10-8-1.asm

书籍8051入门篇

;10-8-1.ASM
$MOD51
MS10		EQU	-9217
TMH		EQU	(MS10) / 256
TML		EQU	(MS10) MOD 256
KEY		BIT	P3.4
CNT		DATA	030H
;
		ORG	0000H
		LJMP	START
		ORG	000BH
		LJMP	T0_ISR
;
		ORG	0030H
START:		SETB	KEY
		MOV	CNT,#0
		MOV	TMOD,#11H
		MOV	TL0,#TML
		MOV	TH0,#TMH
		CLR	TF0
		SETB	TR0
		SETB	ET0
		SETB	EA
LOOP:		JB	KEY,LOOP
		JNB	KEY,$
		INC	CNT
		ACALL	DELAY
		SJMP	LOOP
;
DELAY:		MOV	R0,#100
L1:		MOV	R1,#0
		DJNZ	R1,$
		DJNZ	R0,L1
		RET
;	
T0_ISR:		MOV	TL0,#TML
		MOV	TH0,#TMH
		MOV	A,CNT
		CPL	A
		MOV	P1,A
		RETI
		END