Sony CXD5602 User Manual page 109

interrupts INT_EN*, refer to 3.3.2 (Chapter of Interrupt).
1. Mask an interrupt.
INT_EN0.EXDEVICE[0] = 0
2. Set the Event Detection (Pin Multiplexer, I/O pin selection, and way of detecting events).
3. Clear status register of Event Detection (to avoid errors caused by the result of the previous event
detection).
PMU_WAKE_TRIG0_CLR.SYSGPI0 = 1
4. Wait for the completion of clearing the status register of Event Detection.
Confirm that PMU_WAKE_TRIG0_CLR.SYSGPI0 = 0.
5. Cancel interrupt masking.
INT_EN0.EXDEVICE = 1
Flow of Clearing Event Detection
For example, the flow of clearing an interrupt (EXDEVICE[0]) is described below.
1. Detect an event detection as an interrupt.
2. Mask an interrupt.
INT_EN0.EXDEVICE[0] = 0
3. Clear the status register of Event Detection.
PMU_WAKE_TRIG0_CLR.SYSGPI0 = 1
4. Wait for the completion of clearing the status register of Event Detection.
Confirm that PMU_WAKE_TRIG0_CLR.SYSGPI0 equals 0.
5. Cancel interrupt masking (only when you want to detect an interrupt again)
INT_EN0.EXDEVICE[0] = 1
Restriction on Clearing Events
Clearing process to clear a held event is performed when 1 is set on any bit of PMU_WAKE_TRIG0_CLR. You
cannot start a new clearing while the former one is still in process. That is, if you set 1 on other bit of
PMU_WAKE_TRIG0_CLR while the former clearing is still in process, you must wait for the new clearing until
the former one ends. However, if you set 1 on multiple bits at a time, multiple clearing processing can be
performed in parallel.
For example, if you set 1 on PMU_WAKE_TRIG0_CLR and then set 2 or 3 on it, clearing processing of
SCU_INT0 cannot start until clearing process of CRG_INT ends.
If you set 3 on PMU_WAKE_TRIG0_CLR, clearing processing of both CRG_INT and SCU_INT0 can be
performed in parallel.
Time Interval for a Signal to be Able to Detect an Event Again
Once a signal from I/O pin (external signal) is received to detect an event, the same one from I/O pin will ignore
further events until the detected event is cleared. Table General Purpose Input/Output (GPIO)-31 shows time
intervals from event detection to the next event detection through the flow of clearing the result of event detection.
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CXD5602 User Manual