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15 interrupt management function – Renesas Emulator System M3T-MR100 User Manual

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4.1.15

Interrupt Management Function

The interrupt management function provides a function to process requested external interrupts in real time.

The interrupt management service calls provided by the MR100 kernel include the following:

Returns from interrupt handler (ret_int)

The ret_int service call activates the scheduler to switch over tasks as necessary when returning from the interrupt
handler.
When using the C language,

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, this function is automatically called at completion of the handler function. In this

case, therefore, there is no need to invoke this service call.

Figure 4.25 shows an interrupt processing flow. Processing a series of operations from task selection to register restoration
is called a "scheduler.".

Interrupt

TaskA

Save Registers

Handler Processing

iwup_tsk

ret_int

Task Selection

Restore Registers

TaskB

#pragma INTHANDLER Declare
(C language)

Figure 4.25 Interrupt process flow

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In the case that the interruput handler is specified by "#pragma INTHANDLER".