SONIX SN8P2624 - 2.1.1.2 Interrupt Vector (0008 H)

SN8P2624
8-Bit Micro-Controller
SONiX TECHNOLOGY CO., LTD Page 14 Version 0.3
2.1.1.2 INTERRUPT VECTOR (0008H)
A 1-word vector address area is used to execute interrupt request. If any interrupt service executes, the program
counter (PC) value is stored in stack buffer and jump to 0008h of program memory to execute the vectored interrupt.
Users have to define the interrupt vector. The following example shows the way to define the interrupt vector in the
program memory.
 Note: ”PUSH”, “POP” instructions save and load ACC/PFLAG without (NT0, NPD). PUSH/POP buffer is a
unique buffer and only one level.
¾ Example: Defining Interrupt Vector. The interrupt service routine is following ORG 8.
.CODE
ORG 0 ; 0000H
JMP START ; Jump to user program address.
…
ORG 8 ; Interrupt vector.
PUSH ; Save ACC and PFLAG register to buffers.
…
…
POP ; Load ACC and PFLAG register from buffers.
RETI
; End of interrupt service routine
…
START: ; The head of user program.
… ; User program
…
JMP START ; End of user program
…
ENDP ; End of program