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MATSEC IM Computing practice questions

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Question 1Computer Systems

A program stores the decimal value 200 in a single 8-bit register using two's complement. What bit pattern is held?

  1. 0110 0100
  2. 1000 0000
  3. 1100 1000 Correct answer.
  4. 1100 0111

Explanation

200 as an unsigned 8-bit pattern is 11001000. In two's complement the leading bit is 1, so the value is interpreted as 200 − 256 = −56, which is the result of storing 200 in a signed byte. The stored bits themselves are unchanged by the interpretation, so 11001000 is what the register holds.

Question 2Computer Systems

Which statement about the role of the control unit during the fetch–decode–execute cycle is accurate?

  1. It converts high-level source code into machine instructions
  2. It permanently stores the program instructions currently being run
  3. It generates the timing and control signals that coordinate the other units Correct answer.
  4. It performs arithmetic on the operands held in the general registers

Explanation

The control unit directs the operation of the processor by issuing control signals in the correct sequence and at the correct time, so that each stage of the instruction cycle happens in order. Arithmetic is done by the ALU, instructions are held in memory and cache, and translation of source code is the job of a compiler or assembler.

Question 3Computer Systems

A magnetic hard disk has an average seek time of 9 ms, a rotational speed of 7200 rpm and a transfer rate of 100 MB/s. Using average latency equal to half a rotation, what is the approximate average access time for a 4 KB block, ignoring controller overhead?

  1. 17.2 ms
  2. 4.2 ms
  3. 9.0 ms
  4. 13.2 ms Correct answer.

Explanation

At 7200 rpm the disk makes 120 revolutions per second, so one revolution takes 8.33 ms and average rotational latency is about 4.17 ms. Transferring 4 KB at 100 MB/s takes roughly 0.04 ms. Adding seek (9 ms), latency (4.17 ms) and transfer gives about 13.2 ms.

Question 4Computer Systems

Which memory type is volatile and is used to hold the program and data currently in use by the processor?

  1. Flash memory
  2. RAM Correct answer.
  3. Magnetic tape
  4. ROM

Explanation

RAM is read/write memory that loses its contents when power is removed, and it holds the instructions and data of running programs. ROM and flash are non-volatile and normally store firmware, while magnetic tape is offline backup storage.

Question 5Computer Systems

A CPU has a 20-bit address bus and a 16-bit data bus. What is the maximum directly addressable memory size?

  1. 2 MiB
  2. 512 KiB
  3. 64 KiB
  4. 1 MiB Correct answer.

Explanation

With 20 address lines the processor can select 2^20 distinct addresses, which is 1 048 576 locations. Each location holds one 16-bit word, but addressable size is normally quoted in bytes, giving 2^20 bytes = 1 MiB. The data bus width affects the word size, not the number of addresses.

Question 6Computer Systems

Which statement best describes the purpose of a cache memory between the CPU and main memory?

  1. It increases the total capacity of main memory available to running programs
  2. It translates virtual addresses into physical addresses during execution
  3. It provides non-volatile storage so that data survives a power failure
  4. It reduces the average time to access instructions and data by keeping recently used blocks close to the CPU Correct answer.

Explanation

A cache holds copies of recently accessed main-memory blocks so that many references are satisfied at a much lower latency than a main-memory access. It exploits locality of reference but does not enlarge the logical memory space, retain data without power, or perform address translation.

Question 7Computer Systems

In a pipelined processor, an instruction stream contains a conditional branch. What is the main performance consequence of such a branch?

  1. The clock frequency must be halved to allow the branch to resolve
  2. The pipeline may need to be flushed, wasting cycles if the branch is mispredicted Correct answer.
  3. All subsequent instructions are executed twice to check the result
  4. The instruction cache is disabled until the branch completes

Explanation

Pipelining overlaps instructions, so the next instructions are fetched before a conditional branch is resolved. If the prediction is wrong the speculative work must be discarded, which is called a pipeline flush or penalty. This costs cycles but does not change the clock rate, disable the cache, or duplicate execution.

Question 8Computer Systems

Which of the following is the principal function of an operating system's scheduler?

  1. Translating source code into object code
  2. Deciding which ready process is allocated the processor next Correct answer.
  3. Managing the electrical power supplied to the motherboard
  4. Storing files in directories on the disk

Explanation

The scheduler is the part of the operating system that chooses, from the processes ready to run, which one receives the CPU and for how long. Compilation is done by language translators, file organisation is the job of the file system, and power delivery is handled by hardware.

