Shift Register Question & AnswersMay 17, 2022 By WatElectronics This article provides 100 multiple choice questions and answers on shift registers for engineering students. These MCQs are available with a hint and appropriate link where the user can get information on relevant topics. The following shift register MCQs are very helpful for beginners, students, and professionals for preparing the exams, quizzes, and interviews by knowing the basics of the shift register concept.The set of flip-flops (FFs) which are used to store the binary data is called a register. A shift register is a digital circuit including a group of flip-flops where one flip flop output is connected to the next flip flop input. They share a single CLK signal to store the data within the system to move from one place to other. There are five types of shift registers shift right, shift left, circular, bidirectional, and linear feedback. In shift registers, there are four modes of operation serial in serial out (SISO), serial in parallel out (SIPO), parallel in parallel out (PIPO) and parallel in serial out (PISO) shift registers.The advantages of shift registers include; shift registers are very fast to use, simple design, data conversion is faster, used to encrypt/decrypt the data, track the data, etc. The main disadvantage of the shift register is; that the output current produced by this register is limited. The applications of shift registers mainly include; these registers are used to store the data temporarily, transfer the data, used in calculators, computers, etc. By using these registers, adding binary inputs to the microprocessor as it includes a fixed number of input and output pins.1). Which of the following mode is used as control inputs to a 4-bit universal shift register? Loopback mode Parallel load mode Serial input mode All of the above HintIt stores the data in parallel.2). The number of flip-flops in a shift register is dependent upon? The modulus of the counter The number of stages in the counter The number of digits to be stored None of the above HintIt depends on the state at the FF.3). In which mode can we provide data to all the flip-flops simultaneously? Loopback mode Serial input mode Parallel input mode All of the above HintIn this mode, data communication can be done in between devices4). A shift register is a digital circuit that _____________ . Stores data. Shifts the data from left to right. Shifts the data from right to left. all of the above. HintData can move left ,right and stored.5). What is a shift register? An adder circuit A memory circuit A combinational circuit A decoder circuit HintThese circuits are used in computer, calculators, etc.6). What type of register is a shift register? Digital Analog Both 1 and 2 Neither 1 nor 2 HintShift register is a digital circuit build with Flip Flops.7). A shift register is made up of how many flip-flops? One Two Three or more None of the above HintIt uses minimum three flip flops and above.8). What happens when a shift register is clocked? Stays the same (no change) Changes to the next bit in sequence (shifts) Changes to an opposite state (complements) None of the above HintThe transmission of data can be done from one location to other.9). A shift register can have __________ data input and __________ data output lines. Only one, only one Two, two One, two Three, two HintShift register can have single input and two outputs.10). A shift register can be used as a ___________-bit register by connecting all the parallel outputs together and applying the same input to all the parallel inputs. 4-bit 8-bit 16-bit n-bit HintIt can be used as number of bit register.11). Which among the following is the main advantage of using a shift register? Ease of use and cost effective solution for applications that require several I/O pins at a time. It is used where single input and single output is used. Ease of use and cost effective solution for applications that require less number of I/O pins at a time. None of these. HintThese are applicable where number of I/O pins are used.12). Which of the following type of shift register is used in 8085 microprocessor? Serial Parallel Both a and b None of the mentioned HintA SIPO shift register is used in 8085 microprocessor.13). Which of the following is true about shift registers? It is not used to store multi-bit data. They are available only in the parallel mode of operation. They are useful for data transfer from one location to another. All of the above. HintThese registers uses clk signals to transmit the data.14). Which of the following is not a characteristic of universal shift registers? Serial in/serial out (SISO) operation is possible. SISO operation is not possible. Serial in/parallel out (SIPO) operation is possible. Parallel in/serial out (PISO) operation is possible. HintThe operation of serial input serial output is not possible.15). Which of the following shift registers can be used as both PISO and SIPO? 4-bit parallel-in serial-out shift register. 4-bit universal shift register. 4-bit serial-in/serial-out shift register. 