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IAR Embedded Workbench for RX 5.20

__sfr

In this section:
Syntax

See Syntax for type attributes used on data objects.

Description

The __sfr memory attribute overrides the default storage of variables and constants given by the selected data model, and places individual variables and constants in data32 memory. Using this attribute also stops the compiler from using the instructions SMOVF and SSTR to access the data.

Use this memory type attribute for all special function registers (SFR) and pointers to SFRs, to avoid unexpected program behavior.

Storage
  • Address range: 0–0xFFFFFFFF (4 Gbytes)

  • Maximum object size: 2 Gbytes–1

  • Pointer size: 4 bytes.

Example
__sfr int x;
See also

Memory types.