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ARM Library Optimized for Embedded Applications
Improved in MDK-ARM v4.1x

MicroLib is a highly-optimized library for ARM-based embedded applications written in C. When compared to the standard C library included with the ARM Compiler toolchain, MicroLib provides significant code size advantages required for many embedded systems.

MicroLib Library Size Comparison

The primary differences between MicroLib and the standard C library are:

  • MicroLib is designed for deeply embedded applications.
  • MicroLib is optimized to use less code and data memory than using the ARM standard library.
  • MicroLib has been designed to work without an operating system, however this does not prevent it being used together with any OS or RTOS such as Keil RTX.
  • MicroLib contains no file I/O or wide character support.
  • As MicroLib has been optimized to minimize code size, some functions will execute more slowly than the standard C library routines available in the ARM compilation tools.
  • Both MicroLib and the ARM Standard Library are included in the Keil MDK-ARM.
  • See Differences from the default C library for more detailed information
MicroLib Selection in µVision3

To use MicroLib in your embedded application, select the MicroLib check box in µVision and compile your application. µVision links your program with MicroLib and reduces your program size quickly and easily.

Notes Note

  • MicroLib is included in MDK-ARM v3.1 and higher.
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