I have a Samsung 4940 that I use for Qult Show vending and there is only a few keys I need to have programmed. I need a one key with 7% tax and one for no tax. I need a key that I can put in different discounts for sale items.
I have a program manual but everything I try on it it gets an E1. I must be doing something wrong. How can I program this how I need it?