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Command-Line Tools

RTX51 Tiny is fully integrated into the C51 programming language. This makes generating RTX51 Tiny applications very easy to master. To create an RTX51 Tiny program, you need only write C functions. No assembly programming is required.

To compile your RTX51 Tiny programs from the command line...

Invoke the compiler as normal. No special directives are required. For example:


The resulting RTXPROG.OBJ file contains the C code and RTX51 Tiny tasks you defined.

To link your RTX51 Tiny programs from the command line...

  • Specify the RTX51TINY directive on the linker command line.
  • Include the RTX_CONF.OBJ file in the list of object files (if you made configuration changes).

For example:


The RTX51TINY directive instructs the linker to link RTXPROG.OBJ with RTX_CONF.OBJ and to include the RTX51 Tiny library. An RTX51 Tiny program using the tasks created in your C files is created.


  • Do not create a main C function for your RTX51 Tiny programs. Create only task functions. The main C function is included in the RTX51 Tiny Library to start the operating system and task 0. If you include a main function in your application, you will receive a linker error indicating there are multiple public definitions of main.
  • You must create at least one task function in your program.
  • Your application must call at least one RTX51 Tiny function (like os_wait or os_create_task) for the linker to include the RTX51 Tiny Library.
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