THE COMPONENT PARTS OF A MICRO COMPUTER
The Basic Components parts of a computer are as follows
1. The Alpha-numeric keyboard
2. The Display screen (MONITOR)
3. The Disk-Drives (RECORDING/STORAGE DEVICE)
4. The Central Processing Unit (CPU)
5. The Printer.
1. Alpha-Numeric Keyboard:
The micro-computer keyboard is similar to that of a typewriter. However,
you will find a few differences between the micro-computer and the
typewriter keyboard. The micro-computer has some special function keys that
cannot be found on the typewriter. It also has a 12 keypad for arithmetic
calculations. Depressing a key produces an electric signs that the micro-
Computer can understand. The computer responds by sending back signal
which are transformed into characters, letters, numbers and symbols or a
display screen and also on paper if the printer is being used.
The micro-computer keyboard can be attached or detached from the CPU. When the keyboard is detached, it is called a movable keyboard and can be placed wherever it is most convenient for the operator.
2. Display Screen (MONITOR)
Display screen are known by more than one name. Some prefer to call it VDT – Video Display Terminal others may call it CRT – Cathode Ray-Tube at other times ut can also be called a monitor. The monitor can be in black and white or colour. A full-age display might show up to 54 lines but all the 54 lines cannot show at a time on the screen. To view the lines, the operator must be use the scroll key. The modern screens have antiglare surface and the brightness can be adjusted to suit the operator. The keyboard together with the screen is called a TERMINAL or a WORKSTATION.
3. THE DISK-DRIVES (RECORDING/STORAGE DEVICE)
As we keyboard text on the computer, it shows on the screen and it is also held in the internal memory. If the power is turned off accidentally, the information on the temporary memory would be lost. This is why it is necessary for the operator to save/store the information on the storage medium intermittently as the information is being fed into the computer.
The most common storage media are the floppy disks and the hard disks. Others are the bubble memory and the optical disks. However, the information can only be recorded on the magnetic media through a DISK DRIVE.
4. THE CENTRAL PROCESSING SYSTEM UNIT (CPU)
This is the intelligence/logic capability of the computer system. It can be compared to the human brain. However, the computer systems cannot function without instructions (programmes). There are two typers of software programmes Application softwares and operating system software.
The HARDWARE is the physical equipment that can be seen and touched.
The CENTRAL PROCESSING UNIT can be divided into three namely:
1. THE MAIN MEMORY
The main memory is also called the Random Access Memory or Internal Memory or Immediate Access Memory. The main memory stores programmes and data. Instructions are also stored in the main memory.
2. THE CONTROL UNIT
It controls and co-ordinate the activities of the hardware;
3. THE ARITHMETIC AND LOGICAL UNIT (ALU)
The Arithmetic Unit performs arithmetic operations such as additions, subtraction, multiplication and division while the logical unit performs logical operations such as comparison of numbers like three is greater than four (3 4). It is the logical unit that will give the answer.
4. PERIPHERAL UNITS
The unit can be divided into three namely:
1. INPUT DEVICES
Input device converts characters into machine readable format. It sends the information to the central processing unit through any input medium. Examples of input media are: Mouse Keyboard, light pen, punch card, Magnetic tape and Magnetic disk. Optical character readers (OCR) voice recognition units and devices used to transmit over telephone lines (Modem).
2. OUTPUT DEVICES
Output device converts binary information into human readable format. It collects information from the central processing unit (CPU) to the outside World. Examples of output devices are: the printers, VDU-Visual display unit or Monitor.
3. AUXILLIARY STORAGE DEVICES
Auxiliary storage device is also called Secondary or External Storage Device. It stores programmes or data that are not currently in use. Examples of Auxiliary storage media are: hard disks, floppy disks, magnetic tape or paper tape.