In accordance with the ERTMS/ETCS specifications (mainly Subset 026 and ERA_ERTMS_015560 document), UIC 612 leaflet, EN 50126 (series), EN 16186 (series) and EN 61375 (series) requirements, this Technical Report describes the Train Display System (TDS) in the driver s cab which comprises the Train Display Controller (TDC) and the following six interfaces: Interface with Command Control Display (CCD), Interface with Train Radio Display (TRD), Interface with Electronic Timetable Display (ETD), Interface with Technical and Diagnostic Display (TDD), Interface with ETCS Onboard systems and the interfaced STMs, which is excluded from the scope of this document, Interface with Other Onboard Systems. NOTE Dotted lines are not described by this document. The scope of this document is to define the functional architecture around the (TDC). This document excludes the following items: Communication protocols (e.g. EN 61375 series); Ergonomic aspects; Interface with ETCS Onboard systems and the interfaced STMs; Train functions; GSM-R EIRENE functions; Use of the displays as terminals for maintenance purpose.