaboration with NEC, Philips, Lucent, Microsoft and Compaq. It intends to licence it on a royalty free basis.

"During the development of USB 1.0, the existence of two versions of host controller interface specs made it more difficult for OS vendors to develop software support for multiple implementations of host controllers in the industry," says an Intel technical bulletin.

"For USB 2.0, Intel's goal was to develop one specification the entire industry would use, increasing compatibility of the various implementations and making it easier to develop software support."

During the development of 2.0, Intel maintained control of the intellectual property associated with the main PC interface but it will licence it free.

Philips' USB marketing manager, Rajeev Mehtani, said that the faster data rates possible with 2.0 will make products such as smart cards more user friendly. To download 2.5Mbyte of data from a smart card will take 2.5s..

Testing of products to ensure they are compatible is a crucial issue for developing 2.0.

"Two different companies' products need to be able to talk to each other," he said. "The development group has set up compliance workgroups to set standards and workshops to ensure products are compatible before receiving 2.0 certification."

According to Thibault Brunet, marketing manager for USB microcontrollers at STMicroelectronics, the main issue is whether PCs with USB 2.0 ports will be compatible with USB 1.1 peripherals.

"In the past we have had experiences with USB 1.1 hosts that were out of specification," he said. "It is very important for us to really test this specification."

Brunet anticipates that within a year most PCs on the market will operate with USB 2.0 but the peripherals will probably take two years or more to establish.

Copyright: United Business Media Ltd.