Operation Of Status Flags For Level-Detected Interrupts - Renesas RX100 Series User Manual

RX13T Group
14.4.1.2

Operation of Status Flags for Level-Detected Interrupts

Figure 14.5 shows the operation of the interrupt status flag (IR flag) in IRn (n = interrupt vector number) in the case of
level detection of an interrupt from a peripheral module or an external pin.
The IR flag in IRn remains set to 1 as long as the interrupt signal is asserted. To clear the IRn.IR flag to 0, clear the
interrupt request in the source generating the interrupt. Confirm that the interrupt request flag in the source generating the
interrupt has been cleared to 0 and that the IRn.IR flag has been cleared to 0, and then complete the interrupt handling.
Interrupt signal
System clock
IRn.IR flag
Figure 14.5 IRn.IR Flag Operation for Level Detection Interrupts
Figure 14.6 shows the procedure for handling level detection interrupts.
Interrupt has not been generated
Confirm IRn.IR flag
IRn.IR = 0
End of interrupt handling
Figure 14.6 Procedure for Handling Level Detection Interrupts
R01UH0822EJ0100 Rev.1.00
Jul 31, 2019
Start interrupt handling
Confirm interrupt
request source
IRn.IR = 1
Perform interrupt request source processing
14. Interrupt Controller (ICUb)
Interrupt has been generated
Clear interrupt request source
Page 224 of 1041