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µVision3 User's Guide

µVision3 Overview User Interface Creating Applications Utilities Debugging Debug Commands Debug Functions Simulation Flash Programming Dialogs File Device Database License Management Single-User License Floating-User License Floating License Administrator Edit Find in Files Configuration Editor Colors & Fonts User Keywords Shortcut Keys Templates View Symbol Window Project Components, Enviornment, and Books Project Components Folders/Extensions Books Multi-Project Select Device Options Device Properties Target Target (Keil ARM) Target (Keil C51) Target (Keil C166) Target (Keil C251) Target (GNU ARM) Target (RealView ARM) Output Output (Keil) Output (GNU ARM) Output (RealView ARM) Listing Listing (Keil) Listing (GNU ARM) Listing (RealView ARM) User Keil EC++ Compiler Compiler Keil CA ARM Compiler Keil Cx51 Compiler Keil C166 Compiler Keil C251 Compiler GNU ARM C Compiler RealView ARM C Compiler Assembler Keil AA ARM Assembler Keil Ax51 Assembler Keil A166 Assembler Keil A251 Assembler GNU ARM Assembler RealView ARM Assembler Linker Keil LA Locate Keil LA Misc Keil BL51 Locate Keil BL51 Misc Keil Lx51 Locate Keil Lx51 Misc Keil L166 Locate Keil L166 Misc GNU ARM Linker RealView ARM Linker Debug Utilities Batch Build Debug Breakpoints Debug Settings Logic Analyzer Memory Map Performance Analyzer Function Editor Tools Setup PC-Lint Customize Tools Menu SVCS Configure Version Control Example Programs Command Line Appendix

RealView ARM C Compiler

Preprocessor Symbols

Sets preprocessor symbols which may be checked with #if, #ifdef and #ifndef. The defined names are copied exactly as they are entered (case-sensitive). Each name may get optionally a value. Define: Check, NoExtRam, X1=1+5 is identical to the following C preprocessor #define statements:
   #define Check
   #define NoExtRam
   #define X1 1+5
Clears previous Define assignments that are entered in the options dialog of a higher Target or Group level.

Language / Code Generation

Enable ARM/Thumb Interworking
Generates code that may be called in any CPU mode (ARM or Thumb).
Control compiler code optimization for the generated code:
  • Default: Use the compiler default or the setting of a higher Target or Group level.
  • Level 0 (-O0): Turn off all optimization, except some simple source transformations.
  • Level 1 (-O1): Turn off optimizations that seriously degrade the debug view.
  • Level 2 (-O2): High optimization (default level). The debug view might be less satisfactory because the mapping of object code to source code is not always clear.
  • Level 3 (-O3): Maximum optimization. Note that Level 3 in combination with Optimize for Time may generate more code that Level 2 since it may unroll loops.
Optimize for Time
Reduce execution time at the possible expense of a larger code size.
Split Load and Store Multiple
Instructs the compiler to split LDM and STM instructions into two or more LDM or STM instructions to reduce interrupt latency. When the LDM/STM have more than 5 (more than 4 when the PC is changed) CPU registers, several LDM/STM instructions are generated.
One ELF Section per Function
Generate one ELF section for each function in source file. Output sections are named with the same name as the function that generates the section. Allows to optimize code or to locate each function on individual memory addresses.
Strict ANSI C
Check for strict ANSI C conformance of the source file.
Enum Container always int
When disabled, the data type container for enum is optimize according the value range. When enabled, the data type container for enum is always signed int.
Plain Char is Signed
Instructs the Compiler to treat all variables declared with plain char as signed char variables.
Read-Only Position Independent
Generate position independent code for const (ROM) accesses.
Read-Write Position Independent
Generate position independent code for variable (RAM) accesses.
Control generation of warning messages.
Thumb Mode
Select explicit Thumb or ARM code for a file or file group. Note in the Target dialog Code Generation selects the default.
Include Paths
Allows you to supply one or more (separated by semi-colon) paths to search for header files. For #include "filename.h" the Compiler searches first the current folder and then folder of the source file. When this fails or when #include <filename.h> is used, the paths specified in the include paths box are searched. When this still fails, the paths specified in for the INC folder under Project — Components, Environment, Books ... are used.
Misc Controls
Specify any directive for which there is no individual dialog control.
Compiler Control String
Displays the current directives at the Compiler command line.
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