This is a project that represents a situation for which I was tasked. We have a test station that emits data on a Serial port. The data depends on the results of the tests being performed in a production environment. Successful components needed a label to be printed and affixed to them. This problem represents the usage of seveeral well known and well worn Arduino samples. One for a 16X2 LCD, another for an inexpensive keypad. The LCD displays short messages and an employee clock number, while the keypad is used to enter said clock number. Naturally for dealing with Serial to Arduino date, I used a MAX3232. THe program for the Arduino Mega deployed for this project is merely an Arduino IDE project. While there are plenty of demos for all of those little devices we can attach to an Arduino, it's a bit of a challenge picking from samples to comprise a working program. This is a simple project that shows how. Also, I have a good image of the hookups for the MAX3232. Basically the Arduino takes in serial data from the test station, looks for a few things after doing some rather tricky shaping of the data fields coming in, and then responds depending on that data and the success of that test, and prints a label Data comes into one Serial port of the Arduno Mega - chosen for its abundance of serial ports - and ZPL goes out another part of the Mega.