A control method and a control device are provided. A router receives data sent by a first device, where the data carries an identifier of an input/output (I/O) device, determines, according to the identifier of the I/O device and a correspondence between the I/O device and a controller, a controller corresponding to the identifier of the I/O device, sends the data to the controller corresponding to the identifier of the I/O device such that the controller processes the data according to firmware code stored in the controller, receives the processed data sent by the controller, and sends the processed data to a second device, where the second device or the first device is the I/O device. The firmware code is generally programmable, and therefore a control device applying the foregoing control method can be relatively flexibly implemented.