A test mode signal system includes: a test mode block for generating a plurality, N, of test mode signals; a test mode send block, for generating and outputting a pulsed signal according to a command signal, and for multiplexing the N test mode signals in sets according to the pulsed signal and outputting the multiplexed pairs of test mode signals over M signal wires wherein M is less than N, such that each signal wire carries a multiplexed set of the N test mode signals; and a test mode receive block, for receiving the multiplexed sets of N test mode signals and the pulsed signal and demultiplexing each multiplexed set of N test mode signals according to the pulsed signal.