650+ Computer Architecture Solved MCQs


The               format is usually used to store data.

A. bcd
B. decimal
C. hexadecimal
D. octal
Answer» A. bcd
Explanation: the data usually used by computers have to be stored and represented in a particular format for ease of use.

The 8-bit encoding format used to store data in a computer is               

A. ascii
B. ebcdic
C. anci
D. uscii
Answer» B. ebcdic
Explanation: the data to be stored in the computers have to be encoded in a particular way so as to provide secure processing of the data.

A source program is usually in

A. assembly language
B. machine level language
C. high-level language
D. natural language
Answer» C. high-level language
Explanation: the program written and before being compiled or assembled is called as a source program.

Which memory device is generally made of semiconductors?

A. ram
B. hard-disk
C. floppy disk
D. cd disk
Answer» A. ram
Explanation: memory devices are usually made of semiconductors for faster manipulation of the contents.

The small extremely fast, RAM’s are called as                 

A. cache
B. heaps
C. accumulators
D. stacks
Answer» A. cache
Explanation: these small and fast memory devices are compared to ram because they optimize the performance of the system and they only keep files which are required by the current process in them

The ALU makes use of                 to store the intermediate results.

A. accumulators
B. registers
C. heap
D. stack
Answer» A. accumulators
Explanation: the alu is the computational center of the cpu. it performs all mathematical and logical operations. in order to perform better, it uses some internal memory spaces to store immediate results.

The control unit controls other units by generating                         

A. control signals
B. timing signals
C. transfer signals
D. command signals
Answer» B. timing signals
Explanation: this unit is used to control and coordinate between the various parts and components of the cpu.

              are numbers and encoded characters, generally used as operands.

A. input
B. data
C. information
D. stored values
Answer» B. data
Explanation: none.

The Input devices can send information to the processor.

A. when the sin status flag is set
B. when the data arrives regardless of the sin flag
C. neither of the cases
D. either of the cases
Answer» A. when the sin status flag is set
Explanation: the input devices use buffers to store the data received and when the buffer has some data it sends it to the processor.

              bus structure is usually used to connect I/O devices.

A. single bus
B. multiple bus
C. star bus
D. rambus
Answer» A. single bus
Explanation: bus is a bunch of wires which carry address, control signals and data. it is used to connect various components of the computer.

The I/O interface required to connect the I/O device to the bus consists of               

A. address decoder and registers
B. control circuits
C. address decoder, registers and control circuits
D. only control circuits
Answer» C. address decoder, registers and control circuits
Explanation: the i/o devices are connected to the cpu via bus and to interact with the bus they have an interface.

To reduce the memory access time we generally make use of               

A. heaps
B. higher capacity ram’s
C. sdram’s
D. cache’s
Answer» D. cache’s
Explanation: the time required to access a part of the memory for data retrieval.

              is generally used to increase the apparent size of physical memory.

A. secondary memory
B. virtual memory
C. hard-disk
D. disks
Answer» B. virtual memory
Explanation: virtual memory is like an extension to the existing memory.

MFC stands for                         

A. memory format caches
B. memory function complete
C. memory find command
D. mass format command
Answer» B. memory function complete
Explanation: this is a system command enabled when a memory function is completed by a process.

The time delay between two successive initiations of memory operation                 

A. memory access time
B. memory search time
C. memory cycle time
D. instruction delay
Answer» C. memory cycle time
Explanation: the time is taken to finish one task and to start another.

The decoded instruction is stored in

A. ir
B. pc
C. registers
D. mdr
Answer» A. ir
Explanation: the instruction after obtained from the pc, is decoded and operands are fetched and stored in the ir.

Which registers can interact with the secondary storage?

A. mar
B. pc
C. ir
D. r0
Answer» A. mar
Explanation: mar can interact with secondary storage in order to fetch data from it.

During the execution of a program which gets initialized first?

