10-2-1.asm

书籍8051入门篇

;10-2-1.ASM
$MOD51
	ORG	0000H
	LJMP	START		; MAIN PROGRAM
	ORG	000BH
	LJMP	T0_ISR		; TIMER0 INTERRUPT
;
	ORG	0030H
START:	SETB	P1.0		; INITIALIZE P1.0 = 1
	MOV	TMOD,#11H	; TIMER0 = MODE1
	MOV	TH0,#0DBH	; (65536-9217) / 256
	MOV	TL0,#0FFH	; (65536-9217) % 256
	CLR	TF0		; CLEAR TF0 FLAG
	SETB	TR0		; START TIMER0
	SETB	ET0		; ENABLE TIMER0 INTERRUPT
	SETB	EA		; START INTERRUPT
LOOP:	SJMP	LOOP
;
T0_ISR: CPL	P1.0		; CPL P1.0
	CLR	TF0		; CLEAR TF0 FLAG
	MOV	TH0,#0DBH	; (65536-9217) / 256
	MOV	TL0,#0FFH	; (65536-9217) % 256
	RETI			; RETURN FROM INTERRUPT
	END