Coded signaling and control system

A selective signaling and control system comprising first means for generating a start and reset signal at a first frequency;

• second means for generating a preselected code signal comprising a plurality of alternating tones at second and third frequencies;
• third means for generating an on/off latching signal at a frequency differing from said first, second and third frequencies;
• and fourth means coupled with said first, second, and third means for sequentially controlling the same to generate a composite coded message;
• wherein said second generating means comprises a pair of different frequency tone generators and shift means alternately enabling each of said tone generators;
• said shift means comprising a clock network, a shift/code flip-flop having a trigger input connected to an output of said clock network for periodically changing states in response to said clock output, and gate means coupled with the output of said shift/code flip-flop and said tone generators to alternately enable the same;
• said gate means comprising a first gate controlling the output of a first one of said tone generators and a second gate controlling the output of a second one of said tone generators, said first and second gates being responsive to said shift/code flip-flop;
• and a decade counter coupled with said shift/code flip-flop and said second gate through a patching network for controlling said second gate in accordance with a preprogrammed code.

In a selective signaling and control system, a transmitting circuit comprising

• a signal output network;
• first means for generating a start and reset signal at a first frequency;
• second means for generating a signal at a second frequency;
• third means for generating a code bit signal at a third frequency;
• first, second, and third gate means connected to said first, second and third generating means, respectively, for coupling the outputs thereof to an input of said signal output network,
• a programmable decade counter coupled at an output to said first and third gate means for opening and closing said first and third gate means in a preselected sequence thereby to control the presence and absence, respectively, of said first and third frequency tones at the input of said signal output network;
• and
• clock controlled switching means coupled to said first, second and third gate means and said decade counter for alternately enabling and disabling said second gate means and said decade counter whereby the signal fed to said signal output network consists of a series of tone bursts comprising said second frequency tone alternated with a first or third frequency tone as enabled by said decade counter.

In a selective signaling and control system, a receiving circuit comprising

• first means responsive to a start and reset signal at a first frequency for providing a sequence start signal;
• second means coupled to said first means and responsive to a series of alternating tones at second and third frequencies, respectively, when said sequence start signal is provided, for storing each of said received third frequency tone signals as a separate data bit at a serial position sequentially advance by each received second frequency tone signal;
• means comparing said stored data bit signals with a preselected code and generating an output when the two are equal;
• and
• control means enabled in response to the output of said comparing means to respond to a tone signal at a fourth frequency to contol an output device.