User`s guide

6 Program Architecture
6-8
The pseudocode below shows the execution of a model in a real-time
singletasking system where the model is run at interrupt level.
rtOneStep()
{
Check for interrupt overflow
Enable "rtOneStep" interrupt
ModelOutputs -- Major time step.
LogTXY -- Log time, states and root outports.
ModelUpdate -- Major time step.
Integrate -- Integration in minor time step for models
-- with continuous states.
ModelDerivatives
Do 0 or more
ModelOutputs
ModelDerivatives
EndDo (Number of iterations depends upon the solver.)
Integrate derivatives to update continuous states.
EndIntegrate
}
main()
{
Initialization (including installation of rtOneStep as an
interrupt service routine, ISR, for a real-time clock).
While(time < final time)
Background task.
EndWhile
Mask interrupts (Disable rtOneStep from executing.)
Complete any background tasks.
Shutdown
}
Real-time singletasking execution is very similar to the nonreal-time single
tasking execution, except that the execution of the model code is done at
interrupt level.
At the interval specified by the program’s base sample rate, the interrupt
service routine (ISR) preempts the background task to execute the model code.
The base sample rate is the fastest rate in the model. If the model has