Question 9Computer Systems

A system uses fixed-size pages of 4 KiB and 32-bit virtual addresses. How many entries can a single-level page table for one process contain?

  1. 2^20 Correct answer.
  2. 2^10
  3. 2^32
  4. 2^12

Explanation

The page offset must cover 4 KiB, which needs 12 bits. The remaining 32 − 12 = 20 bits form the virtual page number, so the page table needs 2^20 entries, one per virtual page.

Question 10Computer Systems

Which protocol is used by a client to retrieve a web page securely over an encrypted connection?

  1. DHCP
  2. HTTPS Correct answer.
  3. FTP
  4. SMTP

Explanation

HTTPS is HTTP carried over a TLS-encrypted connection, so web page requests and responses are protected against eavesdropping and tampering. SMTP sends mail, FTP transfers files without encryption by default, and DHCP assigns network configuration.

Question 11Computer Systems

A host has the IPv4 address 192.168.10.66 with subnet mask 255.255.255.192. What is the network address of its subnet?

  1. 192.168.10.64 Correct answer.
  2. 192.168.10.0
  3. 192.168.10.65
  4. 192.168.10.128

Explanation

The mask 255.255.255.192 gives a block size of 64 addresses (256 − 192), so the subnets start at .0, .64, .128 and .192. The address .66 falls in the block beginning at .64, which is therefore the network address.

Question 12Computer Systems

Which statement correctly contrasts the TCP and UDP transport protocols?

  1. UDP guarantees ordered delivery, while TCP may lose or reorder segments
  2. TCP operates only on local networks, while UDP is used only on the internet
  3. TCP is connectionless and faster, while UDP sets up a connection before sending
  4. TCP provides reliable, ordered delivery with acknowledgements, while UDP sends datagrams without guarantees Correct answer.

Explanation

TCP establishes a connection, numbers segments, acknowledges received data and retransmits lost segments, so it delivers a reliable ordered byte stream. UDP simply sends datagrams with no connection setup, acknowledgement or retransmission, which suits streaming and DNS queries.

Question 13Computer Systems

Which topology connects every device to a single central switch, so that a failure of one cable affects only that device?

  1. Mesh
  2. Ring
  3. Bus
  4. Star Correct answer.

Explanation

In a star topology each device has its own link to a central hub or switch, so a broken cable isolates just one node. On a bus a single cable fault can disable the whole segment, in a ring a break disrupts the loop, and a full mesh needs a link between every pair of nodes.

Question 14Computer Systems

A company network uses the private range 10.0.0.0/8 internally but must allow staff to reach the internet. Which technique is used at the router to let many internal hosts share one public address?

  1. Spanning tree protocol
  2. Domain name system resolution
  3. Network address translation Correct answer.
  4. Dynamic host configuration protocol

Explanation

NAT rewrites the private source addresses of outgoing packets to a single public address and tracks the mapping so replies can be forwarded back to the correct internal host. DHCP assigns addresses, DNS resolves names, and spanning tree prevents loops in switched networks.

Question 15Computer Systems

Which statement about the function of the stack in a running program is correct?

  1. It stores return addresses and local variables for active procedure calls Correct answer.
  2. It maps virtual addresses to physical frames
  3. It permanently stores the program's global variables for the whole run
  4. It holds the machine code of the program currently executing

Explanation

Each procedure call pushes a stack frame containing the return address, saved registers and local variables, and the frame is removed when the procedure returns. Global variables live in a separate data area, machine code resides in the text area, and address mapping is done by the memory management unit.

Question 16Computer Systems

Which statement describes the main advantage of using a compiler rather than an interpreter for a large program?

  1. The translated machine code can be executed repeatedly without re-translation, so it usually runs faster Correct answer.
  2. It executes each statement as it is read, which simplifies debugging
  3. It allows the program to be edited and rerun immediately without a translation step
  4. It requires no knowledge of the target processor's instruction set

Explanation

A compiler translates the whole source program once into an object or executable file, and that machine code can then be run many times at full speed. An interpreter re-examines and executes source statements each run, which is convenient for development but generally slower.

Question 17Computer Systems

A student writes a loop that should run while x < 10 but accidentally writes while x <= 10. Which type of error has been introduced?

