Earlier versions of these transmissions that are semi-automatic in operation, such as "Autostick", only control the clutch system automatically — and use different forms of actuation (usually via an actuator or servo) to automate the clutch, but still require the driver's input and full control to manually actuate gear changes by hand. Modern versions of these systems that are fully-automatic in operation, such as "Selespeed" and "Easytronic", require no driver input over gear changes or clutch operation. Semi-automatic versions only require partial driver input (i.e., the driver must changing gears manually), while fully-automatic versions require no manual driver input, whatsoever (TCU or ECU operates both the clutch system and gear shifts automatically).