US Patent 7483630 Exchanging asynchronous system information using optical transmission

A method for sending and receiving asynchronous signals using optical techniques. The present invention implements open-drain circuit signaling utilizing a Finite State Machine and additional logic to reduce power requirements when transmitting asynchronous information via an optical transmission line. An embodiment exploits the 8 bit/10 bit encoder to detect errors and signal the beginning of valid data along the transmission line. The asynchronous signals may be transmitted during transitions in the Finite State Machine.