11-17-1.asm

书籍8051入门篇

;11-17-1.ASM
$MOD51
	ORG	0000H
	SJMP	START
	ORG	0023H
	SJMP	SERIAL
;
	ORG	0030H
START:	MOV	TMOD,#21H
	MOV	TH1,#0FDH
	SETB	TR1
	MOV	SCON,#50H
	MOV	R1,#0
	SETB	ES
	SETB	EA
	SETB	TI
STOP:	SJMP	STOP
;
SERIAL:	JNB	RI,NEXT
	CLR	RI
	MOV	A,SBUF
	CPL	A
	MOV	P1,A
NEXT:	JNB	TI,EXIT
	CLR	TI
	ACALL	DELAY
	MOV	A,R1
	MOV	SBUF,A
	INC	R1
EXIT:	RETI
;
DELAY:	MOV	R2,#0
L1:	MOV	R3,#0
	DJNZ	R3,$
	DJNZ	R2,L1
	RET
	END