On Wed, Jan 13, 2016 at 5:24 AM, M. J. Everitt (m DOT j DOT everitt AT iee DOT org) [via geda-user AT delorie DOT com] <geda-user AT delorie DOT com> wrote:

On 12/01/16 17:19, Peter Clifton (petercjclifton AT googlemail DOT com) [via geda-user AT delorie DOT com] wrote:

On 12 Jan 2016 17:02, "Frank Miles (fpm AT u DOT washington DOT edu) [via geda-user AT delorie DOT com]" <geda-user AT delorie DOT com> wrote:
>

> Perhaps I'm confused. I thought I had read that the netlist import was
> deprecated, and that the proper way of importing the netlist was through
> PCB:File/Import Schematics. If netlist import is still equally valid,
> then please accept my apology for the needless noise.
>
> -F

The import mechanism was added as a more integrated way of retrieving this information, rather than relying on an external tool, gsch2pcb to process your existing design file and make edits. (This tool had to read and make edits to the board files, so represented a barrier to format changes. This was probably not the initial motivation of the new mechanism, but represents a big plus point to its existence).

Underlying the mechanism is a netlist backend for gnetlist which describes the components and nets of the design using a series of pcb action commands. These are executed by pcb on the open design, and in turn update the internal view of the netlist.

The "old" netlist format is not deprecated, although it does not convey all of the information about parts etc.. (gsch2pcb managed that aspect based upon a template file a separate gnetlist backend would populate with all the parts of a given design).

Since gsch2pcb and associated netlist backends were in a separate code base to pcb, this represented a compatibility problem if ever we changed things with the file format. The new backend lives with PCB (iirc), so merely relies on gnetlist keeping a stable scheme api and command line interface.

You might be interested to know that the update mechanism can be wired to call a makefile (or other scripts?) to generate the required data, so it is infact quite general. Only the "schematics" attributes are really assumed to come from a simple gschem work flow.

At some point, I may update xgsch2pcb to use this new mechanism, rather than gsch2pcb. It seems redundant to update gsch2pcb itself though.

Peter

I confess to never using the Import Schematics, probably because its only just appeared in the builds I have ready access to. I have never had any problems with the gsch2pcb workflow, like much of geda-gaf, it's quirky, but it works, and and you soon figure out how to make it do what is necessary.

It took me a long time to get around to trying it as well, for about the same reason. It's worth it though, especially if you find yourself making a lot of small changes on the gschem side and routing them incrementally.

Britton