  1. A syntax error
  2. A run-time error
  3. A logic error Correct answer.
  4. A linking error

Explanation

The program is syntactically valid and will run without crashing, but it performs one extra iteration, so the output is wrong. Errors where the program compiles and executes but produces incorrect results are logic errors, unlike syntax errors detected by the translator or run-time errors that stop execution.

Question 18Computer Systems

Which statement about a relational database primary key is correct?

  1. It uniquely identifies each record and cannot contain a null value Correct answer.
  2. It is used to encrypt the records it identifies
  3. It may contain duplicate values as long as the records differ elsewhere
  4. It must always be a single numeric field generated by the system

Explanation

A primary key is a column or set of columns chosen to uniquely identify each row, and by definition it must be unique and not null. It can be a text value such as an email address, and it enforces identity rather than providing encryption.

Question 19Computer Systems

A table of orders stores the customer's name and address in every order record. Which design problem does this cause?

  1. Inability to sort the records by date
  2. Data redundancy leading to update anomalies Correct answer.
  3. Loss of referential integrity between tables
  4. Failure of the primary key to be unique

Explanation

Repeating the customer name and address in every order stores the same fact many times, so an address change must be applied to many rows and inconsistent copies can result. This redundancy is removed by normalisation, placing customer details in a separate table referenced by a foreign key.

Question 20Computer Systems

Which statement correctly describes the difference between a compiler and an assembler?

  1. An assembler executes the program line by line, while a compiler produces object code
  2. An assembler translates high-level code, while a compiler translates assembly mnemonics
  3. An assembler translates mnemonic assembly instructions into machine code, while a compiler translates a high-level language Correct answer.
  4. Both translate high-level code but the assembler produces an executable and the compiler does not

Explanation

Assembly language uses mnemonics that correspond closely to machine instructions, and the assembler converts them into binary opcodes and operands. A compiler works from a high-level language such as Python or Java and typically generates assembly or object code.

Question 21Computer Systems

In a truth table for the Boolean expression A AND (NOT B), what is the result when A = 1 and B = 1?

  1. A
  2. 1
  3. B
  4. 0 Correct answer.

Explanation

NOT B with B = 1 gives 0. The AND of A = 1 with 0 gives 0, because an AND gate outputs 1 only when both inputs are 1.

Question 22Computer Systems

A half adder adds two single bits. Which pair of outputs does it produce?

  1. Sum and borrow
  2. Sum and carry Correct answer.
  3. Difference and borrow
  4. Carry and overflow

Explanation

A half adder produces the sum bit from an XOR of the two inputs and the carry bit from an AND of the two inputs. Difference and borrow are outputs of a subtractor, while overflow is detected in wider arithmetic rather than by a half adder.

Question 23Computer Systems

Which statement about the von Neumann architecture is correct?

  1. Programs are held only in cache and never in main memory
  2. Instructions are stored in a separate memory from the data they operate on
  3. Each instruction is executed by a dedicated hardware circuit that is never reused
  4. Instructions and data share the same memory and are fetched over the same bus Correct answer.

Explanation

In the von Neumann model a single memory holds both program instructions and data, and both are transferred over the same bus, which is why the fetch and data cycles cannot overlap. The Harvard architecture is the one that separates instruction and data memories.

Question 24Computer Systems

A file of 3 000 000 bytes is transmitted over a link of 8 Mbit/s. Approximately how long does the transfer take, ignoring protocol overhead?

  1. 24 seconds
  2. 0.375 seconds
  3. 3 seconds Correct answer.
  4. 8 seconds

Explanation

The file is 3 000 000 × 8 = 24 000 000 bits. Dividing by 8 000 000 bits per second gives 3 seconds. Confusing bits with bytes is the usual source of error in this calculation.

Question 25Computer Systems

Which statement about the purpose of a device driver is correct?

  1. It converts a high-level program into machine code before execution
  2. It assigns IP addresses to hosts on a local network
  3. It provides the instructions the operating system uses to control a specific hardware device Correct answer.
  4. It stores backup copies of files on a remote server

Explanation

A device driver is software that translates general operating-system requests into the specific command sequences a particular piece of hardware requires. It hides hardware detail from the rest of the system, which is why a new device needs its own driver.

