1364: 5.6.6 Port connections

From: Shalom Bresticker (Shalom.Bresticker@motorola.com)
Date: Mon Oct 15 2001 - 06:48:45 PDT

I have a question:

5.6.6 says that
"Ports connect processes through implicit continuous assignment statements or implicit bidirectional connections ...
Ports can always be represented as declared objects connected as follows:
If an input port, then a continuous assignment from an outside expression to a local (input) net ..."

Regarding strengths of continuous assignments, 6.1.4 says, at the end,
"If drive strength is not specified, it shall default to (strong1, strong0)."

If I put these two sections together, it implies that an input port will always be strong.

However, we know and see that this is not so.
That is, if I drive a net weakly and connect it to an input port of another module,
that input port will also have a weak strength.

I attach an example.

Explanations ? 

--
**************************************************************************
Shalom Bresticker                           Shalom.Bresticker@motorola.com
Motorola Semiconductor Israel, Ltd.                  Tel #: +972 9 9522268
P.O.B. 2208, Herzlia 46120, ISRAEL                   Fax #: +972 9 9522890
**************************************************************************

<p><p><p>

module test;

tri1 aa ;
reg bb ;

assign (pull1, pull0) aa = bb ;

initial 
begin
#5
	bb = 1'bz ;
#5
	$display (aa,,bb) ;
#5
	bb = 1'b0 ;
#5

	$display (aa,,bb) ;

end
endmodule // test

This archive was generated by hypermail 2.1.4 : Mon Jul 08 2002 - 12:54:47 PDT and
sponsored by Boyd Technology, Inc.