It's been a long time, The first thing is to see what version of the 
firmware is currently installed.  Then you follow the instructions which 
include taking off the top cover, finding a little slide switch, moving it, 
hooking the ts480 up to a computer with the cereal port and a cord, and 
running the software update program.
I can't remember more than that, its been maybe four years, and I have no 
idea what I did yesterday.  Oldtimers desease I guess.
I can look for more info, but maybe somebody else can add to my information.