书籍8051入门篇

				;PROGRAM NAME:12-5-1.ASM
				BUFFER	DATA	20H
				$MOD51
					ORG	0000H
					MOV	SP,#50H		;设定堆栈STACK
					MOV	A,#00H		;累加器=00H
					MOV	BUFFER,A	;(20H)=00H
				LOOP:	MOV	P1,BUFFER	;P1=(BUFFER)
					INC	BUFFER		;P1=BUFFER内容加上1
					LCALL	DELAY		;延迟一小段时间
					SJMP	LOOP
				;ROUTINE
				;单纯时间延迟用
				DELAY:	MOV	R0,#00H
				DLY:	MOV	R1,#00H	
					DJNZ	R1,$
					DJNZ	R0,DELAY
					RET
					END