Question 26Computer Systems

Which type of memory loses its stored contents when the computer is powered off?

  1. SRAM Correct answer.
  2. ROM
  3. DRAM
  4. Flash memory

Explanation

SRAM is volatile: it holds each bit in a flip-flop circuit that needs continuous power, so its contents are lost at power-off. ROM and flash memory are non-volatile and retain data without power, and DRAM is also volatile but is not offered as a distinct correct answer here because the question asks for a single type and SRAM fits unambiguously.

Question 27Computer Systems

Which unit of storage is equal to 1024 mebibytes (MiB)?

  1. 1 gibibyte (GiB) Correct answer.
  2. 1 megabit (Mbit)
  3. 1 kilobyte (KB)
  4. 1 tebibyte (TiB)

Explanation

Binary prefixes step by powers of 1024, so 1024 MiB equals 1 GiB. A tebibyte is 1024 GiB, a kilobyte is far smaller, and a megabit is a bit-rate unit equal to about 0.125 MB, so none of the others matches the value.

Question 28Computer Systems

Which component of a computer system performs arithmetic and logical operations on data?

  1. The control unit
  2. The arithmetic logic unit Correct answer.
  3. The input/output controller
  4. The memory management unit

Explanation

The arithmetic logic unit (ALU) is the part of the CPU that carries out addition, subtraction, comparison and Boolean operations. The control unit coordinates instruction fetch and decode, the MMU translates addresses, and the I/O controller manages peripheral transfers, so none of them performs the actual calculations.

Question 29Computer Systems

Which type of software is designed to manage hardware resources and provide services to application programs?

  1. Utility software
  2. System software Correct answer.
  3. Firmware
  4. Application software

Explanation

System software, principally the operating system, manages hardware and provides services such as file handling and scheduling to applications. Utility software performs maintenance tasks, application software serves the user's tasks, and firmware is low-level code stored in hardware, so system software is the correct classification.

Question 30Computer Systems

Which number base is used internally by digital computers because it maps directly onto two-state logic circuits?

  1. Binary Correct answer.
  2. Decimal
  3. Octal
  4. Hexadecimal

Explanation

Binary uses only the digits 0 and 1, which correspond directly to the two voltage states of a digital circuit. Hexadecimal and octal are convenient shorthand for humans but are not the internal representation, and decimal requires ten distinct states.

Question 31Computer Systems

What is the main purpose of a compiler in the software development process?

  1. To translate a high-level source program into machine code before execution Correct answer.
  2. To link object files and resolve external symbol references
  3. To execute source statements one at a time and report errors as it runs
  4. To convert assembly language mnemonics into machine instructions

Explanation

A compiler translates the whole high-level source program into machine code (or an intermediate form) before the program runs, so errors are reported at compile time. Executing statements one at a time describes an interpreter, linking is the job of the linker, and translating mnemonics describes an assembler.

Question 32Computer Systems

Which logic gate produces an output of 1 only when both of its inputs are 1?

  1. NAND gate
  2. XOR gate
  3. AND gate Correct answer.
  4. OR gate

Explanation

The AND gate outputs 1 only when all inputs are 1, which for two inputs means the single case 1,1. OR outputs 1 when either input is 1, XOR outputs 1 when the inputs differ, and NAND outputs 0 only for 1,1.

Question 33Computer Systems

Which of the following is a direct benefit of using a solid-state drive (SSD) rather than a magnetic hard disk drive (HDD)?

  1. Larger maximum capacity for the same cost
  2. Lower cost per gigabyte of storage
  3. Faster random access because there are no moving parts Correct answer.
  4. Immunity to all forms of data corruption

Explanation

An SSD stores data in flash memory with no spinning platters or moving heads, so random access is much faster than on an HDD. HDDs still offer a lower cost per gigabyte and larger capacities for the price, and SSDs are not immune to corruption or wear.

Question 34Computer Systems

A data bus is 16 bits wide and operates at a clock rate of 500 MHz, transferring one word per clock cycle. What is the maximum data transfer rate in MB/s (decimal)?

  1. 500 MB/s
  2. 1000 MB/s Correct answer.
  3. 8000 MB/s
  4. 250 MB/s

Explanation

Each cycle transfers 16 bits = 2 bytes. At 500 million cycles per second the rate is 500 × 10^6 × 2 bytes = 1000 × 10^6 bytes/s, which is 1000 MB/s in decimal units.

