The WIRE command is used to add wires (tracks) to a drawing. The wire begins at the first point specified and runs to the second. Additional points draw additional wire segments. Two mouse clicks at the same position finish the wire and a new one can be started at the position of the next mouse click.
Depending on the currently active wire bend, one or two wire segments will be drawn between every two points. The wire bend defines the angle between the segments and can be changed with the right mouse button (holding the Shift key down while clicking the right mouse button reverses the direction in which the bend styles are gone through, and the Ctrl key makes it toggle between corresponding bend styles).
Pressing the center mouse button brings a popup menu from which you may select the layer into which the wire will be drawn.
The special keywords ROUND and FLAT, as well as the curve parameter, can be used to draw an arc (see below).
Signal name
The signal_name parameter is intended mainly to be used in
script files that read in generated data. If a signal_name
is given, all subsequent wires will be added to that signal and no
automatic checks will be performed.
This feature should be used with great care because it could result
in short circuits, if a wire is placed in a way that it would connect
different signals. Please run a
Design Rule Check after using the WIRE command
with the signal_name parameter!
Wire Width
Entering a number after activating the WIRE command changes the width of the wire (in the present unit) which can be up to 0.51602 inch (13.1 mm).
The wire width can be changed with the command
CHANGE WIDTH width *at any time.
Wire Style
Wires can have one of the following styles:
Note that the DRC and Autorouter will always treat wires as "Continuous", even if their style is different. Wire styles are mainly for electrical and mechanical drawings and should not be used on signal layers. It is an explicit DRC error to use a non-continuous wire as part of a signal that is connected to any pad.
Signals in Top, Bottom, and Route Layers
Wires (tracks) in the layers Top, Bottom, and ROUTE2...15 are treated as signals. If you draw a wire in either of these layers starting from an existing signal, then all of the segments of this wire belong to that signal (only if the center of the wire is placed exactly onto the center of the existing wire or pad). If you finish this drawing operation with a wire segment connected to a different signal, then EAGLE will ask you if you want to connect the two signals.
Note that EAGLE treats each wire segment as a single object (e.g. when deleting a wire).
When the WIRE command is active the center mouse button can be used to change the layer on which the wire is drawn.
Do not use the WIRE command for nets, buses, and airwires. See NET, BUS and SIGNAL.
Drawing Arcs
Wires and arcs are basically the same objects, so you can draw an arc either by using the ARC command, or by adding the necessary parameters to the WIRE command. To make a wire an arc it needs either the curve parameter, which defines the "curvature" of the arc, or the @radius parameter, which defines the radius of the arc (note the '@', which is necessary to be able to tell apart curve and radius).
The valid range for curve is -360..+360, and its value means what
part of a full circle the arc consists of. A value of 90, for instance,
would result in a 90° arc, while 180 would give you a semicircle.
The maximum value of 360 can only be reached theoretically, since this would
mean that the arc consists of a full circle, which, because the start and end points
have to lie on the circle, would have to have an infinitely large diameter. Positive
values for curve mean that the arc is drawn in a mathematically positive sense
(i.e. counterclockwise). If curve is 0, the arc is a straight line
("no curvature"), which is actually a wire. Note that in order to distinguish the
curve parameter from the width parameter, it always has to be given with
a sign ('+' or '-'), even if it is a positive value.
As an example, the command
WIRE (0 0) +180 (0 10);would draw a semicircle from the point (0 0) to (0 10), in counterclockwise direction.
If a radius is given, the arc will have that radius. Just like the curve parameter, radius also must have a sign in order to determine the arcs orientation. For example, the command
WIRE (0 0) @+100 (0 200);would draw a semicircle from the point (0 0) to (0 200) (with a radius of 100), in counterclockwise direction. Note that if the end point is more than twice the radius away from the start point, a straight line will be drawn.
The arc radius can also be defined by placing the wire end point with the Ctrl key pressed (typically at the center of the circle on which the arc shall lie). In that case the point is not taken as an actual end point, but is rather used to set the radius of an arc. You can then move the cursor around and place an arc with the given radius (the right mouse button together with Ctrl will toggle the arc's orientation). If you move the cursor more than twice the radius away from the start point, a straight line will be drawn.
In order to be able to draw any arc with the WIRE command (which is especially important for generated script files), the keywords ROUND and FLAT are also allowed in the WIRE command. Note, though, that these apply only to actual arcs (straight wires always have round endings). By default, arcs created with the WIRE command have round endings.
For performance reasons "round" endings are approximated by "half octagons" on some output devices.
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