A lo= t of this doesn't make sense. I'm hearing 2 things.

1) If the 0,0 origin coordinates are an absolute position from t= he PCB origin

then wouldn't the component origin be in t= he upper left corner of the PCB? But that

doesn't happen when = you import schematics to the PCB.=C2=A0 The diamond shape origin is
in = the center of this 805 component - no matter where this component is random= ly placed

onto the PCB grid.=C2=A0 The component origin cannot be= linked to absolute PCB coordinates.

2) I thought I hear= d that the origin written to the footprint file, happens to be the absolute= position
of the cursor when captured into the buffer.=C2=A0 How and wh= y would anyone create parts at 0,0 in the extreme
upper left corner of = a PCB?=C2=A0 I am guessing that the origin coordinates written to the footp= rint file, are related to
relative coordinates based on a local origin = and the cursor position.=C2=A0 If you Ctrl-M and create a local origin, the= n
position the cursor over the cross hairs - then the origin will be ca= ptured and written to the buffer as 0,0.=C2=A0 That
is my guess (if I c= an find some time - I'll test this theory).=C2=A0 If you don't have= these things co-incident - then you
will have a non-zero value for the= origin - and these numbers represent an offset.=C2=A0

BUT - and th= is is the kicker -=C2=A0 it does not seem to matter if you have an non-zero= offset in your footprint file.

I found this 0805.fp file= in my /usr/local/share/pcb/pcblib-newlib/geda

Element[0x00000= 000 "Standard SMT resistor, capacitor etc" "" "080= 5" 0 0 -3150 -3150 0 100 ""]

Which has the orig= in at 0.0.=C2=A0 I don't see any difference when I use this footprint i= n my layout or if I use this 805.fp footprint

I referred to = in an earlier post.

Element["" "Standard S= MT resistor, capacitor etc" "" "0805" 2850.00mil 2= 600.00mil -31.50mil -31.50mil 0 100 ""]

I can p= lace and work with either footprint. And when I search the packaged librari= es, I am finding some footprints with 0.0 origin

values and s= ome with non-zero/offset values.=C2=A0

Dave

On Mon= , Aug 17, 2015 at 9:57 AM, DJ Delorie <dj AT delorie DOT com> wrote:

> My understanding is the origin is located at
> (2850.00mil,2600.00mil).=C2=A0 And the reference designator is positio= ned
> at (-31.50mil,-31.50mil) relative to the origin.=C2=A0 How does one > interpret these (2850.00mil,2600.00mil) numbers for the origin?

The standard library should have (0,0) there, because that coordinat= e
in the Element[] field is its location relative to the PCB itself.
(If ome of them doesn't, it may affect where the element is placed
when you manually place it.)

I.e. that element is at (2850.00mil,2600.00mil) *on the pcb*.

Thus, pcb will position that element such that its mark falls on
(2850.00mil,2600.00mil).

--001a11c3781af6337b051d889e05--