Opcode $01, huh? That was an SM510 opcode, but I don't see it in any SM511 manuals. I'm trying to find some SM511 source code to see if we can get any hints.

I played around with taking pics of the LCDs. I don't have any lighting equipment, so I'm getting shadows of the segments because I have to angle the lens slightly to avoid the glare of the flash.

http://www.seanriddle.com/tglcd3.jpg
http://www.seanriddle.com/tmntlcd3.jpg