Car-use extended device and setting method for operation interface of car-use control system

A car-use extended device being applied to electrically communicate to a car-use audio to from a car-use control system, so as to use the car-use control system to simulate a user-to-machine operation interface for controlling an electronic computing device installed with an operation system to execute as least one preset assignment;

• the car-use audio comprising an operation interface, which comprises a trigger element and at least one working signal input element;
• the triggering element generating a triggering signal after being triggered;
• and the car-use extended device comprising:
• a micro control unit being electrically communicated to the operation interface for receiving the triggering signal, and comprising:
• an interface-function setting program for defining at least one preset assignment that the working signal input element represents after the micro control unit receiving the triggering signal, so as to simulate the user-to-machine operation interface;
• wherein when the trigger element and the working signal input element are triggered in turn, the micro control unit outputs a working signal to the electronic computing device in accordance with the preset assignment that the working signal input element represents, so as to control the electronic computing device to execute the preset assignment.