Data communication system for activating remote loads

Abstract

A data communication system for selectively activating a plurality of remote loads. The system includes a transmitter having an encoder with first and second sets of inputs. The encoder provides a multi-bit pulse train for transmission to a receiver. Selected bits of the pulse train are associated with the first set of inputs to the encoder and define an address code. Other bits of the transmitted pulse train are associated with the second set of encoder inputs and define data. A receiver incorporates a decoder coupled for receipt of the pulse train from the transmitter. A set of code select inputs for the decoder defines a local address code for the receiver. A pulse generator provides a local pulse train which is a function of the code select inputs. A comparator normally operates to compare all of the bits in the local pulse train with those in the received pulse train from the transmitter, with the comparator output preventing load actuation unless all of the bits match. However, logic circuitry is provided for selectively preventing the comparator from comparing the bits in the received pulse train defining data with corresponding bit positions in the local pulse train. Selected loads are then activated according to the states of the data bits in the received pulse train if the address code portions of the local and received pulse trains match.