 The RC-5 command set was defined in the late 1980s and expanded to increase the number of commands in the early 1990s (sometimes called RC-5x).However, the rapidly expanding requirements for newer categories of electronics products since that time (e.g., DVD players, cable boxes, DVR's, et cetera) has led Philips to replace the RC-5 protocol with the newer RC-6 protocol that has both an expanded set of devices (256 versus 32) and commands per device (256 versus 64 in RC-5 and 128 in RC-5x).Again, information on the RC-6 protocol is not readily available from Philips.