the 8:10 card, a few changes in kicad-libs, fped, and more

Werner Almesberger werner at
Tue Jan 18 14:49:53 EST 2011

Yesterday, I made a few changes in kicad-libs to help with cleaning
up ben-wpan. These changes also affect others of my projects. I
don't think anyone else is using the items in question right now,
but that may change in the future.

kicad-libs: uSD ("microSD") is now "8:10 card"

The SD Card Association has trademarked various names surrounding
SD card technology, including microSD [1]. In order to be allowed to
use this restricted name, logo, etc., to identify a product, one would
have to obtain a license. This would apply to anyone making such a
product - which is quite contrary to the spirit of Copyleft Hardware.

Wolfgang has voiced concerns [2] that indiscriminate use of those
trademarks in qi-hardware products could eventually backfire. We
discussed this extensively on #qi-hardware (IRC) [3], and the best
name for identifying a device using this sort of interface we came up
with was "8:10 card". (The name also can't be too close to the
trademarked one, so cute ideas like "micro5D" or such won't work.) The
8 stands for the number of electrical contacts, and the 10 stands for
the approximate width of the mating area in millimeters, which is in
this case 9.6 mm.

This is for use without further context. If the type of card or
interface is already constrained by context, one can use a simpler
designator. E.g., Milkymist One refers to the 8:10 card simply as
"memory card."

My projects ben-blinkenlights, f32xbase, and ben-wpan contain boards
in the shape of an 8:10 card connector. These elements are provided by
the project kicad-libs. I've now renamed the corresponding schematic
symbol [4] and footprint [5], and updated the projects accordingly.

[1] Attribution Guidelines_011907.pdf
    (search for "over microSD")
    (search for "just a reminder")

ben-wpan: the "atusd" board is now called "atben"

For the same reason, I renamed the "atusd" board of ben-wpan to
"atben". "atusb" is still "atusb".

kicad-libs: pad type "bare" for PCB connectors

In kicad-libs, there are a few footprints for connectors formed by PCB
patterns, i.e., the 8:10 card and various pads [6] for pogo pins [7]
or other forms of ad hoc connectivity [8].

These pads were of type "normal", i.e., they were present in the
copper, solder mask, and solder paste layers. The solder paste
shouldn't be there, so I've now changed these pads to type "bare",
which removes the solder paste.

I've updated these footprints in ben-wpan/atben, ben-wpan/atusb,
ben-wpan/cntr, f32xbase/c2ben, and ben-blinkenlights.


fped and ben-wpan: new pad type "trace" for inside affairs

Sometimes, a footprint may contain something that isn't supposed to
connect to anything outside the board, e.g.,. a connection between
pads or a printed antenna.

Such a structure is only present on the copper layer but has neither
solder paste nor an opening in the solder mask. I've added a new pad
type for this to fped (SVN revision 5998), called "trace", changed the
antenna to it [9], and updated atben and atusb.


I think that's all for now :-)

- Werner

More information about the discussion mailing list