ISO 11783 as a whole specifies a serial data network for control and communications on forestry or agricultural tractors and mounted, semi-mounted, towed or self-propelled implements. Its purpose is to standardize the method and format of transfer of data between sensor, actuators, control elements and information-storage and display units, whether mounted on, or part of, the tractor or implement. This part of ISO 11783 describes the Tractor ECU (TECU), the control function (CF) that provides the gateway between the network’s tractor and implement buses, as well as performing other functions. New requirements in this second edition are specified as version 2 TECUs and Working Sets. NOTE The Tractor ECU is also the control function (CF) that represents the tractor, or analogous functions within self-propelled machines, for functions such as the virtual terminal on the implement bus.