hi BC, EC, On a number of previous occasions I've nagged away at the issue of what it really means to have a modport with an item of "output" direction, without getting a definitive result. Synthesis implementors strongly take the position that it represents a continuous assignment to the corresponding interface item, but the LRM does not really justify this and all the major simulators take the other position, that the modport-type port represents an alias to the modport instance. The consequences of this divergence are unpleasant. I have created Mantis 2114 to ask for clarification. As I hope I've made clear in the bugnote, clarifying the LRM in the synthesis implementors' favour would severely impact the usability of interfaces and modports by outlawing some obvious idioms, including certain uses of virtual interface (which is why EC is copied, although I've marked the Mantis for BC since they are primarily responsible for interfaces). I am convinced that this is quite badly broken, and needs fixing. Unless someone can persuade me otherwise, I urge BC to take a look at this and get it on to their agenda if at all possible. I'm happy to do the legwork of writing a proposal if people can tell me what the consensus is. Thanks -- 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 The contents of 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 Oct 16 14:26:31 2007
This archive was generated by hypermail 2.1.8 : Tue Oct 16 2007 - 14:26:45 PDT