NEC mPD789026 Subseries, User Manual

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User's Manual U11919EJ3V0UM00
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CHAPTER 10 INTERRUPT FUNCTIONS
10.1 Interrupt Function Types
The following two types of interrupt functions are used.
(1) Non-maskable interrupt
This interrupt is acknowledged unconditionally. It does not undergo interrupt priority control and is given top
priority over all other interrupt requests.
A standby release signal is generated.
The non-maskable interrupt has one source of interrupt from the watchdog timer.
(2) Maskable interrupt
These interrupts undergo mask control. If two or more interrupts are simultaneously generated, each
interrupt has a predetermined priority (priority) as shown in Table 10-1.
A standby release signal is generated.
The maskable interrupt has four sources of external interrupts and five sources of internal interrupts.
10.2 Interrupt Sources and Configuration
There are total of ten non-maskable and maskable interrupts in the interrupt sources (see Table 10-1).