Registers Controlling Interrupt Functions - NEC 78K0 User Manual

(C) External maskable interrupt (INTKR)
Interrupt
request
1 when KRMn = 1 (n = 0 to 7)
(D) Software interrupt
IF: Interrupt request flag
IE: Interrupt enable flag
ISP: In-service priority flag
MK: Interrupt mask flag
PR: Priority specification flag
KRM: Key return mode register

15.3 Registers Controlling Interrupt Functions

The following 6 types of registers are used to control the interrupt functions.
• Interrupt request flag registers (IF0L, IF0H, IF1L)
• Interrupt mask flag registers (MK0L, MK0H, MK1L)
• Priority specification flag registers (PR0L, PR0H, PR1L)
• External interrupt rising edge enable register (EGP)
• External interrupt falling edge enable register (EGN)
• Program status word (PSW)
Table 15-2 shows a list of interrupt request flags, interrupt mask flags, and priority specification flags corresponding
to interrupt request sources.
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CHAPTER 15 INTERRUPT FUNCTIONS
Figure 15-1. Basic Configuration of Interrupt Function (2/2)
Internal bus
MK
Key
IF
interrupt
detector
Interrupt
Priority controller
request
User's Manual U16227EJ2V0UD
IE PR ISP
Vector table
Priority controller
address generator
Internal bus
Vector table
address generator
Standby release signal