INFORMATION PROCESSING APPARATUS AND METHOD, COMMUNICATION APPARATUS AND METHOD, AND INFORMATION PROCESSING SYSTEM

摘要

An information processing apparatus includes: a register holding a value input thereto; a first communication path through which an addition command is input; a second communication path through which a subtraction command is input; addition means adding a predetermined value to a register value held in the register according to the addition command input through the first communication path and causing the register to hold a value resulting from the addition; and subtraction means subtracting a predetermined value from a register value held in the register according to the subtraction command input through the second communication path and causing the register to hold a value resulting from the subtraction, wherein the addition means and the subtraction means operate exclusively of each other.