Re: Verilog-AMS Committee Meeting Minutes - Dec 22 2006

From: Kevin Cameron <kevin_at_.....>
Date: Wed Jan 03 2007 - 15:26:29 PST
Dave Miller wrote:
> Hi Kevin
>> ....
>>
>> IMO you should be able to describe your design without connecting any 
>> ports and just wire it all up with OOMRs and it should behave the same.
>>
> Okay so you are saying that out of module reference V(top.a,top.b) is 
> simply creating a new unnamed branch between ckt nodes a, and b. This 
> branch will be in parallel to any unamed branches between (a,b) that 
> exist in module top. I was of the understanding that out of module 
> reference had to reference a pre-existing branch. If that's not the 
> case then I understand how this all works. This then means that you 
> can only ever have a switch branch that can possibly switch from 
> potential to flow in the same instance.
Same analog block (rather than instance),  that would be my 
understanding, but the LRM may not be saying that.
> But then I have to wonder what happens if instead of unnamed branches, 
> the user tries to contribute to a named branch using an out of module 
> reference. Surely this then would mean it is accessing the same branch 
> (not creating one in parallel) and hence all the problems I was 
> discussing above become an issue since order that instances are 
> evaluated can change results. Or would this also be a separate branch?
I think we have two distinct meanings for "branch", one is the syntactic 
declaration of a node-pair, the other is the "mathematical" one in the 
matrix used to solve the circuit. The latter is just the contribution 
from a particular analog block to a node-pair. We might want consider 
rewording some of the LRM to make it clearer.

Kev.
>
> Dave
>> Kev.
>>
>>>
>>> Dave
>>>
>>
>>
>
>

-- 
This message has been scanned for viruses and
dangerous content by MailScanner, and is
believed to be clean.
Received on Wed Jan 3 15:26:56 2007

This archive was generated by hypermail 2.1.8 : Wed Jan 03 2007 - 15:27:16 PST