Re: [vhdl-200x] Switch model

From: Jim Lewis <Jim@synthworks.com>
Date: Mon Mar 10 2014 - 10:41:17 PDT
HI Jakko,
I would particularly be interested in seeing an example and hardware picture of something that requires conditional usage of this.

I would more likely call it a switch or attachment operation. Calling it an assignment is going to make people want to inject delta cycles - which is not going to work.

Jim



> Hi Brent,
>
>
> What you actually want is a bidirectional assignment (for any resolved type).
>
> The problem with the code you listed below, is that you cannot have 2 of those assignments in a row, it will lead to wrong results.
>
> If you could assign 2 ways (like tran or tranif), then the problem is solved.
>
> I'd like to see something like
>
> a <=> b [when c else 'Z'];
>
> This would ease multiport wires with bidirectional (and conditional) assignments.
>
> Jakko


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Received on Mon Mar 10 10:41:15 2014

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