There are two different ways of adding global fiducials to your PCB.
Global fiducials are used globally by all parts of the PCB and not by any specific part. Specific parts use what are called local fiducials. This naming convention is from the IPC specification.
1.The first way is to use the automatic features that are built into the PCB border properties panel. This is the easiest way to add fiducials.
2.The second way is to manually place the fiducial is by first clicking on the fiducial button in the add ribbon menu then moving the mouse cursor to the location that you want the fiducial to be and then clicking the mouse button.
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