Digital Electronics-Shift Registers
Digital Electronics-Shift Registers
21. How would a latch circuit be used in a microprocessor system?
- as transportation for Intel employees
- for a group of data that is the same
- as a set of common connections for transfer of data
22. A 4-bit shift register that receives 4 bits of parallel data will shift to the ________ by ________ position(s) for each clock pulse.
- right, one
- right, two
- left, one
- left, three
23. How many clock pulses will be required to completely load serially a 5-bit shift register?
- 2
- 3
- 4
- 5
24. How is a strobe signal used when serially loading a shift register?
- to turn the register on and off
- to control the number of clocks
- to determine which output Qs are used
- to determine the FFs that will be used
25. What are the three output conditions of a three-state buffer?
- HIGH, LOW, float
- 1, 0, float
- both of the above
- neither of the above
26. The primary purpose of a three-state buffer is usually:
- to provide isolation between the input device and the data bus
- to provide the sink or source current required by any device connected to its output without loading down the output device
- temporary data storage
- to control data flow
27. What is the difference between a ring shift counter and a Johnson shift counter?
- There is no difference.
- A ring is faster.
- The feedback is reversed.
- The Johnson is faster.
28. What is a recirculating register?
- serial out connected to serial in
- all Q outputs connected together
- a register that can be used over again
29. When is it important to use a three-state buffer?
- when two or more outputs are connected to the same input
- when all outputs are normally HIGH
- when all outputs are normally LOW
- when two or more outputs are connected to two or more inputs
30. A bidirectional 4-bit shift register is storing the nibble 1110. Its input is LOW. The nibble 0111 is waiting to be entered on the serial data-input line. After two clock pulses, the shift register is storing ________.
- 1110
- 0111
- 1000
- 1001