Toy construction system with robotics control unit

A toy construction robotics system including a robotics control unit, the robotics control unit comprising: a housing comprising coupling elements configured for releasably interconnecting the robotics control unit with cooperating toy construction elements; a processor comprising programmed instructions; a plurality of I/O-ports connected to communicate with the processor; a plurality of separate light emitters arranged in a two-dimensional array on a front side of the housing, each of the light emitters being operable in response to instructions from the processor so as to produce at least two different indicator states; wherein the light emitters are aligned with respect to the I/O-ports such that each of the I/O-ports has an associated light emitter next to it. The light emitters may be operable, in response to instructions from the processor, to produce a machine readable code encoding data in respect of the robotics control unit. The machine readable code may comprise instructions for interaction between the robotics control unit and an external device.