ASIC, FPGA or GPCC-based SERCOS interface controllers are normally integrated into master motion controls as well as drives, amplifiers and I/O modules. They simplify the task of the designer by automatically handling most SERCOS interface communication functions. A set of over 500 standard software functions (called IDNs) defines standard motion and I/O functions. In addition, the interface allows for manufacturer-specific IDNs, which can be used to define unique functions, not addressed by the standard IDN set. In a SERCOS interface system, all servo loops are normally closed in the drive. This reduces the computational load on the motion controller, allowing it to synchronize more motion axes than it otherwise could. In addition, closing all the servo loops in the drive reduces the effect of the transport delay between the motion control and drive.