There are several ways to accomplish toggling of bits in the PLC.

My personal favorite is to use an FB where the input comes from the HMI button input coming on.

The PLC is then responsible for changing the state of the associated bool tag.

I use an FB named "TOGGLE".  On leading edge change of the button input, it simply SETS the output to the opposite state of whatever the saved state is, and remembers the new state (it's why I use an FB).

There is a Toggle button option, but I found there were edge cases where it did things contrary to what was expected / required (before Unified HMIs of course).

Perhaps you are living the edge case?

Do you have a screenshot of the button event action(s)?

When pressed, (for testing) have the button TURN ON the bit.

If it turns on the bit, then all the HMI connection information with the bool tag with the PLCs equivalent bool tag is ok.  It helps identify where the problem exists.

AutoGen_1191645

This seems like the simplest thing in the world but for the life of me I cannot get the switch element in the MTP1500 Unified Comfort HMI to toggle the tag in the CPU1217C. The boolean tag exist in both the HMI and PLC.

I can read and write numerics as well as have the pilot indicators respond to boolean tags in the PLC.

I tried tagging the switch state and then including the single bit type with conditions. There is no event that corresponds to the switch state. I have a lot of these switches on the HMI and none of them work. I attached a screen shot and and hoping someone can tell what to do here.

 Hi, use the script.

use the switch event (InvertBitInTag).

good luck.