INtime® 3.1 Software - tenAsys

Chapter 2: Understanding INtime software architecture
In addition to the usual thread activities, an interrupt thread can also:
• Cancel the assignment of an interrupt handler to an interrupt level.
• Wait for an interrupt to occur.
• Enable and disable interrupts.
This shows how an interrupt thread enters an event loop where it waits to service an
interrupt:
Figure 2-5. Thread execution model
Interrupt
Upon creation, the interrupt thread uses an RT system call to set up an RT interrupt and associate
itself with this interrupt. Normally, it then waits for a signal that indicates an interrupt occured.
When signaled, the interrupt thread executes the required operations.
The interrupt thread releases control by waiting for the next signal from the interrupt handler,
which restarts the cycle shown in this figure.
Managing time
INtime software enables threads to:
• Create alarm events that wake up the current thread at a regular interval.
• Start and stop scheduling by the RT kernel.
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