l2b - LORAL archive to binary file

Documentation for the MAXIMA archive extraction program:

Usage: l2b infile [outfile]
Files: binout.par (or other file specifying output parameters).
Input information: parameter file name, start time, stop time.

l2b extracts data from the input file and writes it to the output file. If the output file is not specified, the name is taken to be the input file name up to the first period/dot, with the extension ".dat". It begins by reading the input file header to find the descriptions of the stored parameters. It then makes sure that there is a valid frame counter.

Next it asks for the name of the file describing the needed output parameters, and reads that file. The file specifies the size of output record (fixed) in bytes, the number of channels, and then lists the parameters associated with each channel, and what format it should be written in. The output records are composed of the listed channels, a status number (set to 0 for good data), and 0's to fill out the rest of the record. The current formats are,

s - this interprets the input data as an unsigned 2 byte integer in the range 0 to 65535. It shifts the center of the range to 0 by subtracting 32768, and outputs it as a signed 2 byte integer in the range -32768 to 32767. This is appropriate for data collected by the DAS A/D converter.
b - this interprets the input data as a signed 2 byte integer, and passes it throught unchanged, outputting it as a signed 2 byte integer. This is appropriate for digital words and the ACS data that comes through the SIM.

Finally, l2b asks for the start time and stop time for the extracted data segment. The default day is that of the start time of the file, and the user can give one of three formats:

days:hours:minutes:seconds
hours:minutes:seconds
digital hours

Days, hours, and minutes are integers. Digital hours and seconds are real numbers.

At this point l2b finds the beginning of the data segment, displays a note that it has found the beginning and extracts data. If there are discontinuties in the frame counter, diagnostic messages are printed. When the frame counter is bad, or if there are missing frames, the data is recorded as all 0's and the status number is set to 2.

Check the source code directory for documentation on the source code. This directory is currently: //garbo.berkeley.edu/lange/users/wilbanks/max/loral/source

author: Thor Wilbanks

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