[Author Prev][Author Next][Thread Prev][Thread Next][Author Index][Thread Index]
Re: gEDA-user: Light vs heavy gschem symbols?
Light vs. heavy is nomenclature which I just made up. Perhaps there
are other terms? If so, I don't know what they are. Anyway, this is
what I mean:
Gschem currently uses "light" symbols. That is, each symbol in the
symbol lib has almost no built-in attributes. It is up to the user
to place the symbol and then add all the attributes he needs manually,
either using gschem's attribute pop-up or perhaps using gattrib or an
By "heavy" symbol I mean that each symbol in the lib has a bunch of
attributes already attached to it. In this case, the user just sticks
the symbol into his design, and he is then ready to netlist without
further work. Particular attributes which users seem to want built
into the symbol include "footprint", and spice models. Protel is an
example of an EDA system with "heavy" footprints.
The reason for the discussion is that we constantly hear reports from
newbies that they want better integration between gschem and PCB. A
common complaint involves the fact that newbies don't want to -- or
don't know how to -- stick PCB footprint names onto the symbols while
creating their schematics. I just got a few more in my in-box last
week, which triggered my Free Dog suggestion.
It is true that it is not a priori clear what footprint names to stick
into symbols until you have had some experience with PCB. Nowhere in
any documentation does it tell you what footprint names go with which
parts. Indeed, if you use the M4 footprints you've got to look
through the files themselves to find the footprint names. The newlib
footprints are a little better since the footprint name is the file
name. Nonetheless, newbies are often thrown for a loop when it comes
to putting footprint attributes into the schematic. This is the
reason I bring the subject up.
Personally, I like gschem's attribute mechanism just the way it is.
"Light" footprints provide maximum flexibility to users who know what
they are doing. Moreover, bulk managing footprints is easy using
gattrib. On the other hand, Ales had some good ideas about how to
further simplify the selection of footprint attribs. I thought I
would share with the teeming Free Dog multitudes a couple of my recent
e-mails from newbies complaining about footprint attributing. Then
perhaps we would talk more about various improvements one might make
to gschem which would be lightweight, but might also make it easier
for newbies to attribute their designs.
> Could you give us a brief discussion on light vs. heavy gschem symbols?
> Steve Meier
> Stuart Brorson wrote:
> >-------------- Free Dog Gathering Announcement ----------------
> >The Free EDA Users Group will meet this coming Thursday, June 2nd.
> >Once again, let's meet at the Starbucks across the street from Quantum
> >Books on Ames St, between Main St and Broadway. It's about 1 block
> >away from the Kendall Sq "T" stop. (In Cambridge, MA, USA, of
> >The meeting will be an open and informal working session. Bring your
> >laptop! Some items on the agenda are:
> >* Scilab vs. Octave showdown! (by request)
> >* More discussion about "light" vs. "heavy" gschem symbols.
> >* Your favorite issue here!
> >Free Dog is an association of like-minded hackers and engineers
> >interested in free and open EDA tools. We hold monthly meetings at MIT
> >(and other locations) featuring informal networking, speakers, and
> >camaraderie. Our goals are to learn more about CAD, engineering and
> >scientific software, share ideas about our current projects, and --
> >most importantly -- have fun with like-minded people. We welcome new
> >members and participants of all ages. Students are particularly
> >Date: Thursday, June 2nd, 2005. (*** Note the change of day! ***)
> >Time: 7:00pm
> >Location: Starbucks Coffee, 6 Cambridge Center, Cambridge,
> >MA, USA.
> >For more details, please contact me privately at sdb (AT) cloud9 (DOT)