Intelligent robot control using multiprocessors, sensors, and actuators requires real-time flexible networks for communicating various types of real-time data, e.g., sensing data and interrupt signals. Furthermore, serial data transfer is required for implementing the network using a few wiring lines. To meet these requirements, we propose a CDMA serial communication interface utilizing novel two-step synchronization. The transmitter and receiver chip fabricated with 0.25μm digital CMOS technology achieved 2.7Gcps (chips per second) and 7-multiplex communication. The experimental interface board was developed for demonstrating flexible transfer of multiimage data by installing CDMA chips in addition to an FPGA.

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