串口指令:
"+ command -+ syntax -----+ function ---------
"| Display | D | display times 例:D\n
"| Quit |ESC(0x1B)or Q| Quit display times 例:Q
"| Time | T hh:mm:ss | set clock time 例:T 10:00:00\n
"| Start | S hh:mm:ss | set start time 例:S 10:01:00\n
"| End | E hh:mm:ss | set end time 例:E 10:02:00\n