UNIT 2 TASK 1 (P1)

Develop a series of illustrated blogger entries which explain each item listed below and what is each of their functions. In addition, you must identify communication between components.

Internal system unit components:

Processor: A Computer Processing Unit is a piece of hardware inside of the computer sends and carries out information to the rest of the system or computer program. The CPU is basically the brains of a computer. It can carry out basic arithmetic and logic and also the inputs and outputs of the computer system. All instructions the user gives the computer it must go through the CPU first, for example for me to write this text, all the letters that I type on the keyboard to appear on-screen needs to go through the CPU to 'process' the information. The CPU can also be referred to as a processor or a central processor unit.
Normally a CPU has a different components. The first component is the arithmetic logic unit or ALU and this carries out simple arithmetic and logic operations. The second is the control unit or CU. This manages a number of different components in the computer like reading and interpreting instructions from memory and then turns them into a series of signals to activate other parts of the computer. The third is a high speed memory that can copy and retrieve instructions, this is called the cache.
Over time CPU's have changed into microprocessors and they can found on the computers motherboard.

Motherboard: A motherboard is a sheet of plastic that holds all of the circuits to connect all the components of the system. A motherboard is one of the most important parts of a computer system as it holds most of the crucial components together which includes the CPU, memory, the input and output sockets., BIOS and mass storage, interfaces, serial and parallel ports, expansion ports and controllers that are needed to control peripheral devices which are the display screen, keyboard and the disk drive. All the chips that are on the motherboard are known as the motherboard's chipset.
Power connectors: the computer needs to operate and for that to happen it needs power. The power connector is a 20 or 24 pin connector that can be found near the right edge of the motherboard or close to the processor sockets. The main power supply is connected her e and provides power to the motherboard and its components. Newer motherboards have an extra 4 or 8 pin connector to give power straight to the processor.
Memory slots: They can be found on the upper right of the motherboard and they are there to store the computers memory. Depending on the motherboard, memory slots can vary it can hold from 2 to 8 memory slots.
Video card slot: or also know as a graphics card, this can be found on the right below the processor. It is rectangular in shape with one or more ports so it can easily be connected to video displays and other devices. The video card is an expansion card that lets the computer send graphical information to a display device like a monitor, TV or a projector. Some motherboards can only support a limited amount of video cards and many modern computers don't have video expansion cards, instead they have GPU's integrated directly onto the motherboard, this then makes the computer less expensive but also has a low graphics system.




BIOS: This stands for Basic Input Output System or Basic Integrated Operating System and it is a software that is stored on a memory chip on the motherboard. The BIOS gives instructions to the computer to do a number of basic functions like booting and keyboard control. It is also used to configure and identify the hardware in the computer like the hard drive, optical drive, CPU and memory and so on.

Power Supply: Power supply or power supply unit is hardware that changes the power that is provided from the outlet into power that can be used for parts inside the computer. It can be found inside the back of the case.





Fan and Heat Sink: Nearly all computers have heat sink and this keeps the CPU cool and prevents it from overheating. Sometimes the heat sink itself can over heat and this can happen when the CPU has been running at full capacity for long periods of time and the air around it is too hot. A fan is used with both the heat sink and CPU so it c an keep both of them at an appropriate temperature. The fan moves the hot air away from the heat sink and away from the computer. CPU's have a thermometer built in and keeps track of the processors temperature, if it gets too hot then the fan or fans near the CPU then speeds up to keep the CPU cool.

Hard Drive and the Configuration/Controller (SATA or IDE or EIDE): A hard drive or other wise known as a hard disk drive is the main data storage device on the computer and it is usually the largest device in the computer. The operating system, software and most data and files are stored in here.
The hard drive is usually found on the computer as the C drive, technically it isn't the correct term for the drive but it is commonly known as it, there are other letters that represent the other drives that can be connected, for example E, D and F.
The back end of the hard drive has a port for a cable which connects to the motherboard, but the cable depends on the drive and it is almost always included when buying the hard drive. In the port is has connections to the power supply so power can flow through the device when needed.
IDE: IDE stands for Integrated Drive Electronics and it is a standard connection for storage devices inside the computer. Generally its referred to the different types of ports and cables. This is an old standard and it has been replaced by SATA.
SATA: This stands for Serial Advanced Technology Attachment. And this is currently used after replacing IDE and is used to connect to the hard drive or SSD and to the rest of the computer.

Ports USB and/or Parallel and/or Serial: A USB port is a cable connection port on computers and other electronics. They allow devices to connect to the PC. USB stands for Universal Serial Bus it also allows data to transfer between devices and can also supply electricity across the cable to power a device i.e. connecting a mobile phone via PC and allowing the mobile to charge.
Parallel Ports: Centronics were the first and original company to make parallel ports hence where the name Centronics interface or Centronics connector came from. It could be found on the back of IBM compatible computers as a 25 pin connector and it was commonly used to connect printers to the computer. Today the parallel port has been replaced by USB's but the parallel port can still be used for connecting a printer, scanner and some external drives.
Serial Ports: Just like parallel ports it was made to be compatible with IBM computers and it was used to connect a serial device to a computer and it was able to transmit one bit of information at a time. Also like parallel ports it was replaced by faster serial ports and USB ports and are now rarely used. A serial port can still be used to connect a mouse, modem, network and a printer.

