Display CompactLogix Array tag in a Perspective Table

Ignition
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I have an array tag in a MicroLogix called Drop_Table. It is 12 elements long. Each element has two values: Target and Actual. All Values are REAL type. I would like to display this in a Perspective Table. I am able to see the values in my Tag Browser but I cannot seem to get them to display in a Table. I'm using Ignition 8.1. Any help would be greatly appreciated.

Thanks in advance!

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Show us how you have set up the table component's data binding.

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This is a Binding on data under PROPS

I read that I may need create a Custom Property and \ or add a transform. I have not had any luck with that.

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You are delivering a single value to props.data. A table needs either a dataset, or a list of objects. A number, or a list of numbers, is neither acceptable format. You absolutely need a transform.

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Where can I find some info on that? I read that I needed to create a list of dictionaries. Not sure if this is correct. I tried this:

def transform(self, value, quality, timestamp):
	return [{"Target": row[0], "Actual": row[1]} for row in value]

I get Error_ScriptEval.

I've tried this with a simple array also with the same bad results.

Here's what my data looks like:

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The problem is you don't have an array tag at [edge]Drop_Table - it's just a folder. In that folder are more folders, and in those folders are tags.

It might be a UDT array in your PLC program but it's not an array of any kind once you bring it into Ignition via whatever driver.

err, and side note: you must have meant Micro800 driver, right? There are no tags or tag arrays in MicroLogix.

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You are correct. That should have been CompactLogix.

What's the best way to bring this in as an array?

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You cannot.[1] The driver doesn't expose arrays as arrays, but as individual items.

When subscribed via OPC tags to all of those items, the driver intelligently reads them as a block, but they are delivered individually.

In your UI, you will want to supply the table with a list of tag paths as one of the values in the list of dictionaries, and configure a cell render view to indirect bind to show the live value in the table.

If you don't care about live values, you can use a script to with system.tag.readBlocking() to grab all of the values at once, and deliver the values in the dictionaries.

  1. My alternate EtherNet/IP driver does support reading arrays of simple numeric types as a single array item. ↩︎

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I am interested in learning more about your alternate Ethernet\IP driver.

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