A. mdr
B. ir
C. pc
D. mar
Answer» C. pc
Explanation: for the execution of a process first the instruction is placed in the pc.

Which of the register/s of the processor is/are connected to Memory Bus?

A. pc
B. mar
C. ir
D. both pc and mar
Answer» B. mar
Explanation: mar is connected to the memory bus in order to access the memory.

ISP stands for                     

A. instruction set processor
B. information standard processing
C. interchange standard protocol
D. interrupt service procedure
Answer» A. instruction set processor
Explanation: none.

The internal components of the processor are connected by                 

A. processor intra-connectivity circuitry
B. processor bus
C. memory bus
D. rambus
Answer» B. processor bus
Explanation: the processor bus is used to connect the various parts in order to provide a direct connection to the cpu.

              is used to choose between incrementing the PC or performing ALU operations.

A. conditional codes
B. multiplexer
C. control unit
D. none of the mentioned
Answer» B. multiplexer
Explanation: the multiplexer circuit is used to choose between the two as it can give different results based on the input.

The registers, ALU and the interconnection between them are collectively called as            

A. process route
B. information trail
C. information path
D. data path
Answer» D. data path
Explanation: the operational and

                is used to store data in registers.

A. d flip flop
B. jk flip flop
C. rs flip flop
D. none of the mentioned
Answer» A. d flip flop
Explanation: none.

The main virtue for using single Bus structure is                           

A. fast data transfers
B. cost effective connectivity and speed
C. cost effective connectivity and ease of attaching peripheral devices
D. none of the mentioned
Answer» C. cost effective connectivity and ease of attaching peripheral devices
Explanation: by using a single bus structure we can minimize the amount of hardware (wire) required and thereby reducing the cost.

              are used to overcome the difference in data transfer speeds of various devices.

A. speed enhancing circuitory
B. bridge circuits
C. multiple buses
D. buffer registers
Answer» D. buffer registers
Explanation: by using buffer registers, the processor sends the data to the i/o device at the processor speed and the data gets stored in the buffer. after that the data gets sent to or from the buffer to the devices at the device speed.

To extend the connectivity of the processor bus we use                   

A. pci bus
B. scsi bus
C. controllers
D. multiple bus
Answer» A. pci bus
Explanation: pci bus is used to connect other peripheral devices that require a direct connection with the processor.

IBM developed a bus standard for their line of computers ‘PC AT’ called

A. ib bus
B. m-bus
C. isa
D. none of the mentioned
Answer» C. isa
Explanation: none.

The bus used to connect the monitor to the CPU is               

A. pci bus
B. scsi bus
C. memory bus
D. rambus
Answer» B. scsi bus
Explanation: scsi bus is usually used to connect video devices to the processor.

ANSI stands for

A. american national standards institute
B. american national standard interface
C. american network standard interfacing
D. american network security interrupt
Answer» A. american national standards institute
Explanation: none.

           register Connected to the Processor bus is a single-way transfer capable.

A. pc
B. ir
C. temp
D. z
Answer» D. z
Explanation: the z register is a special register which can interact with the processor bus only.

In multiple Bus organisation, the registers are collectively placed and referred as               

A. set registers
B. register file
C. register block
D. map registers
Answer» B. register file
Explanation: none.

The main advantage of multiple bus organisation over a single bus is            

A. reduction in the number of cycles for execution
B. increase in size of the registers
C. better connectivity
D. none of the mentioned
Answer» A. reduction in the number of cycles for execution
Explanation: none.

The ISA standard Buses are used to connect                         

A. ram and processor
B. gpu and processor
C. harddisk and processor
D. cd/dvd drives and processor
Answer» C. harddisk and processor
Explanation: none.

During the execution of the instructions, a copy of the instructions is placed in the               

A. register
B. ram
C. system heap
D. cache
Answer» D. cache
Explanation: none.

Two processors A and B have clock frequencies of 700 Mhz and 900 Mhz respectively. Suppose A can execute an instruction with an average of 3 steps and B can execute with an average of 5 steps. For the execution of the same instruction which processor is faster?

