User Guide

InfoFile
The apertures which have not been found are then listed in the file
name.gpi, where name here stands for the name chosen for the output
file.
You can then change your board in such a way that the existing aper
-
tures can be used. After generating plot or drill files you should always
checktherelatedinfofiles.
ApertureEmulation
If objects exist in a drawing which are not compatible with the available
aperture sizes, it is possible to emulate the desired dimensions by select
-
ing the Emulate Apertures option. The CAM Processor then selects
smaller apertures to emulate dimensions which are not matched by aper
-
ture sizes. Emulation results in longer plot times and higher costs, so it
shouldbeavoidedwheneverpossible.
Thermal or annulus apertures are only emulated with draw apertures if
the Emulate Thermal or Emulate Annulus options, respectively, are acti
-
vated.
The file name.gpi indicates the need for emulation and which apertures
mustbeemulated.
Arcs with flat caps (CHANGE CAP FLAT) will always
be emulated
and drawn with short small wires (draw aperture). Arcs with round caps
won'tbeemulated.
Aperture Tolerances
If you enter tolerances for draw and/or flash apertures, then if the aper
-
ture with the exact value is not available the CAM Processor will use ap
-
ertures within the tolerances. Please bear in mind that your Design
Rulesmightnotbeobservedasaresultofallowingtolerances!
Refertofile name.gpi fortolerancesused.
DefiningtheApertureConfiguration
The CAM Processor distinguishes DRAW apertures from FLASH aper
-
tures. The first type is used to draw objects (e.g. tracks). The second
type is used to generate symbols (e.g. pads) by a light flash. Only if
draw apertures are defined can the plotter draw lines. Therefore, if the
plotter doesn’t distinguish between draw and flash apertures, you must
additionallydefineroundoroctagonalaperturesasdrawapertures.
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EAGLEManual