Computer and Motherboard Computer
A computer is programmable machine that receives input, stores, manipulate data, and provides output in a useful format.
Computer takes input from input devices and then compute in CPU and stores in memory and sends output to output devices. The most common device for input is the keyboard. When you type, you are putting information into the computer, which is known as input. The most common device for output is the monitor. These input output devices are connected through I/O Ports.
A computer system unit contains many parts. As shown in Figure 1.2(a) and Figure 1.2 (b).
Motherboard :
The motherboard is the main circuit board of a computer. It is also known as the main board or system board. Typically, the motherboard contains the CPU, BIOS, memory, mass storage interfaces, serial and parallel ports, expansion slots, and all the controllers required to control standard peripheral devices, such as the display screen, keyboard, and disk drive. Collectively, all these chips that reside on the motherboard are known as the motherboard's chipset. The motherboard can be thought of as the "back bone" of the computer.
CPU :
- stores data and instructions waiting to be used.
- follows changeable instructions.
- does input, processing, and output.
Memory :
I/0 Ports-
In this sub-section, we will study about I/O ports.
Ports and Connectors : A port is a connector located on the motherboard or on a separate adapter. This we will discuss in following sub section.
As shown in figure 1.2 an internal view of some of the I/O ports. On the back of computers are several I/O (or Input/output) ports. Above, on the very top are two PS/2 ports, normally used for mouse and keyboard connections. Below that are the USB, (or Universal Serial Bus), ports. Below those are two serial ports beside a long parallel port that is often used to connect to a printer. On the bottom right is a game port for joysticks or other game controllers. On the bottom left is a microphone hook up, a speaker hook up, and an additional hook up for another sound input device like a musical keyboard.
I/O ports are there to connect to I/O devices. There are various I/O devices which are discussed in the next subsection:
I/O Devices
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| Few I/O devices are given Table 1.1. |
- is used to type data into the computer.
- is most common input device.
- has special keys for giving the computer commands.
- Commands tell the computer to do something, like save the file.
- These special keys are called command or function keys.
Types of Keys
How keyboard connects to a computer?
Computer Keyboard can connect with a computer through a cable or signal (wireless connection). Until recently, a keyboard used to connect with the standard PS/2 type or Serial.
Now, this trend has changed and the connection is replaced by USB (universal Operating System serial bus) and wireless connectors. Most modern PCs (motherboards) even don‘t have PS/2 connectors, only USB
Since, there is no cable connection with main PC, wireless keyboard gets power from battery or a/c power connection. This is the side effect of wireless keyboards; you often have to change battery.
Mouse
The mouse is a small device used to point to a particular place on the screen and select in order to perform one or more actions. It can be used to select menu commands, size windows, start programs etc. The most conventional kind of mouse has two buttons on top: the left one being used most frequently
