E-Stop latch question

I have an E-Stop latch configured in io.hal, it looks like the image below with the exception of the OR gate.It is working as it should.

I want to be able to reset to the OK state with an external push button (assume the external E-stop is not in the stop position)

My understanding is that all three inputs on the left need to be satisfied:
The ok-in pin seems to require a logic 1 (not just a positive edge)
The reset pin appears to just need a positive edge to latch the OK

Hence the addition of the proposed OR gate to poke the reset pin.

That still leaves the ok-in. From observation iocontrol.0.user-enable-out latches on and off when you click on the red X estop button in the axis GUI, so if I click on that once when I start Axis (to latch it high),  I can then reset any subsequent e-stops with my external button.

I suppose I could add yet another latch that gets set with my external button and then OR that latch output with iocontrol.0.user-enable-out and drive the ok-in pin with that 2nd OR gate.

I'm not sure if anything else causes iocontrol.0.user-enable-out to toggle low (other than clicking on the red X)? perhaps some other internal logic can toggle this low and I would be defeating that e-stop path if I latch the ok-in pin high.

Makes me wonder if someone else has come up with a more elegant solution to an external e-stop reset button?
 

 

I'm putting the final touches on an external push-button control board that has a big Estop button as well as buttons to do a host of other things, details here =>

forum.linuxcnc.org/21-axis/53701-please-...e-this-control-board

I mostly use my mill for "one of" prototyping so it's really common for me to interact mostly with the control board. So I prefer to use the control board buttons for as many commonly used things as possible. At the moment I can do most everything I want from the control board except reset the E-Stop. I would prefer to be able to do that without clicking in the GUI.