A. a
B. b
C. both take the same time
D. insufficient information
Answer» A. a
Explanation: the performance of a system can be found out using the basic performance formula.

A processor performing fetch or decoding of different instruction during the execution of another instruction is called               

A. super-scaling
B. pipe-lining
C. parallel computation
D. none of the mentioned
Answer» B. pipe-lining
Explanation: pipe-lining is the process of improving the performance of the system by processing different instructions at the same time, with only one instruction performing one specific operation.

The clock rate of the processor can be improved by                     

A. improving the ic technology of the logic circuits
B. reducing the amount of processing done in one step
C. by using the overclocking method
D. all of the mentioned
Answer» D. all of the mentioned
Explanation: the clock rate(frequency of the processor) is the hardware dependent quantity it is fixed for a given processor.

An optimizing Compiler does

A. better compilation of the given piece of code
B. takes advantage of the type of processor and reduces its process time
C. does better memory management
D. none of the mentioned
Answer» B. takes advantage of the type of processor and reduces its process time
Explanation: an optimizing compiler is a compiler designed for the specific purpose of increasing the operation speed of the processor by reducing the time taken to compile the program instructions.

SPEC stands for                                  

A. standard performance evaluation code
B. system processing enhancing code
C. system performance evaluation corporation
D. standard processing enhancement corporation
Answer» C. system performance evaluation corporation
Explanation: spec is a corporation that started to standardize the evaluation method of a system’s performance.

As of 2000, the reference system to find the performance of a system is

A. ultra sparc 10
B. sun sparc
C. sun ii
D. none of the mentioned
Answer» A. ultra sparc 10
Explanation: in spec system of measuring a system’s performance, a system is used as a reference against which other systems are compared and performance is determined.

If a processor clock is rated as 1250 million cycles per second, then its clock period is                   

A. 1.9 * 10-10 sec
B. 1.6 * 10-9 sec
C. 1.25 * 10-10 sec
D. 8 * 10-10 sec
Answer» D. 8 * 10-10 sec
Explanation: none.

If the instruction, Add R1, R2, R3 is executed in a system that is pipe-lined, then the value of S is (Where S is a term of the Basic performance equation)?

A. 3
B. ~2
C. ~1
D. 6
Answer» C. ~1
Explanation: s is the number of steps

CISC stands for

A. complete instruction sequential compilation
B. computer integrated sequential compiler
C. complex instruction set computer
D. complex instruction sequential compilation
Answer» C. complex instruction set computer
Explanation: cisc is a type of system architecture where complex instructions

In the case of, Zero-address instruction method the operands are stored in            

A. registers
B. accumulators
C. push down stack
D. cache
Answer» C. push down stack
Explanation: in this case, the operands are implicitly loaded onto the alu.

As of 2000, the reference system to find the SPEC rating are built with             Processor.

A. intel atom sparc 300mhz
B. ultra sparc -iii 300mhz
C. amd neutrino series
D. asus a series 450 mhz
Answer» B. ultra sparc -iii 300mhz
Explanation: none.

The instruction, Add #45,R1 does

A. adds the value of 45 to the address of r1 and stores 45 in that address
B. adds 45 to the value of r1 and stores it in r1
C. finds the memory location 45 and adds that content to that of r1
D. none of the mentioned
Answer» B. adds 45 to the value of r1 and stores it in r1
Explanation: the instruction is using immediate addressing mode hence the value is stored in the location 45 is added.

The addressing mode which makes use of in-direction pointers is               

A. indirect addressing mode
B. index addressing mode
C. relative addressing mode
D. offset addressing mode
Answer» A. indirect addressing mode
Explanation: in this addressing mode, the value of the register serves as another memory location and hence we use pointers to get the data.

