I'm using Mach 3 with the 2010 screen set.  I'm on Win 10 and using the USB UC100.
I used it a lot in the past then got sidetracked and some cables were moved around, etc.  No real changes but now homing icon doesn't respond.

It can't be a hardware problem though because manually sending G28.1 works ok.

Ive attempted to look at the button macros but somewhat confused in that respect.

I haven't reinstalled anything yet because I don't want to have to reconfig my entire setup again and I'm not sure which files to back up first.
thanks for reading and hope you can help me.
thanks.