def _controller_buffer(self, port):
<EOL>address = _LIB.Controller(self._env, port)<EOL>buffer_ = ctypes.cast(address, ctypes.POINTER(CONTROLLER_VECTOR)).contents<EOL>return np.frombuffer(buffer_, dtype='<STR_LIT>')<EOL>
Find the pointer to a controller and setup a NumPy buffer.

Args:
    port: the port of the controller to setup

Returns:
    a NumPy buffer with the controller's binary data