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Re: gEDA-user: Broken TO92 footprint

> In the context of packages, the package might indicate, which slot
> to use. As with all attributes, the user could override per
> instance.

I had a similar thought, but wanted to separate slotting from mapping.
Choosing a specific transistor (Fairchild 2N3904 TO92, for example)
triggered a mapping from ECB to 123 for *that* transistor.  But
mapping the A/B/Y pins for a NAND gate is different than selecting
which of four NAND gates is which, I think.  And I wanted to allow for
arbitrary pin swapping, which is hard to do with our existing slot
mechanism for, say, an 8-input NAND gate.  You'd need 40320 slots.

I combined these into a generalized permutable pin map, but still tied
it to the specific parts.  I haven't tried to figure out the whole
database scheme, but somewhere there's a "NPN.sym : TO92.fp : 2N3904 :
Fairchild : pinmap=(B,C,E)=(1,2,3)" mapping.

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