The MN-3257 is an I/O expansion device for Motionnet systems and is equipped with 32 isolated digital output channels. Each Motionnet communication line can be connected to up to 64 modules, meaning that the I/O can be expanded to 2048 output channels. The communication time required by each MN-3257 is 15.1 us. If 64 modules have been connected, signals for 2048 points on 64 modules can be sent and received within 0.97 msec. The update of the I/O status is completed automatically through the Motionnet system at a constant interval, and setting interrupts for specific input points that the customer wants to monitor can help prevent CPU time from being wasted by repetitive polling when there is nothing else for the issuing process to do. The internal flywheel diodes of each output port can be individually connected to different sources of power (each port is comprised of 8 I/O signals).