THANKS so much David, that works. Later I found this and others in the SIG command reference guide but NOT in the Xy4 command reference guide. I'm assuming that info got moved to the Xy4 customization guide which I have misplaced.
You could just execute the FUNC SI command from the command line.
> On Apr 16, 2022, at 7:40 AM, Bill Troop <billtroop@xxxxxxxxx> wrote:
>
> Does anyone happen to know how to turn on/off insert/overstrike mode? On my Macbook I have accidentally turned on overstrike mode . . . . but I don't know by what accidental key combination. There doesn't seem to be an insert key.