A method and system are disclosed for transmitting data among robots and a controller computer system within an automated robotic library. A robotic library communication protocol is described for communicating among the robotic mechanisms and the controller computer system. The robotic library communication protocol defines multiple fields for each packet including a preamble field that describes a predetermined preamble value that is equal to a particular value. Data is transmitted among the robotic mechanisms and the controller computer system utilizing the robotic library communication protocol. Each packet that conforms to the protocol includes only the preamble value in the preamble field. Power is provided to the robotic mechanisms utilizing a power signal. Data that has been encoded according to the protocol is transmitted to the robotic mechanisms using the power signal.