In the following indexed addressing mode instruction, MOV 5(R1), LOC the effective address is               

A. ea = 5+r1
B. ea = r1
C. ea = [r1]
D. ea = 5+[r1]
Answer» D. ea = 5+[r1]
Explanation: this instruction is in base with offset addressing mode.

The addressing mode/s, which uses the PC instead of a general purpose register is               

A. indexed with offset
B. relative
C. direct
D. both indexed with offset and direct
Answer» B. relative
Explanation: in this, the contents of the pc are directly incremented.

The addressing mode, where you directly specify the operand value is

A. immediate
B. direct
C. definite
D. relative
Answer» A. immediate
Explanation: none.

           addressing mode is most suitable to change the normal sequence of execution of instructions.

A. relative
B. indirect
C. index with offset
D. immediate
Answer» A. relative
Explanation: the relative addressing mode is used for this since it directly updates the pc.

Which method/s of representation of numbers occupies a large amount of memory than others?

A. sign-magnitude
B. 1’s complement
C. 2’s complement
D. 1’s & 2’s compliment
Answer» A. sign-magnitude
Explanation: it takes more memory as one bit used up to store the sign.

Which method of representation has two representations for ‘0’?

A. sign-magnitude
B. 1’s complement
C. 2’s complement
D. none of the mentioned
Answer» A. sign-magnitude
Explanation: one is positive and one for negative.

When we perform subtraction on -7 and 1 the answer in 2’s complement form is                     

A. 1010
B. 1110
C. 0110
D. 1000
Answer» D. 1000
Explanation: first the 2’s complement is found and that is added to the number and the overflow is ignored.

The processor keeps track of the results of its operations using flags called                   

A. conditional code flags
B. test output flags
C. type flags
D. none of the mentioned
Answer» A. conditional code flags
Explanation: these flags are used to indicate if there is an overflow or carry or zero result occurrence.

The register used to store the flags is called as                     

A. flag register
B. status register
C. test register
D. log register
Answer» B. status register
Explanation: the status register stores the condition codes of the system.

In some pipelined systems, a different instruction is used to add to numbers which can affect the flags upon

A. and gate
B. nand gate
C. nor gate
D. xor gate
Answer» D. xor gate
Explanation: none.

The most efficient method followed by computers to multiply two unsigned numbers is                 

A. booth algorithm
B. bit pair recording of multipliers
C. restoring algorithm
D. non restoring algorithm
Answer» B. bit pair recording of multipliers
Explanation: none.

For the addition of large integers, most of the systems make use of               

A. fast adders
B. full adders
C. carry look-ahead adders
D. none of the mentioned
Answer» C. carry look-ahead adders
Explanation: in this method, the carries for each step are generated first.

In a normal n-bit adder, to find out if an overflow as occurred we make use of

A. counter
B. flip flop
C. shift register
D. push down stack
Answer» C. shift register
Explanation: the shift registers are used to store the multiplied answer.

The smallest entity of memory is called                 

A. cell
B. block
C. instance
D. unit
Answer» A. cell
Explanation: each data is made up of a number of units.

The collection of the above mentioned entities where data is stored is called               

A. block
B. set
C. word
D. byte
Answer» C. word
Explanation: each readable part of the data is called blocks.

If a system is 64 bit machine, then the length of each word will be                 

A. 4 bytes
B. 8 bytes
C. 16 bytes
D. 12 bytes
Answer» B. 8 bytes
Explanation: a 64 bit system means, that at a time 64 bit instruction can be executed.

The type of memory assignment used in Intel processors is            

A. little endian
B. big endian
C. medium endian
D. none of the mentioned
Answer» A. little endian
Explanation: the method of address allocation to data to be stored is called as memory assignment.

When using the Big Endian assignment to store a number, the sign bit of the number is stored in            

A. the higher order byte of the word
B. the lower order byte of the word
C. can’t say
D. none of the mentioned
Answer» A. the higher order byte of the word
Explanation: none.

