ABSTRACT
This chapter describes the Sercos automation bus, an international standard (IEC61784/61158/61800) for communication between digital motion controls, drives, I/O, sensors, and ancillary devices. It includes definitions, a description of Sercos communication methodology, an introduction to Sercos hardware, a discussion of speed considerations, information on conformance testing, and information on available development tools. There have been three generations of the Sercos automation bus. The latest generation, industrial Ethernet-based Sercos III is described first, followed by Sercos I/II, the original fiber-optic-based versions of Sercos. There have been three Sercos generations. The first two generations utilized an application-specific integrated circuit (ASIC) as a hardware processing platform, fiber-optic transmitters/receivers, and a fiber-optic cable as the transmission medium. The third generation (Sercos III) operates at up to 100 Mbps utilizing a field-programmable gate array (FPGA), an ASIC, or a general-purpose communication controller (GPCC) and is based on standard Ethernet hardware.