4-bit parallel load serial in, serial out shift. HintThe USR is used as SIPO & PISO.16). What is the difference between a SISO, SIPO and PISO shift register? A SISO has one data input, while a SIPO has 2 . A SIPO has one data input, while a PISO has 2. A PISO has one data input, while a SISO has 2. A PISO has two data inputs, while a SIPO has 1. None of the above answers are correct. HintThe common difference between these shift registers is data transmission.17). What is one of the main functions of a shift register? To convert digital information into analog signals. To control voltage levels according to clock pulses. To store bits and bytes of binary data temporarily. To convert serial digital information into parallel or parallel to serial. HintIt is used to convert the digital data.18). Which of the following shift registers are also called universal shift registers? n-bit right shifter with parallel load. n-bit right shifter with parallel load & clear and. n-bit right shifter and left shift register with parallel load. All of above. HintThese registers have the capabilities of right shift and left shift.19). A ________ is a group of special circuit with their outputs connected in series to form a register. Data register Shift register Control register Accumulator HintIt is a digital circuit which includes a set of flip flops.20). What are the two basic types of shift registers? Latched & unlatched registers. 4-bit & 8-bit registers. SISO & PIPO SINO & PINO HintThese are serial input & output and Parallel input and output.21). A shift register is essentially a group of flip-flops, so what can they be used for? They can be used to store data. They can be used to count sequences. They can be used to shift the numbers. They can be used to multiply numbers together. All the above. HintThese registers are used for multiple purposes.22). Which of the following statements about shift registers is true? Parallel-in and serial-out shift registers are used when we want to store large amounts of data in a small space. Serial-in and serial-out shift registers are used when we want to store large amounts of data in a small space. Parallel-in and parallel-out shift registers are used when we want to transmit data over long distances. Parallel-in and serial-out shift registers are used when we want to transmit data over long distances. HintThese registers are also know as PISO.23). Why would you use a shift register? To connect multiple devices together so the output can be fed back into the input. To connect multiple devices together but not have the output fed back into the input. To connect multiple devices together and feed back the output into the first device. To connect multiple devices together and feed back the output into any device except for the first device. HintThe one FF output is connected to next FF input.24). What types of functions can a shift register perform? As data storage spaces Data movement devices Temporary storage units All of the above HintIt performs different operations like data transfer, storage, etc.25). What is the difference between a serial and parallel shift register? A serial shift register shifts in data serially, while a parallel shift register shifts in data in parallel. A serial shift register shifts out data serially, while a parallel shift register shifts out data in parallel. A serial shift register shifts out data serially, while a parallel shift register shifts out data serially as well. A serial shift register shifts out data in parallel, while a parallel shift register shifts out data in parallel as well. HintThe difference between these two registers is mainly data transmission.Shift Register MCQs for Exams26). Which of the following is correct about serial in/serial out shift register? 1 input, 1 output 1 input, 2 outputs 2 inputs, 1 output 2 inputs, 2 outputs HintIt includes one input and one output.27). Which type of shift register is used to implement a digital up-down counter? Serial in/serial out (SISO) type Serial in/parallel out (SIPO) type Parallel in/serial out (PISO) type Parallel in/parallel out (PIPO) type HintIn this type of register, data loading occurs within serial-mode.28). Shift register is a___? Digital Circuit Analog Circuit Logic circuit Series circuit HintThese circuits uses set of Flip Flops.29). How many stages are in a 74LS170 parallel-out, serial-in shift register? 8 16 4 2 HintIt is organized 4 four words through four bits.30). Which of the following is a serial-in, parallel-out shift register? 74LS164 74LS165 74LS168 74LS169 HintIt is a high speed 8-bit register.31). Which of the following is a disadvantage of shift registers? The memory size of a shift register is limited to the number of flip-flops used in the register. The time required to access data from a shift register is more than that of a random access memory unit. The reliability of the circuit decreases as its complexity increases. None of above. 