DJ Delorie wrote: > Not directly. I've built parts with "slots" for various input pin > permutations.
I just realized a few days ago how that trick could be used for pin swapping something like a two-input NAND. And then just last night I was doing pin swapping to get better routability.... on a 32kx8 SRAM. Let's see... 8 data lines, 15 address lines... 2^23 slots.... ummmm... The phrase "doesn't scale" comes to mind. There is a level of abstraction missing. Something like a "permutable" attribute. So a 74as30 might have: permute=a:1,b:2,c:3,d:4,e:5,f:6,g:11,h:12 as a default, mapping pin names to pin numbers. The "net list tool" could munge the attribute to a new mapping and then back-annotation is simply replacing the attribute with the new mapping. gschem needs some smarts similar to slotting to put the right pins on the schematics. -dave _______________________________________________ geda-user mailing list [email protected] http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
