So I have a Momentary PB whose Control Value is pointing to a tag within a UDT that is passed into the object containing the button as a custom property. If I press this button, I cannot receive the input on the PLC end of things. The button binding is set as bidirectional and the gateway is in read/write.
If I just point the button control value to a regular tag, I am able to get input on the PLC.
Don’t pass in the UDT–I don’t think you can make that bidirectional.
Pass in the tag path to the UDT and combine that with the inner path to the button to make an indirect tag binding. And make that bidirectional.
Okay, I can make this work. However, is there any reason why UDTs can’t be written to after being passed? Seems like it would be a simple thing and convenient.
I'd be wary of using momentary buttons, as any comms hiccup might leave this tag high. I've seen it before usually in oem plcs, and it's become inhibitive of other actions until the tag is reset. We never use these for standard push buttons, and where we need a jog button or the like which is push-and-hold to action, we use fast periodic handshaking between plc/scada to check for comms dropouts and turn it off in the plc if the handshaking fails (or ideally a physical push button)