Specify a maximum word length, in bits, for which the code generation process generates system-defined multiword type definitions.
Category: Code Generation > Interface
Default:
256 for ERT targets, 2048 for
GRT targets
Specify a maximum word length, in bits, for which the code generation process
generates multiword type definitions into the file
multiword_types.h. All
multiword type definitions up to and including this number of bits are generated. If
you select 0, multiword type definitions are not generated into the file
multiword_types.h.
The maximum word length for multiword types only determines the type definitions
generated and does not impact the efficiency of the generated code. If the maximum
word length for multiword types is set to 0 or too small, an error occurs when the
generated code is compiled. This error is caused by the generated code using a type
that does not have the required type definition. To resolve the error, increase the
maximum word length and regenerate the code. If the maximum word length for
multiword types is larger than required, then multiword_types.h
might contain unused type definitions. Unused type definitions do not consume target
resources.
Adding a model to a model hierarchy or changing an existing model in the
hierarchy can result in updates to the shared
multiword_types.h file during code generation. These
updates occur when the new model uses multiword types of length greater than
those of the other models. You must then recompile and, depending on your
development process, reverify previously generated code. To prevent updates
to multiword_types.h, determine a maximum word length
sufficiently big to cover the needs of all
models in the hierarchy. Configure every model in the hierarchy to use that
same maximum word length.
The majority of embedded designs do not need multiword types. By setting maximum word length for multiword types to 0, you can prevent use of multiword variables on the target. If you use multiword variables with a maximum word length that is 0 or smaller than required, you are alerted with an error when the generated code is compiled.
This parameter requires an Embedded Coder® license when generating code.
This parameter is enabled by selecting the value User
defined for the parameter Multiword type
definitions.
| Parameter: MultiwordLength |
| Type: integer |
| Value: valid quantity of bits representing a word size |
Default:
256 for ERT targets, 2048 for GRT
targets |
| Application | Setting |
|---|---|
| Debugging | No impact |
| Traceability | No impact |
| Efficiency | No impact |
| Safety precaution | No recommendation |