ORG		00H
START:	MOV		A,#0FEH		;設(shè)置輸出初值
		SETB	C			;進位標志置1
S1:		MOV		P1,A	   	;輸出A值
		LCALL	DELAY
		RLC		A		 	;A帶進位右移
		JC		S1		   	;若移位次數(shù)達到8次,重設(shè)輸出初值
		MOV		A,#7FH
		SETB	C
S2:		MOV		P1,A		;將新的A值輸出
		LCALL	DELAY
		RRC		A
		JC		S2
		LJMP	START
DELAY:	MOV		R5,#20	 	;延時子程序
D1:		MOV		R6,#20
D2:		MOV		R7,#248
		DJNZ	R7,$
		DJNZ	R6,D2
		DJNZ	R5,D1
		RET
		END