A laboratory sample distribution system comprising sample container carriers, a central controller having a network interface, and transport modules is presented. Each transport module comprises a transport surface, wherein the transport surfaces form a transport plane, a controllable driver arranged below the transport surface and configured to move sample container carriers on the transport surface, and a control unit for controlling the driver. The control unit comprises a network interface. The central controller and the control units of the transport modules are connected by their corresponding network interfaces. Each control unit comprises first and second addressing terminals. The addressing terminals are connected sequentially in a daisy chain topology. The first addressing terminal is the first control unit in the sequence and is connected to a first reference potential and the second addressing terminal is the last control unit in the sequence and is connected to a second reference potential.