IEEE-1076-2008.pdf

IEEE Std 1076-2008 (Revision of IEEE Std 1076-2002) IEEE Standard VHDL Language Reference Manual IEEE 3 Park Avenue New York, NY 10016-5997, USA 26 January 2009 IEEE Computer Society Sponsored by the Design Automation Standards Committee 1076 TM Copyright The Institute of Electrical and Electronics Engineers, Inc. Provided by IHS under license with IEEELicensee=HP Monitoring/1111111164 Not for Resale, 04/06/2009 01:42:04 MDTNo reproduction or networking permitted without license from IHS -,-,- Copyright The Institute of Electrical and Electronics Engineers, Inc. Provided by IHS under license with IEEELicensee=HP Monitoring/1111111164 Not for Resale, 04/06/2009 01:42:04 MDTNo reproduction or networking permitted without license from IHS -,-,- IEEE Std 1076-2008 (Revision of IEEE Std 1076-2002) ? IEEE Standard VHDL Language Reference Manual Sponsor Design Automation Standards Committee? of the? IEEE Computer Society Approved 26 September 2008? IEEE SA-Standards Board Copyright The Institute of Electrical and Electronics Engineers, Inc. Provided by IHS under license with IEEELicensee=HP Monitoring/1111111164 Not for Resale, 04/06/2009 01:42:04 MDTNo reproduction or networking permitted without license from IHS -,-,- The Institute of Electrical and Electronics Engineers, Inc. 3 Park Avenue, New York, NY 10016-5997, USA Copyright © 2009 by the Institute of Electrical and Electronics Engineers, Inc. All rights reserved. Published 26 January 2009. Printed in the United States of America. IEEE and POSIX are registered trademarks in the U.S. Patent the communication of hardware design data; and the maintenance, modification, and procurement of hardware. Its primary audiences are the implementors of tools supporting the language and the advanced users of the language. Keywords: computer languages, electronic systems, hardware, hardware design, VHDL Copyright The Institute of Electrical and Electronics Engineers, Inc. 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Introduction The VHSIC Hardware Description Language (VHDL) is a formal notation intended for use in all phases of the creation of electronic systems. Because it is both machine readable and human readable, it supports the development, verification, synthesis, and testing of hardware designs; the communication of hardware design data; and the maintenance, modification, and procurement of hardware. This document, IEEE Std 1076-2008, is a revision of IEEE Std 1076-2002 as amended by IEEEStd1076cTM-2007. Initial work on gathering requirements and developing language extensions was undertaken by the IEEE VHDL Analysis and Standardization Group (VASG), otherwise known as the 1076 Working Group. Subsequently, Accelleraa sponsored an effort to complete that work and draft a revised Language Reference Manual. That draft was returned to IEEE for final revision and approval, resulting in this document and the associated machine-readable files. This revision incorporates numerous enhancements, both major and minor, to previously existing language feaures and several new language features. The changes are summarized in Annex E. In addition, several VHDL library packages that were previously defined in separate standards are now defined in this standard, ensuring that they are treated as integral parts of the language. Finally, this revision incorporates the IEEE Property Specification Language (PSL) as part of VHDL. The combination of these changes significantly improves VHDL as a language for specification, design, and verification of complex electronic systems. The maintenance of the VHDL language standard is an ongoing process. The chair of the VHDL Analysis and Standardization Group extends his gratitude to all who have participated in this revision, both in the IEEE committees and the Accellera effort, and encourages the participation of all interested parties in future language revisions.b Notice to users Laws and regulations Users of these documents should consult all applicable laws and regulations. Compliance with the provisions of this standard does not imply compliance to any applicable regulatory requirements. Implementers of the standard are responsible for observing or referring to the applicable regulatory requirements. IEEE does not, by the publication of its standards, intend to urge action that is not in compliance with applicable laws, and these documents may not be construed as doing so. Copyrights This document is copyrighted by the IEEE. It is made available for a wide variety of both public and private uses. These include both use, by reference, in laws and regulations, and use in private self-regulation, standardization, and the promotion of engineering practices and methods. By making this document available for use and adoption by public authorities and private users, the IEEE does not waive any rights in copyright to this document. aMore information is available at www.accellera.org. bIf interested in participating, please contact the VASG at stds-vasgieee.org or visit: http:/www.eda.org/vasg. This introduction is not part of IEEE Std 1076-2008, IEEE Standard VHDL Language Reference Manual. Copyright The Institute of Electrical and Electronics Engineers, Inc. Provided by IHS under license with IEEELicensee=HP Monitoring/1111111164 Not for Resale, 04/06/2009 01:42:04 MDTNo reproduction or networking permitted without license from IHS -,-,- Copyright © 2009 IEEE. 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Participants At the time this standard was submitted to the IEEE-SA Standards Board for approval, the 1076 Working Group had the following membership: Jim Lewis, Chair Chuck Swart, Vice Chair Peter Ashenden, Secretary and Technical Editor John Aynsley Stephen Bailey Victor Berman Patrick Bryant Roland R. Henrie Daniel Kho Françoise Martinolle Egert Molenkamp Robert Myers Farrell Ostler John Ries Timothy Schneider Sukrit Shankar John Shields Alain Vachoux Ajayharsh Varikat Richard Wallace John Willis Alex Zamfirescu Mark Zwolinski Copyright The Institute of Electrical and Electronics Engineers, Inc. Provided by IHS under license with IEEELicensee=HP Monitoring/1111111164 Not for Resale, 04/06/2009 01:42:04 MDTNo reproduction or networking permitted without license from IHS -,-,- viCopyright © 2009 IEEE. All rights reserved. The following members of the individual balloting committee voted on this standard. Balloters may have voted for approval, disapproval, or abstention. When the IEEE-SA Standards Board approved this standard on 26 September 2008, it had the following membership: Robert M. Grow, Chair Thomas Prevost, Vice Chair Steve M. Mills, Past Chair Judith Gorman, Secretary *Member Emeritus Also included are the following nonvoting IEEE-SA Standards Board liaisons: Satish K. Aggarwal, NRC Representative Michael Janezic, NIST Representative Jennie Steinhagen IEEE Standards Program Manager, Document Development Michael D. Kipness IEEE Standards Program Manager, Technical Program Development Peter Ashenden Bakul Banerjee Victor Berman Martin J. Bishop Lyle Bullock James Case Keith Chow Ernst Christen S. Claassen Kevin Coggins Joanne Degroat Thomas Dineen Steven Dovich George Economakos Charles Gardiner Sergiu Goma Randall Groves William Hanna M. Hashmi Werner Hoelzl Joseph Hupcey Piotr Karocki Kurt Kermes Jim Lewis G. Luri Timothy McBrayer Donald Mills Egbert Molenkamp Robert Myers Prajit Nair Z. Navabi Michael S. Newman Ulrich Pohl Bartien Sayogo Timothy Schneider Stephen Schwarm John Sheppard John Shields David Smith Walter Struppler Chuck Swart Lance Thompson Yatin Trivedi Alain Vachoux Ajayharsh Varikat Srinivasa Vemuru Kathy Werner John Willis Paul Work