If data are written to disk or other device, the file format consists of a header containing parameters such as radio source, observing frequency, etc., and data transfer parameters such as S2 tape ID, transfer mode, start time and scan length, followed by the tape (reproduced acquisition system) data bits. A typical individual output file may be 960 MBytes in size, representing one minute of data at a rate of 16 MBytes/s. Various software on- and off-line utilities are provided within 2tci for diagnostics and to examine the contents of transferred data files. Data from disk may be written to output tape devices by using standard tape archive programs such as "tar". They can also be transferred to a more capable computer via fast links such as "fast ethernet" or FDDI if such support exists within the local computer. 2tci may be executed from the computer command line, within shell scripts, or within other programs for full flexibility to the user.
|Figure 4: S2-BPS - Processing Center S2-TCI Control System Overview. In the upper portion of the figure, 2tci accepts a user-input transfer configuration file, controls and monitors the S2 recorder and DMA Card (DMAC) systems, manages the DMA data bursts from S2 tape to final destination ("local" or "remote" processing RAM/disk), and writes a log file summarizing the data transfer results. The lower portion of the figure demonstrates the three data management/processing schemes described in Sect. 3. All aspects of S2-TCI operation may be performed as part of an automated unattended supervisory system (even under remote operation), as logically represented in the "Data (Burst) Management" functional block|
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