To get the physical address from the logical address generated by CPU we use

A. mar
B. mmu
C. overlays
D. tlb
Answer» B. mmu
Explanation: memory management unit, is used to add the offset to the logical address generated by the cpu to get the physical address.

           method is used to map logical addresses of variable length onto physical memory.

A. paging
B. overlays
C. segmentation
D. paging with segmentation
Answer» C. segmentation
Explanation: segmentation is a process in which memory is divided into groups of variable length called segments.

During the transfer of data between the processor and memory we use

A. cache
B. tlb
C. buffers
D. registers
Answer» D. registers
Explanation: none.

Physical memory is divided into sets of finite size called as               

A. frames
B. pages
C. blocks
D. vectors
Answer» A. frames
Explanation: none.

Add #%01011101,R1 , when this instruction is executed then                     

A. the binary addition between the operands takes place
B. the numerical value represented by the binary value is added to the value of r1
C. the addition doesn’t take place, whereas this is similar to a mov instruction
D. none of the mentioned
Answer» A. the binary addition between the operands takes place
Explanation: this performs operations in binary mode directly.

If we want to perform memory or arithmetic operations on data in Hexa- decimal mode then we use                      symbol before the operand.

A. ~
B. !
C. $
D. *
Answer» C. $
Explanation: none.

When generating physical addresses from a logical address the offset is stored in                       

A. translation look-aside buffer
B. relocation register
C. page table
D. shift register
Answer» B. relocation register
Explanation: in the mmu the relocation register stores the offset address.

The technique used to store programs larger than the memory is                           

A. overlays
B. extension registers
C. buffers
D. both extension registers and buffers
Answer» A. overlays
Explanation: in this, only a part of the program getting executed is stored on the memory and later swapped in for the other part.

The unit which acts as an intermediate agent between memory and backing store to reduce process time is                         

A. tlb’s
B. registers
C. page tables
D. cache
Answer» D. cache
Explanation: the cache’s help in data transfers by storing most recently used memory pages.

Does the Load instruction do the following operation/s?

A. loads the contents of a disc onto a memory location
B. loads the contents of a location onto the accumulators
C. load the contents of the pcb onto the register
D. none of the mentioned
Answer» B. loads the contents of a location onto the accumulators
Explanation: the load instruction is basically used to load the contents of a memory location onto a register.

Complete the following analogy:- Registers are to RAM’s as Cache’s are to

A. system stacks
B. overlays
C. page table
D. tlb
Answer» D. tlb
Explanation: none.

The BOOT sector files of the system are stored in                         

A. harddisk
B. rom
C. ram
D. fast solid state chips in the motherboard
Answer» B. rom
Explanation: the files which are required for the starting up of a system are stored on the rom.

The transfer of large chunks of data with the involvement of the processor is done by                 

A. dma controller
B. arbitrator
C. user system programs
D. none of the mentioned
Answer» A. dma controller
Explanation: this mode of transfer involves the transfer of a large block of data from the memory.

Which of the following techniques used to effectively utilize main memory?

A. address binding
B. dynamic linking
C. dynamic loading
D. both dynamic linking and loading
Answer» C. dynamic loading
Explanation: in this method only when the routine is required is loaded and hence saves memory.

RTN stands for                         

A. register transfer notation
B. register transmission notation
C. regular transmission notation
D. regular transfer notation
Answer» A. register transfer notation
Explanation: this is the way of writing the assembly language code with the help of register notations.

The instruction, Add Loc,R1 in RTN is

A. addsetcc loc+r1
B. r1=loc+r1
C. not possible to write in rtn
D. r1<-[loc]+[r1]
Answer» D. r1<-[loc]+[r1]
Explanation: none.

Can you perform an addition on three operands simultaneously in ALN using Add instruction?

A. yes
B. not possible using add, we’ve to use addsetcc
C. not permitted
D. none of the mentioned
Answer» C. not permitted
Explanation: you cannot perform an addition on three operands simultaneously because the third operand is where the result is stored.

