Tag Value Changed script not triggering in UDT

[pturmel]

Ok. Consider this topic's solution:

Resettable runtime counter

Hello, I'm trying to figure out how to create an expression for a runtime counter. I found this script that works: if({[~]P_1_RI.value}, if(IsGood({[~]P1_RT.value}),{[~]P1_RT.value},0)+1, if(IsGood({[~]P1_RT.value}),{[~]P1_RT.value},0)) However, I'm trying to figure out how I can add a 'reset' function that will allow the operator to reset the runtime counter to 0 if the button is pushed. Additionally, sometimes the operator will need to manually update the runtime counter and then the syst…

Note that using timestamps like this has a number of advantages over a counter tied to a timer:

• Only consumes Gateway CPU when a Perspective UI is actively watching, or the run/stop boolean changes. (A Vision UI can watch without any gateway load.)
• Preserves precision down to the update pace of the run/stop tag.
• Scales without risking tag event bottlenecks.

Edit: I knew I'd made a better example somewhere--took a moment to find it:

Curiosity? Gateway Timer Event Scripts

As Ryan suggests, don't count in a timer event. The timing is not very precise. To get retention of prior time, you need at least two timestamps to hold state, updated when the signal changes. A stop timestamp, and an adjusted start timestamp. The start timestamp needs to be adjusted backwards from now() by the amount accumulated before. Drop these tags into a test folder to see how to set this up: { "tags": [ { "valueSource": "expr", "expression": "if(\n\t{[.]RTO_Reset},…

In that example, the RTO_Accum expression tag is not required to be a tag. It can be moved to a UI expression (with suitable indirect tag bindings to retrieve the parts it needs).