An IrDA control method enabling communication by an optimum procedure without command collision even in an environment where plural host devices and plural peripheral devices exist. The plural host devices respectively have a unique back-off value, and the plural peripheral devices respectively have a unique back-off value. The respective devices perform an Enumeration procedure and a Bind procedure in accordance with the back-off value. Especially when another device is currently performing a series of Enumeration processing, transmission of response command is inhibited. Accordingly, command collision can be avoided, and as a result, communication efficiency and communication stability can be improved.