Program Example For External Interrupt Circuit 2 - Fujitsu F2MC-8L Series Hardware Manual

CHAPTER 11 EXTERNAL INTERRUPT CIRCUIT 2 (LEVEL)

11.7 Program Example for External Interrupt Circuit 2

This section provides a program example for external interrupt circuit 2.
Program Example for External Interrupt Circuit 2
Processing description
Generates an interrupt on detection of an "L" level signal input to the INT20 pin.
Coding example
DDR0 EQU
EIE2 EQU
EIF2 EQU
IF20 EQU
ILR3 EQU
INT_V DSEG
ORG
IRQA DW
INT_V ENDS
;-----Main program--------------------------------------------------------------------------------------------------------------------------------------
CSEG
:
CLRI
CLRB
MOV
MOV
MOV
SETI
:
;-----Interrupt handler-----------------------------------------------------------------------------------------------------------------------------------
258
0001H
0032H
0033H
EIF2:0
007EH
ABS
0FFE6H
WARI
IF20
ILR3, #11101111B
DDR0, #00000000B
EIE2, #00000001B
; Address of port direction register
; Address of external interrupt 2 control register
; Address of external interrupt 2 flag register
; Define external errupt request flag bit.
; Address of interrupt level setting register
; [DATA SEGMENT]
; Set interrupt vector.
; [CODE SEGMENT]
; Initialize stack pointer (SP) etc.
;
; Disable interrupts.
; Clear external interrupt request flag.
; Set interrupt level to 2.
; Set INT20 pin as input pin.
; Enable INT20 pin for external interrupt input.
; Enable interrupts.