Sim Viewing Devices in External Mode
A sim viewing device encapsulates processing and viewing of
signals received from the target system in external mode. During simulation
in external mode, the target system uploads the appropriate input
values to the sim viewing device in the Simulink model. The sim
viewing device then conditions the input signals as needed and renders
the signals on the screen. A sim viewing device runs only on the host,
generating no code in the target system and, therefore, allowing extra
processing of displayed signals without burdening the generated code.
You can use your S-function as a sim viewing device in external
mode if it satisfies the following conditions.
The S-function has no output ports.
The S-function contains no states.
The generated code does not require the conditioned
signals produced by the S-function.
To specify a C MEX S-function is a sim viewing device, set the SS_OPTION_SIM_VIEWING_DEVICE option
in the mdlInitializeSizes function. For example
ssSetOptions(S, SS_OPTION_SIM_VIEWING_DEVICE);
To specify a Level-2 M-file S-function is a sim viewing device,
call the run-time object's SetSimViewingDevice method
in the S-function's setup callback method.
External mode compatible S-functions are selected, and the trigger
is armed, by using the External Signal & Triggering dialog box. For more information see Communicating With Code Executing on a Target
System Using Simulink External Mode in the Real-Time Workshop documentation.
 | Function-Call Subsystems | | Frame-Based Signals |  |
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