Tag = value else Tag = opc value

Ignition
1

What’s the expression for doing this:
If tag0 == 1:
tag1 = 1
else
tag1 = value of opc item path xxxx

I can’t figure out how to do the opc part only

2

You can’t directly access an OPC path in an expression. You would need an OPC tag.
Then, with tag1 as an expression tag:

if([default]path/to/tag0} = 1,
   1,
   {[default]path/to/opcTag}
  )
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