 Cx51 User's Guide | |
| Home Products Events Support | |
Technical Support
On-Line Manuals
Cx51 User's Guide
Cx51 Introduction Compiling Programs Language Extensions
Keywords Memory Areas Program Memory Internal Data Memory External Data Memory Far Memory SFR Memory Memory Models Small Model Compact Model Large Model Memory Types bdata code data far idata pdata xdata Data Types Special Function Registers sfr sfr16 sbit Bit-Addressable Objects bit Standard C Types void char int enum float double Type Modifiers signed unsigned short long Type Qualifiers const volatile Storage Classes auto register extern static Absolute Variable Location Pointers Generic Pointers Memory-Specific Pointers Pointer Conversions Abstract Pointers Function Declarations Parameters and the Stack Parameters and Registers Return Values Memory Models Register Banks Register Bank Access Interrupt Functions Reentrant Functions Alien (PL/M-51) Function Real-Time Function Tasks Preprocessor Advanced Programming 8051 Derivatives Error Messages Library Reference AppendixData Types
The Cx51 Compiler provides several basic data types you may use in your C programs. The compiler supports the standard C data types as well as several data types that are unique to the Cx51 platform.
| Data Types | Bits | Bytes | Value Range |
|---|---|---|---|
| bit | 1 | 0 to 1 | |
| signed char | 8 | 1 | -128 — +127 |
| unsigned char | 8 | 1 | 0 — 255 |
| enum | 8 / 16 | 1 or 2 | -128 — +127 or -32768 — +32767 |
| signed short int | 16 | 2 | -32768 — +32767 |
| unsigned short int | 16 | 2 | 0 — 65535 |
| signed int | 16 | 2 | -32768 — +32767 |
| unsigned int | 16 | 2 | 0 — 65535 |
| signed long int | 32 | 4 | -2147483648 — +2147483647 |
| unsigned long int | 32 | 4 | 0 — 4294967295 |
| float | 32 | 4 | ±1.175494E-38 — ±3.402823E+38 |
| double | 32 | 4 | ±1.175494E-38 — ±3.402823E+38 |
| sbit | 1 | 0 or 1 | |
| sfr | 8 | 1 | 0 — 255 |
| sfr16 | 16 | 2 | 0 — 65535 |
Note
- The bit, sbit, sfr, and sfr16 data types are not provided in ANSI C. They are unique to the Cx51 Compiler.
| Contact Site Map Press Privacy | Copyright © 2008 Keil™, An ARM® Company. All rights reserved. |