32). Which of the following is a advantage of shift registers? The memory size of a shift register is limited to the number of flip-flops used in the register. The time required to access data from a shift register is less than that of a random access memory unit. The reliability of the circuit decreases as its complexity increases. None of above HintThe time taken to access the data is high as compared to RAM unit.33). The maximum clock frequency of the 74HC595 shift register is? 50MHz 100MHz 120MHz 40MHz HintIt ranges from 60 to 110 MHz.34). A shift register with a feedback function is useful in _______applications? Multiplication Division Ones Compliment Twos Complement A&B HintIt is used to make arithmetic operations.35). Which of the following statements are TRUE regarding shift registers? A shift register is a group of flip flops. It is not used for data storage. It is not used for the data movement. Shift register includes set of latches. HintIn this digital circuit, the output of one FF is connected to next FF.36). What is serial in parallel out (SIPO) shift register? Data is serial loaded into parallel output attached flip-flops. Data is loaded into a single flip-flop and output appears parallel. Data is loaded into serial output attached flip-flops and appear in serial order. The data transmission can be done paralelly. HintIt is similar to SISO shift register.37). Which of these is not true about shift registers? They share a single CLK signal, which causes the data stored in the system to shift from one location to the next. By connecting the last flip-flop back to the first, the data can cycle within shifters for extended periods. They use a cascade of flip-flops. The output of one flip-flop is connected to the input of another. HintThey moves the data from one location to other.38). Which of the following terms describes a shift register’s ability to cycle its data within itself, thus acting as memory? Cascading Connecting Cycling Cascoding Hint: By using this the first stage output is connected to next stage input.39). Which of the following is a reason SIPO registers might be attached to the output of microprocessors? When more I/O pins are required than are available. When we need an easier way to convert binary inputs into parallel outputs. When we need more binary inputs than are available, and we don’t want to use serial data. When we need more binary inputs or outputs than are available, but we don’t have enough space on our board for extra pins. HintOnce more general purpose input & output pins are necessary as compared to available ones.40). What is a SIPO register? A type of microprocessor. A serial input-parallel output shift register. A type of storage device that holds data in registers. None of the above HintIt is similar to serial input serial output register.41). Shift registers can also be used as: Extenders Pulse extenders Both a and b Neither a nor b HintThey have longer outputs as compared to the input pulses.42). Does a parallel-in serial-out (PISO) shift register configuration have the data input on lines D1 through D4 in parallel format, D1 being the ....bit? LSB MSB Data bit Binary digit HintIt is a highest digit bit.43). To write the data to the register, what must the Write/Shift control line be held? HIGH LOW EITHER NEITHER HintThe control line should be held not high.44). What are the advantages of using a SIPO shift register? Serial input, parallel output Parallel input, serial output Serial input, serial output Parallel input, parallel output HintIt uses serial input and generates parallel output.45). Which of the following are true about a SIPO Shift Register? It uses edge triggered flip flops. The data is loaded into an internal buffer register first, then copied to an output register when a load signal is received. All flip flops operate at the same frequency. All of the above. HintIt performs all the operations.46). In a Serial Input Serial Output, how is data is shifted? In SISO, a single bit is shifted at a time in either right or left direction under clock control. In SISO, all bits are shifted at the same time in either right or left direction under clock control. In SISO, the entire data is shifted at once in the same direction under clock control. None of the above. HintOne bit can be shifted in any direction under CLK signal.47). What is the first step in designing a serial-in/serial-out shift register? Set all flip-flops to reset. Apply the LSB of the binary number to D3 bit. Pass D3 output to D2 input. Apply binary number 1111. HintIf we reset the flip flops, the errors will be cleared,48). What is the difference between a series input (SI) and a parallel input (PI)? Series input (SI) loads the data one bit at a time while parallel input (PI) loads the data simultaneously. Series input (SI) removes the data one bit at a time while parallel input (PI) removes the data all at the same time. Series input (SI) shifts the contents of the register one bit position to either the left or the right while parallel input (PI) shifts the contents of the register two bit positions to either the left or the right. Series input (SI) and parallel input (PI) are the same. HintThe main difference is the data loading.49). How the data is stored in a SISO shift register? In a parallel form. In a serial form. In a combination of serial and parallel forms. None of the above