Logix5000 w/ ControlLogix - Event Task

First time using an Event Task in Logix.
And what I see makes no sense before I even start...

Created a new Task, and under "Configuration"
Type: Event
Trigger: Module Input Data State Change <-- When my input turns on, I need a reading from my Analog card
Tag: Local:2:I <-- What? So if my whole input card changes state? Why can't I select .Data.2?

Next thought, if I actually have 2 identically redundant photoeyes that should both trigger this event, can I do it from a single point? Or does that require 2 different Event tasks?
If I can't select "OR" for my Event Trigger, then should I do a periodic task that will poll @ 20ms intervals? (Input card RPI is 20ms) Then once it recognizes either of the inputs I'm watching, then "read the Analog card"

But creating a task that runs every 20ms could be a lot of scan time for that one particular program. I only need this sub-program to run 10% of the time. Can I disable a Periodic task when I don't want to run it?

The Event task is going to be triggered any time that the Input module in Slot 2 updates its input DWord value.

That will happen when the RPI times out, or when one or more inputs configured as a Change-Of-State input changes state.

You don't designate the inputs responsible for COS triggers using the Event Task definition, but rather in the Configuration dialog for the Discrete Input Module.

I'm not sure how you'd force a sample of the Analog Input module.

You're correct that you can disable and enable Tasks programmatically using an SSV instruction.

You configure which input bits will cause a "Change-of-State" notification in the configuration of the input module.

The event task is not triggered by looking at the input data tag, it is triggered by the module itself.

Your redundant inputs can both be set to "COS" and will both cause the Event Task to run. You may need to think about how to handle the event task being triggered twice for what is the same "event".

EDIT: I might retract this post - got to run some tests

I ran tests.... The event task is NOT executed when bits change state that are not configured as COS

Clarification of Ken's post....

The event task only gets triggered when the data changes on bits that are configured to cause a COS event (input module configuration). Strangly, by default, they are all enabled. Turn off the bits you don't want to trigger the event task, and also choose Off-to-On, or On-to-Off as appropriate to your needs.

EDIT: I might retract this post - got to run some tests

Testing complete - the event task is only executed for bits that are enabled as COS in the input module configuration

Ken Roach said:

I'm not sure how you'd force a sample of the Analog Input module.

Click to expand...

Oops, my comment was a bit ambiguous.
I meant I want these Discretes to power an Event Task, which I will then use Ladder to sample my Analog

daba said:

The event task only gets triggered when the data changes on bits that are configured to cause a COS event (input module configuration). Strangly, by default, they are all enabled. Turn off the bits you don't want to trigger the event task, and also choose Off-to-On, or On-to-Off as appropriate to your needs.

Click to expand...

Alright, I see how this is set up now.
I have to order a terminal strip now, I didn't expect to have to actually test IO, so I left all of them in my wired PLC and just took the cards to my shop :S