The accumulated value in an up-counter instruction is currently 7. What will be the accumulator value after the following series of pulses is applied to the input of the counter?
(Points : 2)a. 12
b. 17
c. 9
d.10

The correct answer is C, which is 9

Explanation:

UP COUNTER

Since the accumulated value is 7, when it increments by two pulses the value of the accumulator increase to 9.

Up counter counts a value from the current value when a signal arrives at the input terminal. There is a reset terminal and preset value too. The counter counts up until the count reaches the preset value and resets. Whenever the input value changes from 0 to 1 the counter increment 1 from the preset value.

The up-counter is an output instruction whose function is to increment its accumulated value on false-to-true transitions of its instruction. It thus can be used to count false-to-true transitions of an input instruction and then trigger an event after a required number of counts or transitions. The up-counter output instruction will increment by 1 each time the counted event occurs.