Code Mplab

[david]

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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