code: def swo_start(self, swo_speed=9600):
          
          if self.swo_enabled():
              self.swo_stop()
  
          info = structs.JLinkSWOStartInfo()
          info.Speed = swo_speed
          res = self._dll.JLINKARM_SWO_Control(enums.JLinkSWOCommands.START,
                                               ctypes.byref(info))
          if res < 0:
              raise errors.JLinkException(res)
  
          self._swo_enabled = True
  
          return None
docs: Starts collecting SWO data.
  
          Note:
            If SWO is already enabled, it will first stop SWO before enabling it
            again.
  
          Args:
            self (JLink): the ``JLink`` instance
            swo_speed (int): the frequency in Hz used by the target to communicate
  
          Returns:
            ``None``
  
          Raises:
            JLinkException: on error