The USB 1.1 spec now includes one Engineering Change Notice which is included in this zip file. This document was approved on 11/23/99 by the USB Core team. Any design work with the USB 1.1 spec should give equal consideration to this ECN document and the spec. You must have Adobe Acrobat Reader 3.0 or better to read them. You may download a free copy of the Adobe Acrobat Reader from the Adobe website at www.adobe.com