Re: gEDA-user: Mirrored headers: how do I define the footprints ?

[Karel Kulhavy <clock@xxxxxxxxxxxxx>]

On Mon, Dec 20, 2004 at 11:34:17AM -0700, Kim Lux wrote:
> I am laying out a board that connects to another board via 2 50 pin
> headers. (2 rows x 25 pins each on 0.100" spacings).  I've got a ccouple
> questions.... 
> 
> Question 1:
> 
> The first header is "normal", ie pin 1 is in the upper left corner of
> the header layout.  No problems there.
> 
> The second header is "mirrored", ie pin 1 is in the upper right corner
> of the header layout.  It is like this because the board developer
> originally intended for one board to be attached to each header and
> header 2 was supposed to be used on the underside of the board.  Thus,
> from the underside of the board pin 1 is in the traditional upper left
> location, but on the topside it is in the mirrored location. 
> 
> On the board that I purchased, both headers are soldered to the upper
> side. 
> 
> I am attaching my board from the upper side only, thus the second
> headers has an unconventional pinout.  How do I define a footprint with
> a "mirrored" pinout (without renumbering the pinout) ?  Or will
> renumbering the pinout be the easiest way ?

It's possible to mirror buffer I think

> 
> I'd like not to renumber the pinout for 2 reasons:
> 
> a) the schematic for the purchased board uses the underside pin
> numbers. 
> 
> b) someday I might build a board that uses only the second header and
> mounts underneath the purchased board.  
> 
> 
> 
> Question 2:
> 
> I am using the 50 pin connectors as templates for my new connectors.  (I
> am going to modify the pin names, etc. because I will be making a number
> of boards to attach to these headers.) 
> 
> Specifically, I am using header50-3.sym.  I've noticed that this and
> other 50 pin headers do not have a defined footprint in the symbol.  Why
> is this ?  Does the user define the footprint when it is used in the
> schematic to make it more versatile ?  Am I missing something ?    

It's probably that PCB isn't still intended as The Only Right Default
Choice (TM) for gschem as PCB and gschem are treated as separate products.

But I suggest that the default things would be set up for PCB and if someone
wants to use something commercial (or something documented in weird
regional languages ;-) ) then he'll just edit it.

Cl<