Monitoring system and interface apparatus therefor

Abstract

In monitoring systems for acquiring data about a subject, such as are used, for example, in the medical, scientific and engineering fields, determination of temporal relationships between data acquired from multiple monitoring devices is facilitated by means of an interface unit which interconnects the monitoring devices with tape recorders for storing the data and a computer for processing the data. The interface unit generates various timing and control signals including a time code signal. The interface unit supplies the time code signal to the recording devices for recording simultaneously with the data. The time code signal may be a linear time code (LTC) derived from a video sync signal generated by the interface unit for synchronizing a camera. A sampling clock signal for controlling digitizing of the analog data acquired by the system is derived from the time code signal. The time code signal may comprise a common temporal reference signal, for example the SMPTE used with NTSC format video or its European equivalent EBU used with the format. The video synchronization signal may itself be synchronized to and external timing signal, perhaps derived from one of the monitoring devices.