Components of a computer system Flashcards
What is a computer?
A machine that processes data, its purpose is to take in data, process it and then output it.
What are computer systems comprised of?
- Hardware
- Software
What is hardware?
The physical components of a computer system, like the CPU, motherboard or a printer.
What is software?
Is the programs that a computer systems runs, they tend to control a piece of hardware.
What are the two types of software?
- Application,
- System.
What is the difference between application and system software?
- Application software is software that is made for a very specific task, usually surrounding a single program. For example, web browsers, email clients and games.
- System software is software that supports the computer system and is needed for the device to run. For example, an OS.
What is an embedded system?
A combination of hardware and software inside another device. This embedded system cannot be changed by an average person and carries out a very specific function often times. For example, an oven.
What are the advantages of a embedded systems?
- Very small,
- Cheap to produce,
- Easier to design and build because it only does a limited number of tasks,
- More reliable, they tend to last longer with little maintenance,
- Uses more ROM which is cheaper than RAM,
- Requires less processing power, it is cheaper and generates less heat.
What hardware is used in embedded systems?
- Quite a lot ROM and has little RAM,
- Doesn’t tend to have secondary storage
- ROM and RAM are stored in the same chip so that costs and space is reduced,
- The processor is much weaker.
What hardware is mainly involved in a computer?
- Power Supply
- Fan
- CPU
- GPU
- Motherboard
- HDD
- RAM
- ROM
- Optical drive
What is the function of the power supply?
To give power to the motherboard and all the hardware components.
What is the function of the Fan?
Control the thermals of the PC.
What is the function of the CPU?
Controls the processing of data in the PC, carries out the fetch, decode execute cycle.
What is the function of the GPU?
Controls the graphics and rendering of images and videos in the computer.
What is the function of the Motherboard?
The main circuit board in the computer, it sends data between hardware as it is connected to everything.
What is the function of HDD?
This stores most of the computers data.
What is the function of RAM?
It is memory for the computer, it stores the applications that are currently being used and the memory is wiped once the PC is shut down (volatile memory)
What is the function of ROM?
It is Read only memory, this memory cannot be changed and is in little amount in an average PC. It stores start up instructions for the computer (BasicInputOutputSystem, BIOS).
What is the function of the Optical drive?
Controls CDs that enter the computer, allows the reading and writing of these CDs.
What characteristics effect the CPUs performance?
- Clock speed,
- Number of cores,
- Cache size and type.
What are the 5 main parts of the CPU?
- The control unit,
- The arithmetic logic unit (ALU),
- The cache,
- The clock,
- Buses.
What is the function of the control unit (CU)?
- The main controlling unit of the CPU,
- Its main function is to execute instructions by following the fetch execute cycle.
- Also controls the flow of data inside the CPU and outside,
- It also keeps track of memory addresses for the instructions for the cycle.
What is the function of the arithmetic logic unit (ALU)?
- Basically does all the calculations,
- It performs logic operations (and, or, not) and binary shifts,
- Registers temporarily hold calculation information for the ALU,
- It receives data from CU and Registers and performs operations on them and outputs it back to the registers.
What is the function of the cache?
- A very fast memory in the CPU, it is faster than the RAM but slower than registers,
- It stores regularly used data so that the CPU can access often used instructions so the fetch-execute cycle can happen more efficiently,
- Has a low capacity and is expensive compared to RAM because of its speed.
What is the function of buses?
- Collections of wires that are used transmit data between components of the CPU and to other parts of the CPU,
- A processor may have different buses for carrying: data, instructions and memory addresses.
What is the function of a register?
- It temporarily holds data in the CPU, it is a very fast memory and can read and write way faster than any other form of memory.
- There are different registers for storing different data.
What is Von Neumann’s architecture?
- A system were the CPU runs programs stored in memory,
- It has uses one set of memory for both instructions and data.
What is the function of memory in the CPU?
Holds program instructions and the program data for the fetch execute cycle.
What is the Fetch, Decode and Execute cycle?
Fetch:
- The control unit reads the memory address of the next CPU instructions,
- The instruction is copies over to the register in the CPU,
- The memory address in the CU then points to the address of the next instruction, ready for the next cycle.
Decode:
- the instruction that was copied from the memory is decoded by the CU,
- The control unit prepares for the next step, e.g. by loading other values into the register.
Execute:
-The instruction is performed,
- This could be anything like:
load data from memory, write data into memory, logic operations, change the address in the CU or halt the program.
