Recently, the robot technology is rapidly expanding, together with the performance improvement of PCs and microcomputers. Generally, a PC is suitable for the information processing of sensors in which the amount of the data to be processed is large, whereas a microcomputer is suitable for real time processing such as motor control etc. Therefore, a controller for a robot system with multi-DOFs consists of one PC and multiple microcomputers. In such a case, the information transfer between the PC and microcomputers becomes a key point to develop a useful distributed controller. Especially, this paper discusses the kind of command and the amount of data that are transferred by a CAN communication, and describes the verification result that the basic performances satisfy the specifications as the robot controller. Simultaneous executions of motor control and the data transferred by the CAN communication, which is applied between a PC and multiple microcomputers, are confirmed through experiments by using a real robotic system.