How to specify finite simulation stop time in VI generated using SIT connection manager

Question

Hello,
I have a SIMULINK model which I want to run on a desktop ETS. I'm following this procedure:
1. Convert the SIMULINK model in a .DLL using RTW build in Matlab. The target of this build is nidll.tlc.
2. Create a host VI with required indicators and map the parameters using SIT connection manager.
3. Configure the DAQ (and then SIT connection manager generated the driver and IO files for me.)
4. Using LV project, run the driver on the desktop ETS and host VI on the host machine.
The code is working fine, without any error.
My question is this: Since in the driver VI, the simulation time is set to -1, which implies "continuous", the simulation goes on until I hit the stop button on the host VI.
I tried changing this default value to some other value. The simulation then does run for the defined amount of time but then I'm getting error 2206.
What is an appropriate way to stop the simulation on the RT target?
Thanks
Gayatri
PS: I'm using LV 8.5, LVRT 8.5, SIT 4.0, Matlab @2007a.

Answer 1

The VI in the Driver VI called SIT Initialize Model.vi has an input called time step (sec) (-1: use model time step) which does what you want it to. It doesn't actually affect the time step of the solver used in the built model DLL, just the rate at which the main base rate loop actually runs in real time. In fact, base rate loop period would be a better name for this control. If you set it, you won't alter your model, but you will be able to adjust the rate of the base rate loop.
Simply create a control from this input terminal on your driver VI and fill in an appropriate period in seconds. Make sure to set this value as default in the control so that the Driver VI remembers it.
You will have to take into account that your model will still think it's running at the time step it was compiled at. So your model simulation time and the actual wall clock time won't match up.
Jarrod S.
National Instruments