The instruction, Add R1,R2,R3 in RTN is                 

A. r3=r1+r2+r3
B. r3<-[r1]+[r2]+[r3]
C. r3=[r1]+[r2]
D. r3<-[r1]+[r2]
Answer» D. r3<-[r1]+[r2]
Explanation: in rtn the first operand is the destination and the second operand is the source.

In a system, which has 32 registers the register id is                       long.

A. 16 bit
B. 8 bits
C. 5 bits
D. 6 bits
Answer» C. 5 bits
Explanation: the id is the name tag given to each of the registers and used to identify them.

While using the iterative construct (Branching) in execution                              instruction is used to check the condition.

A. testandset
B. branch
C. testcondn
D. none of the mentioned
Answer» B. branch
Explanation: branch instruction is used to check the test condition and to perform the memory jump with the help of offset.

The condition flag Z is set to 1 to indicate                 

A. the operation has resulted in an error
B. the operation requires an interrupt call
C. the result is zero
D. there is no empty register available
Answer» C. the result is zero
Explanation: this condition flag is used

                      converts the programs written in assembly language into machine instructions.

A. machine compiler
B. interpreter
C. assembler
D. converter
Answer» C. assembler
Explanation: an assembler is a software used to convert the programs into machine instructions.

The instructions like MOV or ADD are called as               

A. op-code
B. operators
C. commands
D. none of the mentioned
Answer» A. op-code
Explanation: this op – codes tell the

The assembler directive EQU, when used in the instruction: Sum EQU 200 does                   

A. finds the first occurrence of sum and assigns value 200 to it
B. replaces every occurrence of sum with 200
C. re-assigns the address of sum by adding 200 to its original address
D. assigns 200 bytes of memory starting the location of sum
Answer» B. replaces every occurrence of sum with 200
Explanation: this basically is used to replace the variable with a constant value.

The directive used to perform initialization before the execution of the code is               

A. reserve
B. store
C. dataword
D. equ
Answer» C. dataword
Explanation: none.

           directive is used to specify and assign the memory required for the block of code.

A. allocate
B. assign
C. set
D. reserve
Answer» D. reserve
Explanation: this instruction is used to allocate a block of memory and to store the object code of the program there.

           directive specifies the end of execution of a program.

A. end
B. return
C. stop
D. terminate
Answer» B. return
Explanation: this instruction directive is used to terminate the program execution.

The last statement of the source program should be                 

A. stop
B. return
C. op
D. end
Answer» D. end
Explanation: this enables the processor to load some other process.

The assembler stores all the names and their corresponding values in               

A. special purpose register
B. symbol table
C. value map set
D. none of the mentioned
Answer» B. symbol table
Explanation: the table where the assembler stores the variable names along with their corresponding memory locations and values.

The assembler stores the object code in               

A. main memory
B. cache
C. ram
D. magnetic disk
Answer» D. magnetic disk
Explanation: after compiling the object code, the assembler stores it in the magnetic disk and waits for further execution.

The utility program used to bring the object code into memory for execution is               

A. loader
B. fetcher
C. extractor
D. linker
Answer» A. loader
Explanation: the program is used to load the program into memory.

To overcome the problems of the assembler in dealing with branching code we use            

A. interpreter
B. debugger
C. op-assembler
D. two-pass assembler
Answer» D. two-pass assembler
Explanation: this creates entries into the symbol table first and then creates the object code.

The return address of the Sub-routine is pointed to by                 

A. ir
B. pc
C. mar
D. special memory registers
Answer» B. pc
Explanation: the return address from the subroutine is pointed to by the pc.

The location to return to, from the subroutine is stored in                 

A. tlb
B. pc
C. mar
D. link registers
Answer» D. link registers
Explanation: the registers store the return address of the routine and is pointed to by the pc.
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