The filter wheel driver software provides an interface to the Programmable Logic Controller (PLC) which controls one or more filter wheels. The software comprises a back-end, which communicates directly with the PLC over a serial link, and the front-end with which the user interacts. There are in fact a number of front-end interfaces available to control and query the filter wheels.
The software is modular, and may be used on its own (to control filter wheels not part of a larger system), or as part of interconnected systems (e.g. the Sutherland High-speed Optical Camera Cameras (SHOC) instrument, which includes filter wheels, a global positioning system (GPS) receiver used for timing information, and a charge-coupled device (CCD) camera.)
A basic command line interface is provided to control the filter wheel, but most users will find it preferable to use the provided web interface. There is also a diagnostic interface, which may be used by technicians for the purposes of trouble-shooting.