RE: [vhdl-200x-ft] FT27: optional architectures

Thanks for catching this. The proposed additions look good.

-Steve Bailey

> -----Original Message-----
> Folks,
>
> Proposal FT27 specifies that architecture bodies be optional
> for design entities, and that entities can include arbitrary
> block declarations and statements. However, the proposal
> does not say how to revise configuration declarations to take
> account of the changes to entities and architectures.
>
> Currently, a configuration declaration includes block
> configurations that name architecture bodies. Such a block
> configuration represents the external block denoted by a
> design entity, either one identified by the configuration
> declaration or one bound to a component instance.
>
> With the proposed change, an external block may be denoted by
> an entity alone. We need to provide a way of specifying in a
> binding indication that no architecture body be used (even if
> there is one available), and a way of specifying a block
> configuration for the denoted external block.
>
> My suggestion is to use the reserved word "open" in place of
> an architecture name. Thus, the syntax rule for
> block_specification in page 13 would be revised to:
>
> block_specification ::=
> architecture_name
> | open
> | block_statement_label
> | generate_statement_label [ ( index_specification ) ]
>
> Also, the syntax rule for entity_aspect on page 81 would be
> revised to:
>
> entity_aspect ::=
> entity entity_name [ ( architecture_identifier | open ) ]
> | configuration configuration_name
> | open
>
> I'd also suggest revising the default binding rules to
> specify that the architecture to use is the most recently
> analyzed, if one exists, or none otherwise; and that the rule
> specifying that it be an error if no architecture exists be deleted.
>
> Comments?
>
> Cheers,
>
> PA
>
> --
> Dr. Peter J. Ashenden peter@ashenden.com.au
> Ashenden Designs Pty. Ltd. www.ashenden.com.au
> PO Box 640 Ph: +61 8 8339 7532
> Stirling, SA 5152 Fax: +61 8 8339 2616
> Australia Mobile: +61 414 70 9106
>
>
>
Received on Sun Dec 12 07:12:10 2004