I called the 800 number in the manual, and spoke with Derek, who abruptly told me that the only place to look for codes was remote central.com, and that Panasonic did not release codes. He didn't know how the codes got out that are on RC for other models.
I was also told that there are no discrete codes for the 50LC13 after asking with whom elseI could talk about releasing the codes and why they did not use direct access buttons for input changes. Needless to say, I did not get a name, and was told that direct access cost too much. What horse sh1t. Although I am otherwise happy with the set, I may return it over this issue.
Jeff