B CompE Bachelor of Computer Engineering Digital Logic and Circuit Design 2

Question 1

What is the hexadecimal representation of the binary number 11110000?

Accepted Answer

F0

Answer

Splitting 11110000 into two nibbles: 1111 = 0xF and 0000 = 0x0, so the result is 0xF0.

Question 2

What is the purpose of a multiplexer (MUX) in digital circuits?

Accepted Answer

Select one of many input signals and forward it to a single output

Answer

A multiplexer selects one of several input lines based on select signals and routes it to a single output line.

Question 3

Which Boolean theorem states that A + A = A and A AND A = A?

Accepted Answer

Idempotent Law

Answer

The Idempotent Law states that ORing or ANDing a variable with itself returns the same variable: A+A=A and A.A=A.

Question 4

In a full adder, how many inputs does it take?

Accepted Answer

3

Answer

A full adder takes three inputs: two significant bits (A and B) and a carry-in (Cin), producing a sum and carry-out.

Question 5

Which type of counter uses a sequence where only one bit changes between consecutive states?

Accepted Answer

Gray code counter

Answer

A Gray code counter uses the Gray code sequence where only one bit changes between consecutive values, minimizing switching errors.

B CompE Bachelor of Computer Engineering Practice Test