Preliminary User’s Manual U16846EJ1V0UD
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CHAPTER 14 INTERRUPT FUNCTIONS
14.1 Interrupt Function Types
The following two types of interrupt functions are used.
(1) Maskable
interrupts
These interrupts undergo mask control. Maskable interrupts can be divided into a high interrupt priority group
and a low interrupt priority group by setting the priority specification flag registers (PR0L, PR0H, PR1L).
Multiple interrupt servicing of high-priority interrupts can be applied to low priority interrupts. If two or more
interrupts with the same priority are simultaneously generated, each interrupt is serviced according to its
predetermined priority (see Table 14-1).
A standby release signal is generated and the STOP mode and HALT mode are released by maskable interrupts.
Six external interrupt requests and 12 internal interrupt requests are provided as maskable interrupts.
(2) Software
interrupt
This is a vectored interrupt generated by executing the BRK instruction. It is acknowledged even when interrupts
are disabled. The software interrupt does not undergo interrupt priority control.
14.2 Interrupt Sources and Configuration
A total of 19 interrupt sources exist for maskable and software interrupts. In addition, maximum total of 5 reset
sources are also provided (see Table 14-1).