Reversible counter operative to count either binary or binary coded decimal number system

Claim 1

IN PULSE COUNTING APPARATUS OPERATIVE WITH INPUT SIGNALS HAVING A LEADING AND A TRAILING EDGE, THE COMBINATION OF A PLURALITY OF BISTABLE COUNTING STAGES, WITH EACH OF SAID COUNTING STAGES BEING PROVIDED FOR A DIFFERENT BINARY DIGIT OF A NUMBER OF INPUT PULSES TO BE COUNTED AND INCLUDING INPUT AND OUTPUT TERMINALS AND HAVING AT LEAST TWO STATES OF OPERATION WHEREIN ZERO AND ONE OUTPUT SIGNALS ARE RESPECTIVELY PROVIDED AT SAID OUTPUT TERMINAL, A PLURALITY OF GATING CIRCUITS CONNECTED RESPECTIVELY BETWEEN THE OUTPUT TERMINAL OF EACH COUNTING STAGE AND THE INPUT TERMINAL OF THE NEXT ADJACENT COUNTING STAGE SUCH THAT SAID INPUT PULSES ARE SUCCESSIVELY COUNTED BY SAID PLURALITY OF COUNTING STAGES, CONTROL MEANS OPERATIVELY CONNECTED BETWEEN EACH OF SAID COUNTING STAGES AND SAID GATING CIRCUITS, SAID CONTROL MEANS BEING OPERATIVE TO PROVIDE SPIKE SIGNALS OF DIFFERENT POLARITIES IN RESPONSE TO THE LEADING AND TRAILING EDGES RESPECTIVELY OF THE OUTPUT SIGNALS FROM THE PRECEDING GATING ELEMENT, AND A BIAS VOLTAGE SOURCE OPERATIVE TO PROVIDE A FIRST CONTROL SIGNAL FOR PROVIDING A FIRST PREDETERMINED COUNTING OPERATION IN RESPONSE TO SPIKE PULSES OF ONE POLARITY BEING SENSED AND HAVING A SECOND CONTROL SIGNAL FOR PROVIDING A SECOND PREDETERMINED COUNTING OPERATION WHEN SPIKE PULSES OF ANOTHER POLARITY ARE BEING SENSED.