Fujitsu F2MC-8FX Hardware Manual page 315

How to enable/disable/clear interrupts
Interrupt request enable flag, Interrupt request flag
The interrupt request enable bit (PCNTL0 IREN) is used to enable interrupts.
What to be controlled
When disabling interrupt request
When enabling interrupt request
The interrupt request flag (PCNTL0 IRQF) is used to clear interrupt requests.
What to be controlled
When clearing interrupt request
CHAPTER 17 16-BIT PPG TIMER
Interrupt request enable bit (IREN)
Set the bit to "0"
Set the bit to "1"
Interrupt request flag (IRQF)
Write "0" to the bit
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