A Spectrometer Control Subsystem with High Level Functionality for Use at the National Synchrotron Light Source

We have developed a subsystem capable of controlling stepping motors in a wide variety of VUV and x-ray spectrometers to be used at the National Synchrotron Light Source. The subsystem is capable of controlling up to 15 motors with encoder readback and ramped acceleration/deceleration. Both absolute and incremental encoders may be used in any mixture. Function commands to the subsystem are communicated via ASCII characters over an asynchronous serial link in a well-defined protocol in decipherable English. Thus the unit can be controlled via write statements in a high-level language. Details of hardware implementation will be presented.