The routing of the double layer board is on the top/bottom routing layers, also known as red and blue layers
The shortcut key used for wiring is PT, not PL.
8.1 Switching wiring layers
Vias can be used if switching directly from the red/blue layer. When wiring, press "*" in the keypad area to switch layers, or use ctrl+shift+wheel to switch layers. Both of these two methods can switch layers while wiring, which is more efficient.
Vias can also be placed individually, and the shortcut key is PV instead of PP (pads on multiple layers).
Vias are conductive holes, while pads are used for device soldering. The two are similar in shape but have different properties.
Double click to view properties
The red layer and the blue layer are different floors, just like the difference between the first floor and the second floor, so the line on the blue layer cannot be connected to the pad of the red layer. In this case, the pad 2 of R7 is not connected to the wire.
The pads of the in-line device can be linked regardless of the red layer or the blue layer, for example
8.2 Wiring Specifications
Wiring generally prohibits right and acute angles.
Under normal circumstances, the red layer and the blue layer are not parallel. For example, if the red layer is horizontal, the blue layer should be as vertical as possible.
If the wiring is not a special requirement, the length of the wire should be shortened as much as possible.
The power cord should be wider
Other specifications will be discussed later