While trying to move to a new EDA package, Altium Designer, I had a really hard time finding out how to put a overbar, or overline on top of a pin designator. This is usually used for active low signals. In Eagle PCB you just put an exclamation in front of the signal, or around the part to have the overline, like !RST or !TST!/GPO. For Altium Designer, each letter that needs an overline should be suffixed with a backslash, e.g. R\S\T\. You’ll never find it in the Designer notes unless you know to look for backslash. The words overbar or overline are nowhere to be found. I hope that this saves someone some time!
Altium Designer Overbar or Overline
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