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<title>1.4 Tasks</title>

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<h2>
  <a name="1204833"> </a><font color="#003366"  face="Verdana, Arial, Helvetica, sans-serif">1.4 	 Tasks</font>
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<p>
  <a name="1204837"> </a><font size=2  face="Verdana, Arial, Helvetica, sans-serif">Tasks are the main elements of the OS20 multi-tasking facilities. A task describes the behavior of a discrete, separable component of an application, behaving like a separate program, except that it can communicate with other tasks. New tasks may be generated dynamically by any existing task.</font>
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  <a name="1204838"> </a><font size=2  face="Verdana, Arial, Helvetica, sans-serif">Each task has its own data area in memory, including its own stack and the current state of the task. These data areas can be allocated by OS20 from the system partition or specified by the user. The code, global static data area and heap area are all shared between tasks. Two tasks may use the same code with no penalty. Sharing static data between tasks must be done with care, and is not recommended as a means of communication between tasks without explicit synchronization.</font>
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  <a name="1204842"> </a><font size=2  face="Verdana, Arial, Helvetica, sans-serif">Applications can be broken into any number of tasks provided there is sufficient memory. The overhead for generating and scheduling tasks is small in terms of processor time and memory.</font>
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<p>
  <a name="1204846"> </a><font size=2  face="Verdana, Arial, Helvetica, sans-serif">Tasks are described in more detail in <a href="task.htm#1204411"><font  color="#0000ff" face="Verdana, Arial, Helvetica, sans-serif"><i>Chapter

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