gEDA-dev: gEDA-user: PCB layout for identical units?

[John Doty]

On Sep 21, 2007, at 12:51 PM, Stefan Salewski wrote:

> Hello,
>
> I am designing a device which has two identical units, like the
> amplifiers in a stereo audio device. Other parts, like power supply
> exists only once.
>
> I think I can draw a schematics of one unit, make a copy, rename  
> devices
> in that copy and have both units. (The other common parts are  
> contained
> in separate schematics.)
>
> If I now use gsch2pcb to generate the initial pcb board, then I  
> have to
> do the layout for each of the two identical units.
>
> Is there a way to do the layout for only one unit, then copy this  
> part,
> rename components and have both units?

An interesting request, related to hierarchy. Right now, if you do a  
hierarchical design, the gnetlist back ends produce a flat netlist.  
Is there a way to get a hierarchical netlist? Are there hooks I don't  
know about in gnetlist, so a back end can see the hierarchy?

For chip design, I assemble hierarchical netlists from subcircuit  
netlists using a makefile rule. This means I can't use the source=  
attribute, so the hierarchy commands in gschem don't work. But this  
is essential for chip design, as then the layout designer then need  
only lay out each cell once. My recent ~7000 component chip design  
contains 45 types of cells. A cell contains an average of 8  
components, the majority of which are subcells. That's an enormous  
simplification.

Wouldn't it be cool to have PCB understand a hierarchical net list,  
and gnetlist able to generate one, so board designers could work with  
cells like chip designers, and chip designers could fully exploit  
gschem's hierarchy commands?

John Doty              Noqsi Aerospace, Ltd.
http://www.noqsi.com/
jpd at noqsi.com