Internal Memory RAM, ROM and Cache: RAM stands for Random Access Memory and it is a storage that allows information to be stored and accessed quickly from random locations. Because it is accessed randomly and not in sequence like a CD or a hard drive the computer can access what it needs faster than it would if it was a read only drive. RAM needs power in order for it to run and to keep the data accessible. If power is lost then all of the data is lost also. As the computer starts to load parts of the OS and drivers are loaded into the memory and this allows the CPU to process information faster and also the computer will load faster. After it has loaded each program that you open and view will be loaded into the memory whilst the program is running. If too many programs are open the computer will swap the data in the memory between the RAM and the HDD.
ROM: ROM stands for Read Only Memory and it is a type of built in memory that is used in computers and other electronic devices. As the name states it can only read the data that has been stored. ROM is mostly used for firmware updates. ROM can also be used in video game consoles which can allow the system to run multiple games on one console.
Cache: This is a high speed access ares that can be used for a section of main memory or used a storage device. There are two main types of cache, memory cache and disk cache. Memory cache is a section on memory of SRAM and it is effective because most programs can access the instructions over and over. It keeps as much information as it can so it can avoid using DRAM which is much slower. Just like memory caching, disk caching is used to access data. and instead of using SRAM the disk cache uses conventional main memory. When a program needs to access the data from a disk it checks the disk cache first to make sure and see if all the data is there. Disk cache can improve application performance because accessing a byte of data in the RAM is a thousands times quicker than accessing it from the hard drive.














Specialized Cards Network and/or Graphic Cards: A network card is a piece of computer hardware and is it made to allow computers to communicate over a computer networks. This card has two LED indicator lights, green and orange. Green means that the card is receiving information and power and orange, or red, shows that the network is sending or receiving information. For data to be sent to the card it needs and uses a transceiver which turns the parallel data into serial data. Each network card has a unique address linked to it and this is called a MAC address and it is put there by the manufacturer, this helps identify the card all over the world. The network card must be compatible with the computer it self and also have the correct socket for the cable it needs because each card needs a specific cable.
Graphics Card: A graphics card is a component on the motherboard inside the computer that generates signals that are sent to the monitor like texts and pictures that are displayed. Most PC's have a physical card that is inserted into a PCI slot on the motherboard hence why it is called a card. Two dimensional graphics are used when you open a web browser or opening work or a spreadsheet from your documents. The resolution determines how many dots are used to create and draw the image on the screen. For example 640x480 pixels means that the whole screen needs to have 307,200 little dots in 640 columns and 480 rows. The more dots used, the finer the details are which means that higher resolutions have great detail and better image quality.















Peripherals:

Printer: A printer is an external device for a computer that can print paper documents which can include text documents, images or both. There are two common types of printers - inkjet and laser printers. Inkjet are typically used by consumers and laser printers are mostly used in businesses. In order for the printer to print a document, electronic data is sent from the computer to the printer and many programs like Microsoft Word and image editing programs like Adobe Photoshop have a 'print' option in the File menu. When you click this option you will be shown a print dialog box and this box allows you to choose different printing options depending on your preferences or what you want. Once you have selected your options then the settings are sent to the printer before the document has sent. In order for the printer to physically print it needs to be turned on and also connected to the computer. Modern computers can now be connected through a USB port using a standard USB cable. However some can be connected over a Wi-Fi network. You can also have more than one printer connected but this only works if the correct drivers are installed.







Scanner: A scanner is a device that scans images and text documents. When a document has scanned it is converted into a digital format and this creates an electronic version of the document that can be viewed and edited. Most scanners are known as a flatbed device and that means that they have a flat scanning surface which is ideal for photographs, magazines and other types of documents. Most flatbed scanners have a cover that can lift up so bigger objects can be scanned like books. Another type of scanner is a sheet-fed scanner which only accepts paper only. Scanners work together with a computer software program which collects data from the scanner. Scanners have basic scanning software which allows it to configure, initiate and import scans. Scanning plug-ins can also be installed on the computer which lets various programs to import scanned images directly.









Twisted Pair Cabling: Twisted pair cabling is a type of cable that is made when you put two separate insulated wires together in a twisted pattern and running them parallel to each other. This type of cable is widely used in different types of data.
It is often used to avoid certain signal interference. There is also two types of twisted cabling, one is unshielded twisted pair (or UTP) and shielded twisted pair (or STP) and they are used in different kinds of installations. UTP is commonly used in Ethernet connections and STP is used in a number of networks to prevent crosstalk and electromagnetic interference.

Backing Storage:
Pen drive: A Pen drive is a portable USB and it is used to transfer files like audio, video and data files from a computer to another device that has a USB port and the pen drive is compatible with the OS. Other names for this may be flash drive, jump drive and thumb drive.

Hard drive: A hard drive or also known as a hard disk drive is the computers main storage device and it permanently stores data on the computer. Most hard drives can be found in the internal bay at the front of the computer and it is connected to the motherboard either by using ATA or a SATA cable and power cable.




BUS
Bus is a data connection between two or more devices that are connected to the computer. For example the bus enables the computer processor to communicate with the memory or the video card to communicate with the memory. It has multiple wires or signal lines that have addressing information that describes the location of where the data is being sent or where it has been received. Each of the wires carries a small bit of information, which means that the more wires the bus has the more information that it can carry and address, for example a computer that has a 32 bit address bus it can address 4 GB of memory and if it has a 36 bit bus it can address 64 GB of memory.
A bus can be either serial or parallel but today all computers use both types, internal or local bus and external or also known as the expansion bus. An internal bus enables an communication between internal components like a computer graphics card and memory and an external bus is capable of communicating with external components, hence the name, like a USB. The buses speed is measured in MHz and the throughput is measured in bits per second or megabytes per second.


Sources:

http://www.wisegeek.com/what-is-a-pen-drive.htm
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