Logic Gates » Exercise – 2

51. Which type of gate can be used to add two bits?

(a) Ex-OR

(b) Ex-NOR

(c) Ex-NAND

(d) NOR

52. Show from the truth table how an exclusive-OR gate can be used to invert the data on one input if the other input is a special control function.

(a) Using A as the control, when A = 0, X is the same as B. When A = 1, X is the same as B.

(b) Using A as the control, when A = 0, X is the same as B. When A = 1, X is the inverse of B.

(c) Using A as the control, when A = 0, X is the inverse of B. When A = 1, X is the same as B.

(d) Using A as the control, when A = 0, X is the inverse of B. When A = 1, X is the inverse of B.

53. Parity systems are defined as either________ or ________ and will add an extra ________ to the digital information being transmitted.

(a) positive, negative, byte

(b) odd, even, bit

(c) upper, lower, digit

(d) on, off, decimal

54. The Ex-NOR is sometimes called the ________.

(a) parity gate

(b) equality gate

(c) inverted OR

(d) parity gate or the equality gate

55. If a 3-input NOR gate has eight input possibilities, how many of those possibilities will result in a HIGH output?

(a) 1

(b) 2

(c) 7

(d) 8

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