2016/12/04 04:00:07 - IOError: [Errno 2] No such file or directory: '/dev/ttyUSB4'
2016/12/04 04:00:59 - <class 'uhdas.serial.sp_lock.LockedError'> Exception in Tk callback
  Function: <bound method StartStopControl.C_start of <pycurrents.system.startstop.StartStopControl instance at 0x7fe6ab3fb368>> (type: <type 'instancemethod'>)
  Args: ()
Traceback (innermost last):
  File "/usr/lib/python2.7/dist-packages/Pmw/Pmw_1_3/lib/PmwBase.py", line 1747, in __call__
    return apply(self.func, args)
  File "/usr/local/lib/python2.7/dist-packages/pycurrents/system/startstop.py", line 70, in C_start
    self.funcs[0](**kw)
  File "/usr/local/lib/python2.7/dist-packages/uhdas/uhdas/DAS.py", line 373, in StartLogging
    t.wakeup()
  File "/usr/local/lib/python2.7/dist-packages/uhdas/serial/oswh_term.py", line 155, in wakeup
    self.slow_wakeup()
  File "/usr/local/lib/python2.7/dist-packages/uhdas/serial/oswh_term.py", line 111, in slow_wakeup
    self.change_baud(self.default_baud)
  File "/usr/local/lib/python2.7/dist-packages/uhdas/serial/tk_terminal.py", line 527, in change_baud
    self.open_port(save=False)
  File "/usr/local/lib/python2.7/dist-packages/uhdas/serial/serialport.py", line 72, in open_port
    sp_lock.lock_port(self.__device)  # Raises exception if locked.
  File "/usr/local/lib/python2.7/dist-packages/uhdas/serial/sp_lock.py", line 74, in lock_port
    check_lock(device)
  File "/usr/local/lib/python2.7/dist-packages/uhdas/serial/sp_lock.py", line 71, in check_lock
    raise LockedError(status, device)
<class 'uhdas.serial.sp_lock.LockedError'>: (1, '/dev/ttyUSB4')