Patent ID: 7395410

Claim:
A processor system including a main processor performing an operation according to an operation instruction and a coprocessor, the main processor comprising: a plurality of registers to store data used for the operation and data obtained as a result of the operation; and an instruction decode control unit sequentially decoding instructions, and sending control signals in accordance with each of the instructions, wherein when decoding a request instruction designating (i) a type of operation to be performed by a coprocessor, (ii) a first data that specifies one of the plurality of registers as a first storage area to store data to be used to perform the operation of a designated type, and (iii) a second data that specifies one of the plurality of registers as a second storage area to store data obtained as a result of the operation of the designated type performed by the coprocessor, the request instruction including (i) a field storing an instruction identification code to distingnish the request instruction from other types of instructions included in all instructions executable on the main processor, (ii) a field storing a coprocessor operation code specifing the type of the operation to be performed by the coprocessor, (iii) a field storing the first data, and (iv) a field storing the second data, the instruction decode control unit prestores thereon time information indicating a time period required to complete the operation of the designated type and sends control signals (i) to send the coprocessor operation code included in the request instruction to the coprocessor, (ii) to send to the coprocessor, source data which is the data stored in the register specified by the first data included in the request instruction, and (iii) to write into the register specified by the second data included in the request instruction, resulting data obtained as a result of the operation of the designated type which is sent from the coprocessor when a time period indicated by time information corresponding to the type specified by the coprocessor operation code in the request instruction has elapsed after sending the coprocessor operation code and source data in the request instruction to the coprocessor, the coprocessor (i) decodes the coprocessor operation code sent from the main processor, (ii) performs the operation of the designated type of which is specified by the coprocessor operation code, by using the source data sent from the main processor, and (iii) sends resulting data which is data obtained as a result of the same operation to the main processor.