> >the modport expression .P(E) says "when a module > >connects its port "portname" to this modport in > >some instance of interface I, the module's item > >portname.P should be connected not to the internal > >object P of the connected interface instance, but > >instead to the expression E in that instance". > > This description suggests that there is an item > portname.P inside the module, that is connected to E > in the interface instance. I don't view it that way. Yes, my wording was a little careless. I agree (or, at least, I think I agree: see later) that there is no "portname.P" inside the connected module. I should have said something like any reference to portname.P inside the module should denote not an item P in the interface instance, but the expression E in that instance. This is not merely hair-splitting. One of the things I most want to see in a future PAR is an effort to rewrite the whole interfaces clause so that it is unambiguous and complete. Clarification of the intent is an important first step. There have been extensive discussions here and elsewhere concerning a module driving something in an interface through a modport item whose direction is output. The general conclusion seems to be that such a connection should be regarded as a continuous assignment from the module to the thing in the interface, although tools don't follow this model at present. For this to work, I believe, it may in some cases be necessary to create an implicit variable portname.P inside the module. -- Jonathan Bromley Consultant DOULOS - Developing Design Know-how VHDL * Verilog * SystemC * e * Perl * Tcl/Tk * Project Services Doulos Ltd. Church Hatch, 22 Market Place, Ringwood, Hampshire, BH24 1AW, UK Tel: +44 (0)1425 471223 Email: jonathan.bromley@doulos.com Fax: +44 (0)1425 471573 Web: http://www.doulos.com This message may contain personal views which are not the views of Doulos Ltd., unless specifically stated. -- This message has been scanned for viruses and dangerous content by MailScanner, and is believed to be clean.Received on Tue Dec 2 01:22:50 2008
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