pctongxin.asm

关于RS232的,希望对你有帮助,

	ORG	0
	ORG	30H
STAR:	MOV	TMOD,#20H
	MOV	PCON,#0
	MOV	TH1,#0E6H
	MOV	TL1,#0E6H
	SETB	TR1
	CLR 	ES
	MOV	SP,#5FH
LOOP:	MOV	SCON,#50H
	JNB	RI,$
	CLR	RI
	MOV	A,SBUF
	PUSH	ACC
	//SJMP	STAR
	CJNE	A,#30H,RANG1
RANG1:	JC	RANG3
	CJNE	A,#3AH,RANG2
RANG2:	JNC	RANG3
	CLR 	C
	SUBB	A,#30H
RANG3:	MOV	P1,A
	POP	ACC
RANG4:	NOP
	NOP
	NOP
	NOP
	NOP
	MOV	SBUF,A
	JNB	TI,$
END