DJ Delorie wrote: > Way back when, when I use cadstar, what they did was have multiple > alternatives within each symbol and footprint. So, the mapping was > generic part -> generic symbol -> alternative, and generic part -> > specific part -> footprint. ...
That is what most CAD systems do. Usually you can't select farther down than footprint, like "oh, I want one with the solder mask tucked some more". That would require making a new footprint with a new name to it. Then in programs like Eagle this new footprint must also be assigned to a part or it won't show up in the footprint selector for that part. > ... This thread makes me think we need to > allow for footprint alternatives in pcb, so it would be: > > generic symbol -> alternatives (positive vs negative logic, orientation, > design, etc) > > generic symbol -> generic part > > generic part -> specific parts (manufacturer?) > (note: this does symbolic pins -> numbered pins too) > > specific part -> slotting(grouping) -> gschem (this is done in gschem) > specific part -> footprint class -> specific footprint > > specific part -> vendor, costs, inventory, etc. > This would be leather seats plus champagne cooler :-) > footprint class (or specific) -> slotting(numbering) -> gschem (this is done > in pcb) > That part would IMHO only make sense if or after the broken annotation and power pin issue gets resolved. > For SOP footprints, for example, we could "outline around pads" and > "outline between pads" options, or project-specific alternatives like > "extra clearance". > Nice, but it doesn't have to go that far. Most people are used to making special footprints. Like one for Rogers, one for FR4 and maybe one for <gasp> the super-saver phenolic projects, then keep using them all the time. When I ask my layouter to make a change because of high voltage or something he just creates a whole new footprint and calls it joerg_d2pak or whatever. It doesn't consume much of his time because he cuts and pastes from the standard one. -- Regards, Joerg http://www.analogconsultants.com/ _______________________________________________ geda-user mailing list [email protected] http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
