A control device in a vehicle, which control device is connected to, and is for operating, a semi-automatic gearbox, can be set in various gearchange function positions and can, in at least one gearchange function position for traveling forwards, be operated for gear changing. The control device is also connected to, and is for operating, a supplementary brake. This control device replaces both the gear lever and the supplementary brake lever, resulting in increased driving safety and better ergonomics for the driver.