String aa = "91H,03H,00H,00H,2AH";//把要发送的指令赋给aa
outputStream = serialPort.getOutputStream();
outputStream.write(aa.getBytes());//把指令发送出去aa.getBytes 后变为 [B@1f78b68 了,这只是部分代码,怎么样能让outputStream.write的参数是91H,03H,00H,00H,2AH  ??