AUXILIARY PROCESSOR CONTROL SYSTEM

PURPOSE:To send an instruction of data processing to an auxiliary processor and to improve data processing efficiency by storing extended instructions which utilize an undefined instruction code of a main processor in a program memory. CONSTITUTION:When an instruction read out of the program memory 8 is an extended instruction, an extended instruction decision circuit 7 sends out NOP to a main processor 1 through an instruction code conversion circuit 6 and this extended instruction is stored in a shift register 5. A request for start interruption is sent out to the auxiliary processor after the extended instruction is stored,and the auxiliary processor 2 reads out the contents of the register 5 and accesses the bus of the main processor 1 through a bus control circuit 4, thereby executing the extended instruction.