航標(biāo)燈控制程序

	ORG 0000H
	AJMP MAIN
	ORG 0003H
	AJMP WINT
	ORG 000BH
	AJMP T0INT
	ORG 0100H
 MAIN:	MOV SP,#30H
	CLR P1.7
	CLR IT0
	CLR PX0
	SETB EX0
	SETB EA
 HERE:	AJMP HERE
 WINT:	MOV TMOD,#01H
	MOV TL0,#0B0H
	MOV TH0,#3CH
	SETB PT0
	SETB TR0
	SETB ET0
	MOV R7,#40H
 HERE1: JNB P3.2,HERE1
	CLR ET0
	CLR TR0
	CLR P1.7
	RETI
 T0INT: MOV TL0,#0B0H
	MOV TH0,#3CH
 	DJNZ R7,EXIT
	MOV R7,#40H
	CPL P1.7
 EXIT:  RETI
	END