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IAR Embedded Workbench for RH850 3.20.x

Specifying a data model

In this section:

Three data models are implemented: Small, Medium, and Large. These models are controlled by the --data_model option. Each model has a default memory type and a default pointer size. If you do not specify a data model option, the compiler will use the Small data model.

Your project can only use one data model at a time, and the same model must be used by all user modules and all library modules. However, you can override the default memory type for individual data objects by explicitly specifying a memory attribute, see Using data memory attributes.

This table summarizes the data models:

Data model name

Default memory attribute

Placement of data

Small (default)

__brel

64 Kbytes RAM and 64 Kbytes ROM, anywhere in memory

Medium

__brel23

8 Mbytes in RAM and 8 Mbytes in ROM

Large

__huge

The entire 4 Gbytes of memory

Table 55. Data model characteristics


Caution

See the IDE Project Management and Building documentation for information about setting options in the IDE.

Danger

Use the ‑‑data_model option to specify the data model for your project; see ‑‑data_model.