A3 - M8 on
A4 - M7 on
M9 is both off.
So the A4 pin is now activated by the M7 command?
Thank you
I
It depends on a config.h setting when building grbl.
The source for 1.1f that I pulled of off Github has the M7 function active.
So, yes M7 activates pin A4
That is Fantastic! THANK YOU LarryM.