Some new protocols handle time constraints to model important aspects (delays, timeouts, ..). This issue has to be taken into account in every step during its development life cycle, in particular in the testing step. This paper presents an integrated tool which permits to specify a timed system in various models (RT-LOTOS, IF, Timed automata) and then generates test sequences using a new efficient algorithm. Illustrated examples show the differents steps of this new test generation method.