HD404654 Datasheet, PDF (22/111 Pages) Hitachi Semiconductor – 4-Bit Single-Chip Microcomputer

HD404654 Series
Power on
RESET = 0?
No
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^← $000A
PC^←$000C
PC^← $000E
Yes
INT₀
interrupt?
No
Yes
INT₁
interrupt?
No
Yes
Timer-A
interrupt?
No
Yes
Timer-C
interrupt?
No
Yes
Timer-D
interrupt?
No
(serial 1 interrupt)
Figure 10 Interrupt Processing Flowchart
20