MESA 7i76U inputs changing state without changes to config

First off, my apologies for not responding earlier, I've been waiting for my 7i76u to be returned before moving forward plus chores around the homestead have been a hinderance for time.

As Peter said the board was tested and found within specs. Out of an abundance of caution, I ordered as 24 v laptop PS which I received it this morning. After putting it on my scope and monitoring it for several minutes I found only glitches of < .1 v while holding an output voltage of 24.5 v which was the same with the previous PS only at 24.1 v.

Next I reinstalled the MESA board and mapped the X,Y and Z limits to inputs 0,1,2 and the probe to input 4 with EStop on 5. Restarting LCNC with sserial set to 20xxxxxx I monitored the fldvoltage and the four analog inputs. 0,1,2 (the limit switches) reflected the fldvoltage at all times. The probe voltage (input 04) fluctuated wildly between 0-3 v until I grounded the probe plate at which time it matched the other three inputs.

Next step was to reset sserial back to 00xxxxxx and restart LCNC. None of
first four inputs responded as expected.

After shutting down and powering off the machine I remapped X/Y/Z limits, Probe and EStop inputs to inputs 04-08 respectively. After power up and restarting LCNC the Limits and EStop responded as expected, however the Probe on input 07 did not. LCNC sees it as triggered on startup and going low upon contact. OK, shutting down LCNC and changing the HAL file to invert input 07 then restarting pin 07 still responds the same, i.e. high on startup and going low when contact is made.

My next step will be to rewire all of the inputs as sourcing inputs by moving the power legs from the +24v buss to the GND buss, change HAL to reflect the changes and retest.

Taking a break for a couple of hours then I'll let you know of my progress.

Well, that didn't work. Inputs are back to sinking inputs as specified in the manual. I did comment out the PROBE input so it is not currently part of the configuration. However, on startup LCNC continues to show the EStop button activated so I cannot continue testing Homing.

Unable to continue at testing at this point.

These are the states of the inputs at this time:

 

And this is my HAL config:

 

Any help would be greatly appreciated.

7I76U inputs are always sinking so normal connection would be:

+24V --> SWITCH --> 7I76U input

If you look in halshow, hm2_5i25.0.7i76.0.0.input-07 will always be
in the opposite state as hm2_5i25.0.7i76.0.0.input-07-not, so choosing
one or the other should make a difference.

Thank you to everyone. I've finally got the EStop to work correctly, though I don't understand why. Apparently, it works opposite of the limit switches in that there must be a high signal on the pin at startup and EStop is triggered when the switch is opened. Regardless, I can now home and run as expected.

Normally you would use a NC switch for Estop and the you would use the true (no -not)
input to sense it. This is so that when Estop is not activated (switch = closed circuit),
iocontrol.0.emc-enable-in will be true so no Estop. Then when Estop button is activated
(switch= open circuit), iocontrol.0.emc-enable-in goes false, signaling an estop event.

Did you verify that estop-ext changes state when you change the Estop button from on to off?

Yes, I now have the estop working as you specified and have verified that it stops the machine when the button is mashed (OPEN).

I'm on to getting my HY_VFD spindle hooked up.

Thanks to all who have helped on this issues.