Suppose that we want to use the following timer/counter structure as part of a turnstile machine to detect the number of passengers passing through a gate entrance. We will use a sensor placed on the turnstile machine such that every time a passenger passes through the gate entrance, the sensor will send a pulse to the timer/counter to indicate that a new passenger has passed through the entrance. In order to correctly count the events (number of passengers passing through), indicate the logic value that we should set in the "Ctr" signal in the "Clock Select block in the diagram below. Justify your answer. DATA BUS TOVN (Int. Req.) Clock Select Edge Detector Tn . count clear direction clk TONTO Control Logic (From Prescaler) Ctr bottom top