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101 lines
4.0 KiB
Plaintext
101 lines
4.0 KiB
Plaintext
/**
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@page LEVEL2 Real-Time Synchronization Design
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A simulation is "real-time" when it can consistently and repetitively execute
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its scheduled math models to completion within some predetermined interval
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time frame for an indefinite period of time. This predetermined interval
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time frame is referred to as the real-time frame. In this design the real-time
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frame is set equal to the simulation software frame. Real-time is achieved
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by periodically pausing simulation execution at the end of each real-time
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frame. If simulation execution has not finished by the end of each real-time
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frame then this is an overrun. The real-time synchronization capability has
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several user settable options when a simulation overruns. If simulation
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execution finishes before the real-time frame expires, this is an underrun. If
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the simuation is underruning, the real-time synchronization capability allows
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the simulation to "sleep" while waiting for the real-time frame to expire.
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Real-time synchronization defaults off when initializing the simulation.
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To enable real-time synchronization users or models may call enable() at any
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time during the simulation. To exit real-time synchronization users or
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models may call disable() at any time during the simulation. The actual
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entering or exiting real-time happens at the end of the frame.
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Listed below are the various modes of operation in a simulation and the
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responsibilities of the real-time synchronization class in each.
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@section LEVEL3 Pre-Initialization
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During pre-initialization the user may specify the behavior of the real-time
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synchronization class during overruns and underruns.
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- Set real-time synchronization enabled or disabled.
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- Set real-time sleep timer enabled or disabled.
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- Set the maximum number of consecutive overruns allowed. (default 100,000,000)
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- Set the maximum time allowed for single overruns (default 1e37 seconds)
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- Set action taken when maximum overruns achieved to freeze/terminate or
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terminate immediately (default terminate immediately)
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@section LEVEL3 Initialization and Restart
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The real-time initialization and restart jobs are designed to be the last
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jobs run before exiting initialization or restart mode.
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Initialize the underlying hardware.
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@copydetails Trick::RealtimeSync::initialize(long long , long long )
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Trick::RealtimeSync::initialize(long long , long long )
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@section LEVEL3 Start Real-Time
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@copydetails Trick::RealtimeSync::initialize(long long , long long )
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Trick::RealtimeSync::initialize(long long , long long )
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@section LEVEL3 End of Frame
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At the end of the real-time frame (also the software frame) the
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real-time synchronization class will determine if the simulation is
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underruning or overrunning and take actions to keep simulation time
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and real-time in sync.
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@copydetails Trick::RealtimeSync::rt_monitor( long long )
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Trick::RealtimeSync::rt_monitor( long long )
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@section LEVEL3 Freeze Mode
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@section LEVEL4 Freeze Initialization
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During freeze initialization the real-time synchronization class resets the real-time
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frame to the freeze frame and restarts the real-time clock and timer.
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@copydetails Trick::RealtimeSync::freeze_init( long long )
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Trick::RealtimeSync::freeze_init( long long )
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@section LEVEL4 Freeze Loop
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During freeze loop processing the real-time synchronization pauses the freeze loop.
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The pause is released when real-time equals the freeze loop period. No checks are
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done for overrunning or underruning a freeze period.
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@copydetails Trick::RealtimeSync::freeze_pause( long long )
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Trick::RealtimeSync::freeze_pause( long long )
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@section LEVEL4 UnFreeze
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During unfreeze the real-time synchronization class resets the real-time
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frame to the software frame and restarts the real-time clock and timer.
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@copydetails Trick::RealtimeSync::unfreeze( long long , long long )
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Trick::RealtimeSync::unfreeze( long long , long long )
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@section LEVEL3 Shutdown Mode
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During shutdow, the real-time synchronization class stops the clock and sleep
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timer hardware.
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@copydetails Trick::RealtimeSync::shutdown()
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Trick::RealtimeSync::shutdown()
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*/
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