The G12T interferometer on Plateau de Calern

We describe in this article the current status of the Grand Interferometre a 2 telescopes at the Observatoire de la Cote d'Azur in the south of France, near Grasse. After describing the 1.5 m telescopes and their control systems, we give details about the particular beam recombination and the focal instrumentation currently used. With the description of the data acquisition systems, we discuss the processing part of the GI2T work, which is presented in a subsequent article