On Mon, Sep 06, 2010 at 04:49:32PM -0400, DJ Delorie wrote: > > > Why have any distinction between "footprint" and other fragments of > > layout (like hierarchical blocks)? > > Because PCB needs to deal with boards at the semantic level, not just > the physical level. Padstacks have to "exist" at the element level so > they can be tied to the netlist, for example. A padstack elsewhere > has to be managed differently. >
We can store mappings in the file, though. Suppose I've got a footprint containing one element, U?, with 4 pads, P1 P2 P3 and P4. If I then bring the footprint into a pcb layout, the file would look like: element: U5 mapping: # Refdes map U?: U5 # Pad map P1: U5-P1 P2: U5-P2 P3: U5-P3 P4: U5-P4 # Layer map silk: silk component: layer1 data: # Actual data, or import directive, or whatever In actuality, if we had element groups, and allowed pins to be addressed through their group (U5-P1, U5-P2, etc), there would be no need to map the pads explicitly. I think that "pad" should be a primitive type, which is just a textual identifier. It could then be attached to geometric shapes, be a member of a group, and be referenced in netlists. Andrew _______________________________________________ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user