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Re: gEDA-user: Power nets in hierarchy

Stuart Brorson wrote:


Why not just define an attribute "GLOBAL" which you could attach to a
net?  A global net would then have two attributes: NETNAME and GLOBAL,
for example:

NETNAME=VCC
GLOBAL=1

Then the netlister would know directly what type of net it was
handling, instead of having to figure it out from the attached
schematic symbol.  In any event, I often just use named nets for power
instead of attaching a power symbol.  Finally, there are other common
nets which aren't power nets but are also globals, such as RESET.
Nets like RESET don't always have an accepted device symbol.

Stuart
I like the GLOBAL concept. How does this class diagram (schema) look? I've added a Global class on Design to represent global signals. I think this will lead to easy manipulation of these things.

For example, after flattening, I might still have a bunch of small nets that are all attached to a common global. A global net flatting routing could replace them all with a single net. Another routine could be used to thread the global signals through the hierarchy in case a netlist format doesn't support globals.

I think POWER device types could also be useful. It's just another way to do the same thing, but in a way that feels familiar and looks good in a schematic.

Bill

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