Re: current signal-flow discipline

Marq,

What happens when you connect a signal-flow port to a conservative 
discipline. From what i understand, this should be fine (as per today's 
LRM standard) as long as the potential nature of the signal-flow matches 
with the conservative discipline.

I am not sure whether the above is explicitly specified in the LRM? If 
not, i guess it needs to be clarified if the above approach is correct. 
Also in the same vein i guess for a signal-flow with only flow nature 
the flow nature should match with the conservative discipline.

cheers,
Sri



Marq Kole wrote:
> Hi Sri,
> 
> I've checked the email reflector. Clause 3.6.2.1 is OK as per Mantis 
> item 1405, as discussed in an email exchange between Graham Helwig and 
> Ken Kundert from May 1st, 2006. To summarize: the original Verilog-A 1.0 
> supported both potential-only and flow-only signal flow disciplines. 
> This has been restricted to potential-only signal-flow disciplines in 
> later versions of the standard for unknown reasons. Mantis item 1405 
> requests to remove the restriction on potential-only signal-flow 
> disciplines and that is what the example in Clause 3.6.2.1 refers to.
> 
> Essentially, LRM 2.3 Draft 2 has partially implemented this Mantis item. 
> Section 1.3.3 should be updated to support also flow-only signal-flow 
> disciplines. Section 1.3.4 does not contradict this, so no change would 
> be needed there. Section 1.3.4 could be extended with the notion that 
> multiple flow-only sources can be connected together to attach to a 
> single sink, but this explanation may be postponed to a later release if 
> needed. However, another consequence would also be to update the 
> "disciplines.vams" file to reflect this situation, in particular the 
> "current" discipline should be made into a flow-only discipline. I think 
> the latter is an important item.
> 
> Best regards,
> Marq
> 
> owner-verilog-ams@server.eda.org wrote on 31-01-2008 09:07:40:
>  > Marq,
>  >
>  > Is clause 3.6.2.1 in error? For signal-flow disciplines the nature has
>  > to be potential. Current contributions on these nodes are not legal as
>  > the flow nature is not defined for signal-flow systems. There is a
>  > reference made to this in clause 1.3.3 also and the details for
>  > signal-flow is given in clause 1.3.4
>  >
>  > cheers,
>  > Sri
>  >
>  > Marq Kole wrote:
>  > > Hi All,
>  > >
>  > > The current draft 2 contains an ambiguity: in section 3.6.2.1 on 
> Nature
>  > > Binding an example signal-flow discipline show the current discipline
>  > > with a flow nature, while Annex D.1 shows that in the disciplines.vams
>  > > the current discipline still has a potential nature. In my opinion for
>  > > Verilog-AMS 2.3 the disciplines.vams should be updated to make the
>  > > current discipline have a flow nature.
>  > >
>  > > Currently, in Verilog-AMS 2.2 a module with terminals that have a
>  > > signal-flow nature of current cannot be connected to a net of 
> discipline
>  > > electrical and assume that the current in one connects to the 
> current in
>  > > the other. With the above change this should be resolved.
>  > >
>  > > Cheers,
>  > > Marq
>  > >
>  > > --
>  > > This message has been scanned for viruses and
>  > > dangerous content by *MailScanner* <http://www.mailscanner.info/>, 
> and is
>  > > believed to be clean.
>  > >
>  >
>  > --
>  > Srikanth Chandrasekaran
>  > Design Technology (Tools Development)
>  > Freescale Semiconductor Inc.
>  > T:+91-120-439 5000 p:x3824 f: x5199
>  >
>  > --
>  > This message has been scanned for viruses and
>  > dangerous content by MailScanner, and is
>  > believed to be clean.
>  >
> 
> -- 
> This message has been scanned for viruses and
> dangerous content by *MailScanner* <http://www.mailscanner.info/>, and is
> believed to be clean.
> 

-- 
Srikanth Chandrasekaran
Design Technology (Tools Development)
Freescale Semiconductor Inc.
T:+91-120-439 5000 p:x3824 f: x5199

-- 
This message has been scanned for viruses and
dangerous content by MailScanner, and is
believed to be clean.