XRONOS is designed to read in time series from many (up to 50) consecutive input files (this is to avoid wasting disk space by chaining many input files in a single file). Time series from up to 3 different energy ranges can be handled simultaneously within XRONOS. Additional flexibility is provided by Input File Options, which are used, e.g. to perform algebraic operations on individual input files, shift times, apply barycentric time corrections etc.
In the question/answer user interface input data are specified by entering the input filenames, one by one, in response to the relevant questions. In the partial question/answer and command-driven user interfaces the input files are specified using the data command. Currently, two different kinds of input files are supported: Rate Buffers (with extension .rbf), which are binary files (4 different formats are available), and QDP files, which are ASCII files written according to the QDP/PLT standard. XRONOS input files can either contain binned data or unbinned data (i.e. input files containing the arrival times of individual photons).