The STI-4 driver is a basic driver type that is designed for use in standard passenger information systems and serves to control the external (front, numeric lateral) and internal boards as well as ticket validators. It enables the projection of destination names on the boards. The driver is equipped with a large back-lit LCD screen and a convenient silicone keyboard.

The search of a destination is carried out as follows: scrolling and selection of the destination searched (presentation file) from the list. The programming of the driver is carried out by means of an SD card. The presentation to be projected on boards is prepared by means of a dedicated computer program created with the „ResEditor” application. The driver enables the following parameter settings: the number of ticket validators installed in a vehicle, the vehicle number, the arrangement of digits printed on paper tickets. There are also regular diagnostic processes to control ticket validator condition and if any irregularity is diagnosed, error signalling takes place.