Distributed control system and semiconductor inspection apparatus including same

Abstract

A distributed control system includes a tree topology network or a daisy-chain network including a communication parent station, communication child stations, and a plurality of communication paths among the communication parent station and the communication child stations, in which the communication parent station and the communication child stations include a scheduling unit that controls a transfer cycle that is temporal intervals of data transfer. The scheduling unit sets the transfer cycle that is the fastest out of a plurality of the data as a reference cycle, counts the number of times each time the reference cycle elapses, and imparts a value of the number of times to the reference cycle as a cycle number. When the cycle number reaches an optional number, the number of times is returned to an initial value, which makes one cycle of transfer control, and the transfer control is repeatedly executed. For the timing of the reference cycle at which the data is transferred, the scheduling unit defines a cycle number to which the reference cycle corresponds, on the basis of first information corresponding to the data.