INtime® 3.1 Software - tenAsys

4 About RT programming
This chapter describes mechanisms appropriate to RT programming:
Note
For information about developing an RT application using INtime software, see Chapter 10, INtime
application development.
Mechanism Description Page
Multi-threading Switches between threads of execution. 39
Preemptive, prioritybased
scheduling
Interrupt processing
Determinism
Determines which thread needs to run immediately and which can
wait.
Responds to external interrupts that occur during system
operation.
Enables threads to execute in a predictable fashion, regardless of
the arrival of both internal and external events.
Multi-programming Allows more than one application to run at a time. 44
Inter-thread
Enables asynchronous threads, which run in a random order, to 45
coordination and
communication
coordinate and communicate with one another.
Messages Enables threads to exchange data, messages, or object handles. 46
Synchronization Enables threads to signal the second thread when a task is 47
completed.
Mutual exclusion Prevents threads from accessing data currently in use until
released.
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Memory pools and
memory sharing
System calls
Real time shared
libraries
Allocates memory to RT applications on request and manages
multiple memory requests.
Programmatic interfaces you use to manipulate objects or control
the computer's actions.
Libraries you build that can be shared by one or more real-time
applications.
Exception handling Causes and proper handling of system exceptions. 51
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Multi-threading
Multithreading means the computer stops running one thread and starts running
another, as shown in the next figure. INtime software manages thread switching, saving
the old thread’s context on the old thread’s stack and loads the new thread’s context
before starting execution. An INtime software thread is a thread of execution, similar to
a Windows thread.
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