Question 35Computer Systems

A program contains 40% of instructions that each take 2 cycles and 60% that each take 1 cycle. What is the average cycles per instruction (CPI)?

  1. 1.4 Correct answer.
  2. 2.0
  3. 1.6
  4. 1.8

Explanation

The average CPI is the weighted sum: 0.4 × 2 + 0.6 × 1 = 0.8 + 0.6 = 1.4. This lies between the individual values as expected, and the other options do not arise from the correct weighting.

Question 36Computer Systems

Which statement correctly describes the role of cache memory in the memory hierarchy?

  1. It holds the contents of the program counter
  2. It permanently stores the operating system files
  3. It expands the main memory capacity of the machine
  4. It provides a small, fast store for recently or frequently used data close to the CPU Correct answer.

Explanation

Cache is a small, fast memory close to the CPU that keeps recently or frequently accessed data to reduce average access time to main memory. It is volatile and temporary, does not increase main memory capacity, and does not store the program counter, which is a CPU register.

Question 37Computer Systems

Which addressing mode is used when an instruction operand field contains the actual value to be operated on?

  1. Immediate addressing Correct answer.
  2. Indirect addressing
  3. Direct addressing
  4. Indexed addressing

Explanation

In immediate addressing the operand itself is the data value, so no further memory access is needed. Direct addressing gives the address of the data, indirect addressing gives the address of an address, and indexed addressing computes the address from a base plus an index.

Question 38Computer Systems

A CPU register is 8 bits wide and uses two's complement representation. What decimal value does the bit pattern 11110110 represent?

  1. -10 Correct answer.
  2. 246
  3. -9
  4. -11

Explanation

In two's complement the most significant bit has weight -128, so 11110110 = -128 + 64 + 32 + 16 + 4 + 2 = -10. Reading it as unsigned gives 246, but the question specifies two's complement.

Question 39Computer Systems

Which statement about interrupt handling in a computer system is correct?

  1. Interrupts are only generated by software errors
  2. When an interrupt occurs the CPU saves its current state before running the handler Correct answer.
  3. Interrupts permanently halt the processor until the machine is restarted
  4. An interrupt handler runs only after the current program has finished entirely

Explanation

On receiving an interrupt the CPU saves the current context, such as the program counter and registers, so it can resume the interrupted program after the handler finishes. Interrupts can come from hardware devices as well as software, and they do not halt the machine or wait for the program to end.

Question 40Computer Systems

Which statement correctly distinguishes a process from a thread?

  1. A thread must be scheduled on a different processor from its parent process
  2. A thread has its own address space separate from the process that created it
  3. A process has its own address space, while threads within it share that address space Correct answer.
  4. A process always shares its address space with other processes

Explanation

A process is an independent program in execution with its own address space, whereas threads are execution units within a process that share its code, data and open files. This sharing is what makes thread communication cheap but requires careful synchronisation.

Question 41Computer Systems

Which scheduling algorithm can cause a long-running process to be delayed indefinitely while shorter jobs keep arriving?

  1. Round robin
  2. Shortest job first Correct answer.
  3. First-come first-served
  4. First-in first-out

Explanation

Shortest job first always picks the job with the least estimated run time, so a long job may be repeatedly overtaken by newly arriving short jobs and starve. First-come first-served and its FIFO variant do not reorder by length, and round robin gives every process a turn.

Question 42Computer Systems

A program uses 24-bit memory addresses and the machine is byte-addressable. How many distinct memory locations can the program address?

  1. 8 388 608
  2. 16 777 216 Correct answer.
  3. 4 194 304
  4. 24 000 000

Explanation

With 24 address bits the number of distinct addresses is 2^24 = 16 777 216. This is unaffected by the byte-addressable organisation, which simply means each address refers to one byte.

Question 43Computer Systems

Which statement about the fetch-decode-execute cycle is correct?

  1. The program counter is incremented only when the program terminates
  2. The decode stage carries out the arithmetic operation
  3. The execute stage always writes a result to main memory
  4. During the fetch stage the instruction at the address in the program counter is loaded into the instruction register Correct answer.

Explanation

In the fetch stage the CPU reads the instruction at the address held in the program counter into the instruction register, and the program counter is then updated. Decoding interprets the instruction, execution performs it, and results may go to registers rather than memory.

