Digital Electronics-Shift Registers
Digital Electronics-Shift Registers
11. A modulus-12 ring counter requires a minimum of ________.
- 10 flip-flops
- 12 flip-flops
- 6 flip-flops
- 2 flip-flops
12. Stepper motors have become popular in digital automation systems because ________.
- of their low cost
- they are driven by sequential digital signals
- they can be used to provide repetitive mechanical movement
- they are driven by sequential digital signals and can be used to provide repetitive mechanical movement
13. The group of bits 11001 is serially shifted (right-most bit first) into a 5-bit parallel output shift register with an initial state 01110. After three clock pulses, the register contains ________.
- 01110
- 00001
- 00101
- 00110
14. Assume that a 4-bit serial in/serial out shift register is initially clear. We wish to store the nibble 1100. What will be the 4-bit pattern after the second clock pulse? (Right-most bit first.)
- 1100
- 0011
- 0000
- 1111
15. A serial in/parallel out, 4-bit shift register initially contains all 1s. The data nibble 0111 is waiting to enter. After four clock pulses, the register contains ________.
- 0000
- 1111
- 0111
- 1000
16. With a 200 kHz clock frequency, eight bits can be serially entered into a shift register in ________.
- 4 µs
- 40 µs
- 400 µs
- 40 ms
17. An 8-bit serial in/serial out shift register is used with a clock frequency of 2 MHz to achieve a time delay (td) of ________.
- 16 s
- 8 s
- 4 s
- 2 s
18. A sequence of equally spaced timing pulses may be easily generated by which type of counter circuit?
- ring shift
- clock
- Johnson
- binary
19. The bit sequence 10011100 is serially entered (right-most bit first) into an 8-bit parallel out shift register that is initially clear. What are the Q outputs after four clock pulses?
- 10011100
- 11000000
- 00001100
- 11110000
20. If an 8-bit ring counter has an initial state 10111110, what is the state after the fourth clock pulse?
- 11101011
- 00010111
- 11110000
- 00000000