Might be easier for you to just add another text box on the form. For instance, you could call it txtcounter. You can set its Visible property to No if the user doesn't need to know how many he's scanned.
In the After Update event of LID, Op, Time, Process, you have a line that says
It wouldn't hurt to do that in all of those fields, but probably Time and Process are the only two that are necessary. Depends on how you expect the screen to be used.
Then, in the code that kicks off when each one is scanned, you put code like this:
Code:
txtCounter = txtCounter + 1
That's it.