Sorry, I actually meant aircraft type. The ADIRU(s) and associated interface with the TCAS Computer will be dependant on the type of aircraft.
Without knowing which type(s) of aircraft it's difficult to answer.
I would hazard a guess however, that the TCAS Computer is set-up in such a way that it receives inputs from ADIRU #1 and thus if ADIRU #1 was to fail, the TCAS would also fail.