how to Auto Advance cells in Excel

I have a real simple spread sheet that I am using to keep track of serial numbers and Property ID Numbers on computers. The thing is I am using a Barcode Scanner hooked up to a laptop to enter the numbers. What I am looking for is a way to advance to the next cell in a row automaticly after X amount of characters have be entered into the previous cell. This way i would be able to just continue scanning bar codes without having to go back to the keyboard and hit the tab key or the downarrow thenhome key to start a new row. I tried messing around with macros but I do not know enough about them.
Thanks