Data carrier having option means

A data carrier including an electrical circuit, which circuit has

• receiving means adapted to supply input data, which input data may include an option control command, and
• option control command processing means to which the option control command can be applied and which are adapted to generate a port control command in dependence on the option control command, and
• port means to which the port control command can be applied and which can be set from one port state into another port state, which is complementary to said one port state, in dependence on the port control command, and
• at least one option means which is optionally accessible to at least a command processing means with the aid of the port means in dependence on the port states,
• characterized in that the option control command processing means are adapted to process at least one pair of mutually complementary option control commands and to generate at least one pair of mutually complementary port control commands, and the port means can be controlled reversibly as regards their port states in dependence on the two mutually complementary port control commands.