public static void led_branch(String num, String filepath, String sn, Scanner scanner){
		
		String line="", result = "";
		int item=0;
		System.out.println("Please choose the LED light you want to test: 1=white led, 2=rgb led, 0=return:");
		line=scanner.nextLine();
		while (!(line.equals("0"))){
			while ((!(line.equals("1")))&&(!(line.equals("2")))&&(!(line.equals("0")))){
				System.out.println("Error input! ");
				System.out.println("Please choose the LED light you want to test: 1=white led, 2=rgb led, 0=return:");
				line=scanner.nextLine();
			}
			if (line.equals("0")){
				break;
			}
			item = Integer.parseInt(line);
			switch(item){
			case 1:
				result = LED_White.serialcomm(num,scanner);
				LED_White.ledprocess(filepath, result, sn);
				break;
			case 2:
				result = LED_RGB.serialcomm(num,scanner);
				LED_RGB.ledprocess(filepath, result, sn);
				break;
			}
			System.out.println("Please choose the LED light you want to test: 1=white led, 2=rgb led, 0=return:");
			line=scanner.nextLine();
		}
			
	}