A rotating buffer system for on-line collection of eye monitor data

Eye movement research often requires the rapid collection and handling of large amounts of data. Such collection would be impossible without the laboratory computer. This paper describes an eye movement data collection system developed for the DEC PDP-11/03 computer. The two central features of the system are a rotating buffer, which saves eye movement data in memory, and direct memory access routines for writing the data to disk. The paper also describes a procedure for testing this or any data collection system, provided the data sampling rate is known. The system presented here is sufficiently general that with slight modifications, it could be used for collecting a wide range of physiological responses, including evoked potentials.