1. A digital controller for controlling a plurality of objectives to be controlled, which objectives are of the same kind, wherein a plurality of processors are provided in correspondence to said plurality of objectives, comprising: an instruction memory for storing instruction codes which are provided as a common control program for controlling said plurality of processors to execute said objectives, and addresses of storage locations holding operand addresses associated with said instruction codes; common control means connected to said instruction memory and said plurality of processors for reading out an instruction code and the associated storage location address from said instruction memory to all of said processors, and for generating a parallel execution process signal in each of said processors to effect execution of said instruction code in parallel by said processors; an operand memory provided in each of said processors, each operand memory having storage locations storing operand addresses, which storage locations are accessed by the same storage location address read out from said instruction memory; and an input/output data buffer memory provided in each of said processors and operatively associated with the operand memory therein for storing data accessed by the operand addresses stored in said operand memory; wherein a similar operation is carried out in each of said processors in parallel in response to the same instruction code read out from said instruction memory and data accessed from the input/output data buffer memory provided in each of the processors on the basis of the operand address which is obtained by accessing the operand memory with the storage location address associated with the instruction code read out of said instruction memory.