Shift Registers MCQs

Question 1

If an 8-bit ring counter has an initial state 10111110, what is the state after the fourth clock pulse?

Accepted Answer

11101011

Answer

00010111

Answer

11110000

Answer

00000000

Question 2

A 4-bit shift register that receives 4 bits of parallel data will shift to the ________ by ________ position(s) for each clock pulse.

Accepted Answer

right, one

Answer

right, two

Answer

left, one

Answer

left, three

Question 3

How many clock pulses will be required to completely load serially a 5-bit shift register?

Accepted Answer

5

Answer

2

Answer

3

Answer

4

Question 4

How is a strobe signal used when serially loading a shift register?

Accepted Answer

to control the number of clocks

Answer

to turn the register on and off

Answer

to determine which output Qs are used

Answer

to determine the FFs that will be used

Question 5

An 8-bit serial in/serial out shift register is used with a clock frequency of 150 kHz. What is the time delay between the serial input and the Q3 output?

Accepted Answer

26.67 s

Answer

1.67 s

Answer

26.7 ms

Answer

267 ms

Question 6

What are the three output conditions of a three-state buffer?

Accepted Answer

both of the above

Answer

HIGH, LOW, float

Answer

1, 0, float

Answer

neither of the above

Question 7

The primary purpose of a three-state buffer is usually:

Accepted Answer

to provide isolation between the input device and the data bus

Answer

to provide the sink or source current required by any device connected to its output without loading down the output device

Answer

temporary data storage

Answer

to control data flow

Question 8

What is the difference between a ring shift counter and a Johnson shift counter?

Accepted Answer

The feedback is reversed.

Answer

There is no difference.

Answer

A ring is faster.

Answer

The Johnson is faster.

Question 9

When is it important to use a three-state buffer?

Accepted Answer

when two or more outputs are connected to the same input

Answer

when all outputs are normally HIGH

Answer

when all outputs are normally LOW

Answer

when two or more outputs are connected to two or more inputs