Appendix A. Performance Data278 PACSystems* RX7i, RX3i and RSTi-EP CPU Reference Manual GFK-2222ADA-3.2 What the Sweep Impact Tables ContainIn some tables, functions are shown as asynchronously impacting the sweep. This means that there isnot a set phase of the sweep in which the function takes place. For instance, the scanning of all I/Omodules takes place during either the input or output scan phase of the CPU’s sweep. However, I/Ointerrupts are totally asynchronous to the sweep and will interrupt any function currently in progress.The communication functions (except for the high priority programmer requests) are all processed withinone of the two windows in the sweep (the Controller Communications Window and the BackplaneCommunications Window). Sweep impact times for the various service requests are all minimum sweepimpact times for the defined functions, where the window times have been adjusted so that no timeslicing (limiting) of the window occurs in each sweep. This means that, as much as possible, each functionis completed in one occurrence of the window (between consecutive logic scans). The sweep impact ofthese functions can be spread out over multiple sweeps (limited) by adjusting the window times to avalue lower than the documented sweep impact time. For the programmer, the default time is 10 ms;therefore, some of the functions listed in that section will naturally time slice over successive sweeps.
