The latest iOS update for POS says this in the What’s New: “Hardware barcode scanner can now be used to add discount codes”. There is no other information on this new feature so I emailed Shopify support. Here is what they said:
"So since this is a new feature there are some limitation right now while our developers work out some things and to improve it. Currently the discount codes only work if they are numeric only E.g "12345678" and the code has to already exist in the Shopify Admin.
To use this feature you can click on the discount code section and scan the # with the barcode scanner and hit apply. This feature works with both the 1D and 2D barcode scanners."
So I created a percentage off discount code called 12345678 and then used this web site to generate the barcode: https://www.free-barcode-generator.net/code-128/
I printed the barcode to a piece of paper and then was able to scan it when the discount screen was pulled up and Code was selected. The discount screen then auto closed and the discount was applied to the cart. That's pretty slick and will allow us to print out one page of discount codes for our clerks to scan. Although this will require keeping track of what actual promotion corresponds to each discount number so the reports make sense.
The number IS the discount code that you enter. For example 11111113 is a valid barcode 128 format. You use the barcode by scanning it when you first get into the discount screen on the cart. The POS will recognize that the barcode you created and scanned correlates to that number. You just have to know what that discount is to you to make sense of it later.