IEEE 1076-2011 en Behavioural languages C Part 1-1 VHDL Language Reference Manual (IEEE Computer Society)《行为语言 第1-1部分 VDHL语言参考手册(IEEE计算机协会)》.pdf

1、 IEC 61691-1-1 Edition 2.0 2011-0g24 INTERNATIONAL STANDARD Behavioural languages Part 1-1: VHDL Language Reference Manual IEC 61691-1-1:2011(E)IEEE Std1076-2008IEEE Std 1076THIS PUBLICATION IS COPYRIGHT PROTECTED Copyright 2008 IEEE All rights reserved. IEEE is a registered trademark in the U.S. Pa

2、tent any IEC National Committee interested in the subject dealt with may participate in this preparatory work. International, governmental and non-governmental organizations liaising with the IEC also participate in this preparation. IEC collaborates closely with the International Organization for S

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7、reas, access to IEC marks of conformity. IEC is not responsible for any services carried out by independent certification bodies.6) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of patent rights. IEC shall not be held responsible for ident

8、ifying any or all such patent rights.International Standard IEC 61691-1-1/IEEE Std 1076 has been processed through IEC technical committee 93: Design automation.This second edition cancels and replaces the first edition published in 2004. This edition constitutes a technical revision.The text of thi

9、s standard is based on the following documents:g3Full information on the voting for the approval of this standard can be found in the report on voting indicated in the above table.IEEE Std FDIS Report on voting1076 (2008) 93/302/FDIS 93/304/RVDIEC 61691-1-1:2011(E) - viii - g3IEEE Std 1076-2008Publi

10、shed by IEC under license from IEEE. 2008 IEEE. All rights reserved.A list of parts of the IEC 61691 series can be found on the IEC website.The committee has decided that the contents of this publication will remain unchanged until the stability date indicated on the IEC web site under “http:/websto

11、re.iec.ch“ in the data related to the specific publication. At this date, the publication will be reconfirmed, withdrawn, replaced by a revised edition, or amended.- ix - IEC 61691-1-1:2011(E)g3IEEE Std 1076-2008Published by IEC under license from IEEE. 2008 IEEE. All rights reserved.IEC/IEEE Dual L

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29、er.NOTE Attention is called to the possibility that implementation of this standard may require use of subject matter covered by patent rights. By publication of this standard, no position is taken with respect to the existence or validity of any patent rights in connection therewith. The IEEE shall

30、 not be responsible for identifying patents for which a license may be required by an IEEE standard or for conducting inquiries into the legal validity or scope of those patents that are brought to its attention.IEC 61691-1-1:2011(E) - x - g3IEEE Std 1076-2008Published by IEC under license from IEEE

31、. 2008 IEEE. All rights reserved.- xi - IEC 61691-1-1:2011(E)g3IEEE Std 1076-2008Published by IEC under license from IEEE. 2008 IEEE. All rights reserved.g3IEEE Standard VHDL Language Reference ManualSponsor Design Automation Standards Committeeg3of theg3IEEE Computer SocietyApproved 26 September 20

32、08g3IEEE SA-Standards BoardIEEE 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

33、language.Keywords: computer languages, electronic systems, hardware, hardware design, VHDL- xiii - IEC 61691-1-1:2011(E)g3IEEE Std 1076-2008Published by IEC under license from IEEE. 2008 IEEE. All rights reserved.IEEE introductiong3The VHSIC Hardware Description Language (VHDL) is a formal notation

34、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 procu

35、rement of hardware.This document, IEEE Std 1076-2008, is a revision of IEEE Std 1076-2002 as amended by IEEE Std 1076cTM-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 1

36、076 Working Group. Subsequently, Accelleraasponsored 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 numero

37、us 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

38、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

39、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 part

40、ies in future language revisions.bNotice to usersLaws and regulationsUsers 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 resp

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43、ption 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.IEC 61691-1-1:2011(E) -

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47、ment process, visit the IEEE-SA website at http:/standards.ieee.org.ErrataErrata, if any, for this and all other standards can be accessed at the following URL: http:/standards.ieee.org/reading/ieee/updates/errata/index.html. Users are encouraged to check this URL for errata periodically.Interpretat

48、ionsCurrent interpretations can be accessed at the following URL: http:/standards.ieee.org/reading/ieee/interp/index.html.PatentsAttention is called to the possibility that implementation of this standard may require use of subject matter covered by patent rights. By publication of this standard, no

49、 position is taken with respect to the existence or validity of any patent rights in connection therewith. The IEEE shall not be responsible for identifying patents or patent applications for which a license may be required to implement an IEEE standard or for conducting inquiries into the legal validity or scope of those patents that are brought to its attention.IMPORTANT NOTICE: This standard is not intended to assure safety, security, health, or environmental protection in all circumstances. Implementers of the standard are responsible for determining app