Programming protocols for a Life Cycle 3500?

I have a Lifefitness Lifecycle 3500 exercycle. This bike was manufactured in
the early 1990's and has a serial port for a connection to a Nintendo Game
console. There were a few game cartridges that would allow you to use the bike
interactively with a game.

I have been able to connect the serial port up to a PC and see a string of
repeated text coming from the exercycle. It says something like "Lifefitness
inc. all rights reserved". I'm sure the bike is waiting for the proper
protocol for control and examination of what the console is displaying.

My question is "Does anyone know where this information can be found?" I have
contacted Lifefitness but they don't seem to have a clue.

Thanks for any help.

A great*exchange of information.