Code:
PROCESSOR 16F877A
INCLUDE <P16F877A.INC>
;**************************
COUNT1 EQU 28h ; ban phai dat dia chi o day
COUNT2 EQU 29h ; 0x08,0x09,0x0A se trung voi
COUNT3 EQU 2AH ; cac thanh ghi dac biet
;**************************
ORG 0X000 ;Dia chi Flash bat dau
GOTO MAIN
ORG 0X005 ;Dat chuong trinh o day de tranh di chi ngat (0x004)
MAIN
BSF STATUS,RP0
CLRF TRISB
BCF STATUS,RP0
START
MOVLW d'18'
MOVWF PORTB
CALL DELAY
MOVLW d'0'
MOVWF PORTB
CALL DELAY
GOTO START
;**************************
DELAY ; chuong trinh con phai dat o day
LOOP1
DECFSZ COUNT1,1
GOTO LOOP1
DECFSZ COUNT2,1
GOTO LOOP1
DECFSZ COUNT3,1
GOTO LOOP1
RETURN
END
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