Fujitsu FR30 Computer Hardware User Manual


 
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CHAPTER 8 INTERRUPT CONTROLLER
8.6 Returning from the Standby Mode (Stop/Sleep)
This module implements the function to return from standby mode when an interrupt
request is issued.
Returning from Standby Mode (Stop or Sleep State)
When a peripheral interrupt request including NMI occurs, a request to return from standby
mode is issued to the clock controller.
The priority check block restarts operation when clock pulses are supplied after returning from
the stop state. Therefore, the CPU executes instructions until the priority check block outputs
the check result.
The same operations are performed for returning from the sleep state.
In the sleep state, the register in this module can be accessed using DMAC.
<Notes>
An NMI request also causes a return from the stop state.
For an interrupt cause that should not trigger a return from the stop or sleep state, use the
corresponding peripheral control register to inhibit the output of the interrupt request. Since
the signal for requesting a return from the standby mode is the output of a simple logical sum
of all interrupt causes, the interrupt level set in the ICR is not used.
To perform DMA transfer in the sleep state, make settings in the DMA side to ensure that no
interrupt request is posted to this module and that a return from the sleep state does not
occur accidentally.