 C166 User's Guide | |
| Home Products Events Support | |
Technical Support
On-Line Manuals
C166 User's Guide
C166 Introduction Compiling Programs Language Extensions
Keywords Memory Models Tiny Model Small Model Medium Model Compact Model Large Model HCompact Model HLarge Model XLarge Model Memory Types near far bdata ebdata idata sdata huge xhuge Memory Type Comparison Pointers with Memory Types Implicit Memory Types Type Qualifiers const volatile Data Types Special Function Registers sfr Types sbit Types bit Types Bit-Addressable Objects Function Declarations Return Values Register Bank Register Mask Interrupt Functions Fast Interrupts Cached Vectors Fast Register Banks Inline Functions Real-Time Function Tasks Inline Assembly Traditional Inline Assembly Extended Inline Assembly Register Use Use in Macro Definitions Preprocessor Advanced Programming Error Messages Library Reference Appendixsfr Types
SFRs are declared in the same fashion as other C variables. The only difference is that the data type specified is sfr rather than char or int. For example:
sfr P0 = 0xFF00; /* Port-0, address FF00h */ sfr P1 = 0xFF04; /* Port-1, address FF04h */
Names for sfr types are defined using the same method as other C variables. In the above example, P0 and P1 are the SFR name declarations. Any symbolic name may be used in an sfr declaration.
The address specification after the equal sign ('=') must be a numeric constant. Expressions with operators are not allowed. This constant must lie in the SFR address range 0xFE00-0xFFDE or in the extended SFR address range 0xF000-0xF1DE (for C167 family devices).
| Contact Site Map Press Privacy | Copyright © 2008 Keil™, An ARM® Company. All rights reserved. |
