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Customization Files

The C251 Compiler provides a number of source files you may modify to adapt your target program to a specific hardware platform. These files contain:

  • Code that executes upon startup (START251.A51)
  • Code that initializes static variables (INITEDAT.A51 and INITHDAT.A51)
  • Code that performs low-level stream I/O (GETKEY.C and PUTCHAR.C
  • Source code for memory allocation (CALLOC.C, FREE.C,INIT_MEM.C, MALLOC.C, and REALLOC.C).

The code in these files is already compiled or assembled and included in the C library. When you link your program, the code from the library is automatically included.

You may customize these files to adjust them to your requirements. If you are working with µVision IDE, we recommend that you copy the customization file in your project folder to make modifications. The modified version of the file may be added the same way as other source files to your project.

When you are working with command-line tools, you must include the object files of the modified customization files in the linker command line. The following example shows you how to include custom replacement files for START251.A51 and PUTCHAR.C:

L251 MYMODUL1.OBJ, MYMODUL2.OBJ, START251.OBJ, PUTCHAR.OBJ
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