bus2oo2.asm

用单片机实现的总线比较的2取2功能的安全计算机

ORG     0000H
	LJMP    MAIN

	ORG     0030H

	MOV     P1,#0FFH
        SETB    P3.0
        SETB    P3.1
        SETB    P3.2
        SETB    P3.3
        SETB    P3.4
        SETB    P3.5

MAIN:   
        XRL     P1,#0FFH
        CPL     P3.0
        CPL     P3.1
        CPL     P3.2
        CPL     P3.3
        CPL     P3.4
        CPL     P3.5
	MOV     DPTR,#8000H
	MOVX    A,@DPTR
	ANL	A,#03H
	MOV     30H,A

	MOV     DPTR,#0C000H
	MOVX    A,@DPTR
	ANL	A,#03H
        CJNE    A,30H,LOOP1

	CJNE    A,#01H,LOOP0		
	MOV	A,#01H		;绿灯亮
	MOV     DPTR,#8000H
	MOVX    @DPTR,A

	MOV	A,#01H		;绿灯亮
	MOV     DPTR,#0C000H
	MOVX    @DPTR,A
        
	LJMP	MAIN

LOOP0:	CJNE    A,#02H,LOOP1		
	MOV	A,#02H		;黄灯亮
	MOV     DPTR,#8000H
	MOVX    @DPTR,A

	MOV	A,#02H		;黄灯亮
	MOV     DPTR,#0C000H
	MOVX    @DPTR,A
	LJMP	MAIN

LOOP1:	MOV	A,#04H		;红灯亮
	MOV     DPTR,#8000H
	MOVX    @DPTR,A

	MOV	A,#04H		;红灯亮
	MOV     DPTR,#0C000H
	MOVX    @DPTR,A
        LJMP	MAIN


END