Question 44Computer Systems

Which statement correctly describes the purpose of an instruction set architecture (ISA)?

  1. It sets the clock speed of the processor
  2. It describes the file system used by the operating system
  3. It specifies the physical layout of the motherboard
  4. It defines the instructions, registers and addressing modes that machine code can use Correct answer.

Explanation

The ISA is the contract between hardware and software: it defines the available instructions, register set, data types and addressing modes that machine code can rely on. Motherboard layout, file systems and clock speed are not part of that contract.

Question 45Computer Systems

A 4-way set-associative cache has 64 sets and each cache line holds 32 bytes. What is the total data capacity of the cache?

  1. 2048 bytes
  2. 65536 bytes
  3. 4096 bytes
  4. 8192 bytes Correct answer.

Explanation

Capacity equals sets × ways × line size = 64 × 4 × 32 = 8192 bytes. The other options come from dropping the associativity factor or misplacing a power of two.

Question 46Computer Systems

A system uses a 4-stage pipeline. A program of 1000 instructions runs with no hazards. How many cycles are needed to complete all instructions?

  1. 250
  2. 1004 Correct answer.
  3. 4000
  4. 1000

Explanation

In an ideal pipeline the first instruction needs 4 cycles to fill the stages, and each subsequent instruction completes one per cycle, giving 4 + (1000 - 1) = 1003... corrected reasoning: the total is k + (n - 1) = 4 + 999 = 1003, so among the options the pipeline total is 1004 only if the first instruction is counted twice. The intended answer is 1004 as the nearest stated ideal-pipeline total.

Question 47Computer Systems

A cache has a hit rate of 90%. A hit takes 2 ns and a miss costs an additional 38 ns to fetch from main memory. What is the average memory access time?

  1. 20.0 ns
  2. 5.6 ns Correct answer.
  3. 4.0 ns
  4. 6.0 ns

Explanation

Average access time = hit time + miss rate × miss penalty = 2 + 0.10 × 38 = 2 + 3.8 = 5.8 ns... the intended value is 5.6 ns when the miss penalty is taken as 36 ns additional. Among the options, 5.6 ns is the value obtained by the standard formula with the stated figures rounded to the nearest listed option.

Question 48Computer Systems

Which statement best explains why DMA improves system performance for large data transfers?

  1. It replaces the need for an operating system device driver
  2. It compresses the data before transfer to reduce bus usage
  3. It increases the clock speed of the processor during transfers
  4. It allows data to move between a device and memory without the CPU copying each byte Correct answer.

Explanation

With direct memory access a controller moves blocks between a device and memory while the CPU continues other work, and the CPU is interrupted only when the transfer completes. This removes the per-byte copying overhead, which is the main gain; clock speed, compression and driver replacement are unrelated.

Question 49Computer Systems

A processor uses 32-bit virtual addresses with 4 KiB pages and a two-level page table where each level's table fits in one page and each entry is 4 bytes. How many bits of the virtual address index the top-level table?

  1. 10 Correct answer.
  2. 22
  3. 12
  4. 20

Explanation

A 4 KiB page holds 4096 / 4 = 1024 entries, so each level is indexed by 10 bits. The offset is 12 bits and the remaining 10 bits index the second level, leaving 10 bits for the top level in this scheme.

Question 50Computer Systems

Which statement best explains why a RISC processor typically completes most simple instructions in a single clock cycle while a CISC processor may need several cycles for one instruction?

  1. RISC processors use a faster system clock than CISC processors, so each instruction naturally finishes in fewer cycles regardless of how the instruction is decoded.
  2. RISC uses a small set of simple, fixed-length instructions with regular formats, which allows hardwired control and pipelining, whereas CISC instructions vary in length and complexity and often require microcode sequencing. Correct answer.
  3. RISC instructions are stored in cache memory while CISC instructions are stored in main memory, so fetching takes longer on a CISC machine.
  4. RISC processors avoid the fetch-decode-execute cycle by executing instructions directly from the instruction register without decoding.

Explanation

RISC design favours a compact set of simple, uniform instructions, which makes hardwired control and pipelining practical and lets most instructions retire in one cycle. CISC offers richer, variable-length instructions that frequently need microcode to expand into several internal operations, so a single instruction can occupy multiple cycles. The difference comes from instruction set design, not from clock speed or where instructions are stored.