Question

If a NOR gate is used for the terminal count to detect when the counter value is 0 in a decrementer, and the terminal count of the down-counter is 1 when the count is 0, the terminal count is:

A) Always 0
B) Always 1
C) Variable based on the counter's state
D) Not determined by the gate used

Answer 1

The terminal count of a NOR gate used in a down-counter is always 1 when the counter value is 0, because a NOR gate only outputs a high signal when all of its inputs are low.

Step-by-step explanation:

If a NOR gate is used for the terminal count to detect when the counter value is 0 in a decrementer, and the terminal count of the down-counter is 1 when the count is 0, it suggests that the NOR gate is configured in such a way that it outputs a 1 when all its inputs are 0. In a digital circuit, a down-counter subtracts from the count value, and the counter reaches a value of 0 after completing the countdown. Since the NOR gate produces a high output only when all inputs are low, and in this case, a high output (1) indicates that the count has reached 0, the terminal count is given as 1 when the count is indeed 0. Therefore, the terminal count in this situation is Always 1 when the counter value is 0.