Memory Tag to count from 1 to 1200 when the action button clicked

Ignition
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1

I want the memory tag to count from 1 to 1200 when the one button is clicked in View A. This memory tag will be binded to label component in View B.
I tried to execute this in memory tag, but not working,

counter = system.tag.readBlocking(["[~]counter_tag"])

	counter = counter + 1

	system.tag.writeBlocking(["[default]My/Tag/counter"],["counter"])

Counter
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2

Read blocking will return a list of tag objects, to get the value of the first (and only) tag you should

counter = system.tag.readBlocking(["[~]counter_tag"])[0].value

if counter >= 1200:
     counter = 1
else:
     counter += 1

system.tag.writeBlocking(["[default]My/Tag/counter"],[counter])

You also seem to be writing a string as the value, and not the variable counter

1 Like
3

Thank you for your reply. Need a clarity how it will update continuously when I click one button in View A.

4

A computer can count from 1 to 1200 EXTREMELY fast... It's likely you won't see anything but 1200.

Do you want to count 1200 seconds?

Do you want this to be on a per-client basis? i.e. each client can have a different timer?

If global, you want to set the datetime you press the button in a memory tag, then in an expression memory tag, use the expression:

if(isNull({date/tag}), -1, secondsBetween({date/tag}, now(1000))) // these might be the wrong way around, I always swap them...

To stop it, use an on value change event on the counter tag to set the date tag value to None if its value is > 1200. If you want it to reset after 1200 that is.

If you want it client based, I'd use sessions props to do the same thing

3 Likes
5

Thankyou for your reply. Will workout and update

6

This and your other timer questions should really be handled by the PLC. I think you are building a fragile system that will break.

7

I didn't see the other timer questions, but if this is for control, certainly what @Transistor says is a must. SCADA is not for process control logic