ZBasic Language Reference
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ZBasic Microcontrollers
3.30 Task Management
The ZBasic System Library has several routines that are helpful for managing tasks including LockTask(),
UnlockTask(), StatusTask(), ResumeTask(), RunTask() and ExitTask(). The latter four routines permit
some advanced task management for special situations. One use of these routines is to implement a
timeout on a task that is awaiting the completion of an event, e.g. an external interrupt or an input
capture. Normally, when a task is set to wait for an event like these it will wait indefinitely.
3.30.1 Task Control Block
Each task has an associated Task Control Block (TCB) - a data area that occupies the first few bytes of
the task stack in VM mode (the last few bytes of the task stack in native mode). In most cases, a program
will not need to access the contents of a TCB. The information is included here for those rare
circumstances when is needed. Use of this information is recommended for advanced programmers only.
When a task is activated its task control block is initialized and then inserted into a circular linked list
immediately following the task control block of the then-current task. The table below gives some
information on the structure of the task control block. It is important to note that this information is
considered implementation detail subject to change as necessary.
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