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CHAPTER 11 EXTERNAL INTERRUPT CIRCUIT 2 (LEVEL)
11.7
Program Example for External Interrupt Circuit 2
An example of programming external interrupt circuit 2 is given below.
■
Program Example for External Interrupt Circuit 2
●
Processing specification
The external interrupt circuit 2 detects an "L" level signal input to the P00/INT20/AN4 pin and generates
an interrupt.
●
Coding example
DDR0
EQU
0001H
; Address of the port data direction register
ADEN
EQU
0034H
; Address of the A/D enable register
EIE2
EQU
0036H
; Address of the external interrupt 2 control register
EIF2
EQU
0037H
; Address of the external interrupt 2 flag register
IF20
EQU
EIF2:0
; Definition of the external interrupt request flag bit
ILR3
EQU
007DH
; Address of the interrupt level setting register
INT_V DSEG
ABS
; [DATA SEGMENT]
ORG
0FFE6H
IRQA
DW
WARI
; Interrupt vector setting
INT_V ENDS
;------------------------Main program--------------------------------------------------------------------------------
CSEG
; [CODE SEGMENT]
; Stack pointer (SP) is assumed to have been initialized.
:
;
CLRI
; Disable interrupts.
CLRB
IF20
; Clear external interrupt request flag.
MOV
ILR2,#11111110B
; Set interrupt level to 2.
MOV
DDR0,#00000000B
; Set pin INT20/AN4 to serve inputs only.
MOV
ADEN,#00000000B
; Set pin INT20/AN4 to enable external interrupt inputs.
MOV
EIE2,#00000001B
; Enable external interrupt inputs to pin INT20/AN4.
SETI
; Enable interrupts.
:
;------------------------Interrupt processing routine----------------------------------------------------------------
WARI
MOV
EIE2,#00000000B
; Disable external interrupt inputs to pin INT20/AN4.
CLRB
IF20
; Clear external interrupt request flag.
Summary of Contents for F2MC-8L F202RA
Page 2: ......
Page 4: ......
Page 32: ...16 CHAPTER 1 OVERVIEW ...
Page 90: ...74 CHAPTER 3 CPU ...
Page 142: ...126 CHAPTER 5 TIME BASE TIMER POPW A RETI ENDS END ...
Page 150: ...134 CHAPTER 6 WATCHDOG TIMER ...
Page 176: ...160 CHAPTER 7 8 BIT PWM TIMER ...
Page 220: ...204 CHAPTER 8 8 16 BIT CAPTURE TIMER COUNTER ...
Page 240: ...224 CHAPTER 9 12 BIT PPG TIMER ...
Page 274: ...258 CHAPTER 11 EXTERNAL INTERRUPT CIRCUIT 2 LEVEL ...
Page 362: ...346 CHAPTER 15 BUZZER OUTPUT ...
Page 390: ...374 CHAPTER 17 FLASH MEMORY ...
Page 419: ...403 INDEX INDEX The index follows on the next page This is listed in alphabetic order ...
Page 434: ...418 INDEX ...
Page 436: ......