COMMUNICATION CONTROLLER FOR ID SYSTEM

摘要

PURPOSE:To always carry out communication despite arrival of any data carrier by outputting a special initial signal via each data carrier and demodulating the carrier signal to produce a synchronizing clock signal in response to the transmitting speed for execution of the subsequent communication tasks at the ID controller side. CONSTITUTION:A data carrier 40 receives the electric power from an ID controller 20 and outputs an initial signal which is modulated by a code having an 1:1 ON/OFF ratio. The controller 20 receives said modulated signal to demodulate it and divides this demodulated signal to output a demodulated signal having a double cycle via a decoding circuit. The counter of the controller 20 is replaced with reception of a pulse signal of a fixed frequency. Furthermore a synchronizing clock signal is outputted from a synchronizing clock signal generating circuit 26 in response to the contents of replacement of the counter. The controller 20 carries on the subsequent communication tasks by said synchronizing clock signal. Thus the proper communication is carried out with the data carriers regardless of their transmitting speeds.