HintThe data comes in in succession.50). Which of the following digital circuit can store a bit of data and shift it left or right? Encoder ADC Multiplexer Shift register HintThese are used for data movement.Shift Register MCQs for Interviews51). Which of the following is used to create a circular buffer? Encoder ADC Multiplexer Shift register HintThese circuits share single clock signal.52). Which of the following digital circuit is used to make a shift clock?. Encoder ADC Shift register Decoder HintThis circuit uses cascade of flip flops.53). The most common type of shift register is?. SIPO SISO PISO PIPO HintIt uses serial input and generates parallel output.54). A shift counter can be created by using______? Microcontroller ADC Shift register DAC HintIt is one type of digital circuit.55). A shift register chain can be created by using______ . Memory data register Microprocessor Shift register Flip Flop HintIt is used in data processing systems.56). Which of the following is used to create a shift register ladder? Shift register Memory data register Memory address register Processor registers HintIt is a type of digital circuit which uses flip flops.57). A shift register is a______ . Digital circuit that delays a digital input signal. Sequential logic circuit that delays a digital input signal. Digital circuit that delays an analog input signal. Sequential logic circuit that delays an analog input signal. 58). A shift register can be used to _____ . Create a delay in a digital signal. Create a delay in an analog signal. Create a digital-to-analog converter. Create an analog-to-digital converter. 59). The most common type of shift register is the__________ . Serial shift register Parallel shift register Serial-in, parallel-out shift register Parallel-in, serial-out shift register HintIt is also known as SIPO register.60). In a shift register, the output of each stage is the ? Input to the next stage. Input to the previous stage. Output of the previous stage. Output of the next stage. HintIt is used as a feedback.61). A shift register can be used to? Create a delay in a digital signal. Create a delay in an analog signal. Create a digital-to-analog converter. Create an analog-to-digital converter. HintA shift register creates a delay within a digital signal.62). What is the effect of a left shift operation on a binary number? It multiplies the number by two. It divides the number by two. It has no effect on the number. None of the above. HintIt simply increases the number by two.63). What is the purpose of a bidirectional shift register? To multiply binary numbers by two. To divide binary numbers by two. To shift data left or right as selected by a control line. None of the above. HintThe effect of a left shift operation is to multiply the number by two.64). What is the effect of a right shift operation? It multiplies the number by two. It divides the number by two. It has no effect on the number. None of the above HintThe effect of a right shift operation is to separate the number by two.65). What is a Ring counter? A shift register with the serial outputs connected back to the serial inputs in order to produce particular sequences. A type of counter that exhibits a specified sequence of states. A shift register that is used to generate random numbers. A type of counter that is commonly used in digital circuits. HintOutput is fed to input to form a ring.66). What is a Johnson counter? A shift register with the serial outputs connected back to the serial inputs in order to produce particular sequences. A type of counter that exhibits a specified sequence of states. A shift register that is used to generate random numbers. A type of counter that is commonly used in digital circuits. HintIn this counter, the serial outputs are connected to serial inputs.67). What is a ring counter? A shift register in which the output of the most significant stage is fed back to the input of the least significant stage. A counter in which the output of the most significant stage is fed back to the input of the least significant stage. A counter in which the output of the most significant stage is fed back to the input of the second most significant stage. A counter in which the output of the most significant stage is fed back to the input of the third most significant stage. HintThe output of the MS stage is given as feedback to the LS stage input.68).What is the main advantage of a ring counter over a binary counter? The ring counter is self-decoding. The ring counter is more efficient in terms of state usage. The ring counter is easier to use. The ring counter has more states. HintIt doesn’t require a decoder.69). Johnson counter is an example of which type of sequential circuit: Asynchronous sequential circuit Synchronous sequential circuit Counter None of these HintThe output of this circuit changes simply at some discrete moments of time.70). Which of the following counters is known as 2-bit Johnson Counter? MOD-8 counter MOD-4 counter MOD-2 counter MOD-6 counter HintThis mode uses four clock pulses to obtain from 00 to 11. Please fill in the comment box below. Time is Up! Time's up
