Real-Time Workshop User's Guide

Basic Code Generation Options

To access the basic code generation options, select the Real-Time Workshop tab of the Simulation Parameters dialog box. Then select ERT code generation options from the Category menu.

Figure 9-1 displays the basic code generation options for the Real-Time Workshop Embedded Coder.

Figure 9-1: Basic Code Generation Options

Note    ert_main.c contains certain compile-time error checks on code generation options, intended for use during simulation only. You should remove these error checks, as instructed below, from your production version of ert_main.c

Setting the code generation options as follows will result in more highly optimized code:

• Deselect the MAT-file logging check box.

Also, remove or comment out the #if MAT_FILE... error check in your production version of ert_main.c.

Note that disabling logging causes the program to run indefinitely, regardless of the setting of the model's stop time.

• Deselect the Initialize internal data and Initialize external I/O data check boxes.

Initializing the internal and external data is a precaution and may not be necessary for your application. Many embedded application environments initialize all RAM to zero at startup. Therefore, reinitializing RAM to zero is redundant.

Note that nonzero initialization of your program's data structures is still performed when Initialize internal data and Initialize external I/O data are selected.

• Deselect the Terminate function required check box if you do not require a terminate function for your model.

Also, remove or comment out the following in your production version of ert_main.c:

• The #if TERMFCN... error check
• The call to MODEL_TERMINATE

• Select the Single output/update function check box. Combining the output and update functions is the default. This option generates the model_step call, which reduces overhead and allows the Real-Time Workshop to use more local variables in the step function of the model.

If you do not want to combine output and update functions, make the following changes in your production version of ert_main.c:

• Replace calls to MODEL_STEP with calls to model_output and model_update.
• Remove the #if ONESTEPFCN... error check.

• If your application uses only integer arithmetic, select the Integer code only option to ensure that generated code contains no floating-point data or operations. When this option is selected, an error is raised if any noninteger data or expressions are encountered during code generation. The error message reports the offending blocks and parameters.

Optimizing the Generated Code

Generating Code from Subsystems