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Real-Time Function Tasks

The Cx51 Compiler supports the RTX51 Full and RTX51 Tiny real-time multitasking operating systems with the _task_ and _priority_ keywords.

  • The _task_ keyword specifies a function is a real-time task.
  • The _priority_ keyword specifies the priority for the task.

For example:

void func (void) _task_ num _priority_ pri


num is a task ID number from 0-255 for RTX51 Full or 0-15 for RTX51 Tiny.
pri is the priority for the task. Refer to the RTX51 User's Guide or the RTX51 Tiny User's Guide for more information.


  • Task functions must be declared with a void return type and a void argument list.
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