HD404618 Datasheet, PDF (22/91 Pages) Hitachi Semiconductor – 4-Bit Single-Chip Microcomputer

HD404618 Series
Power
on
No
RESET = 1 ?
Yes
Reset MCU
Interrupt Yes
request ?
No
Execute instruction
No
IE = 1?
Yes
Accept interrupt
PC ^←(PC) + 1
IE ←0
Stack ← (PC)
Stack ← (CA)
Stack ^← (ST)
PC^← $0002
PC^← $0004
PC^← $0006
PC^← $0008
Yes
INT₀
interrupt ?
No
Yes
INT₁
interrupt ?
No
Yes Timer A
interrupt ?
No
Yes Timer B
interrupt ?
PC^← $000A
No
Yes Timer C
interrupt ?
No
PC^←$000C
(serial interrupt)
Figure 9 Interrupt Processing Flowchart
20