BCA 1st Year Components of a Computer System Notes Study Material
Semester Wise BCA 1st Year Components of a Computer System Notes Study Material: If you choose to do a Bachelor of Computer Application, it is BCA. BCA is a three-year program in most universities. After getting enrolled for BCA, There are certain things you require the most to get better grades/marks in BCA. Out of those, there are BCA Notes and BCA Semester Wise Notes Study Material, BCA Question Answers along with BCA Previous Year Papers. At gurujistudy.com you can easily get all these study materials and notes for free.
If you are a BCA Student there is a single-stop destination as far as preparation for BCA Examination is concerned. Here in this post, we are happy to provide you with the Topic Wise & Chapter Wise BCA 1st Year Components of a Computer System Notes Study Material.
BCA 1st Year Components of a Computer System Notes Study Material
Components of a Computer System
1. Input Unit: The computer system needs data and instructions to perform any processing; without these things, it cannot do anything. Data and instructions are entered into a computer system with the help of an input unit. Input devices (such as Keyboard, Mouse, Touch Screen, etc.) are used to provide data and instructions to the computer.
The following functions are performed by an input unit:
(a) It accepts (or reads) the data and list of instructions (i.e., program) from the outside world (i.e., from the input devices).
(b) It then converts these instructions and data into a form that the computer can understand (i.e., in binary form).
(c) It finally supplies the converted data and instructions to the computer system for further processing.
2. Output Unit: The output unit supplies information and results of computation to the outside world (i.e., to the user or other computer). It links the computer with the user. Devices of output units Monitor and Printer etc.) are used to provide output to the user.
The following functions are performed by the output unit:
(a) It accepts the result produced by the computer in binary form.
(b) It then converts these coded results into a human-acceptable (readable) form (i.e., in English, Hindi, or other similar languages).
(c) It finally supplies the converted results to the outside world (i.e., to the user).
Components of a Computer System
3. Storage Unit: The process of saving data and instructions in computer memory is known as storing. Storage devices are used to do this work. The functions of the storage unit are:
(a) The data and instructions required for processing (received from the input unit).
(b) Intermediate results of processing.
(c) Final results of processing before these results are released to an output unit. The storage unit of all computers is comprised of the following two types of storage:
(i) Primary Storage: The primary storage (or main memory) is used to hold instructions and data, intermediate results of processing, and recently produced results of processing, which the computer is currently working on. Primary storage (such as RAM, Cache memory) can hold information only while the computer system is ON. Moreover, primary storage normally has limited storage capacity.
(ii) Secondary Storage: Secondary storage (or auxiliary storage) is used to solve the problems of primary storage. The secondary storage (such as Hard Disk, Compact Disk, Floppy Disk, Pen Drive, etc.) can retain information even when the computer system is switched OFF. It is normally used to hold the program instructions and data on which the computer is not working currently but needs to hold them for processing later. Its storage capacity is not limited. A huge volume of data can be stored on it.
Components of a Computer System
4. Central Processing Unit (CPU): The CPU is the brain of the computer system. In a computer system, all major calculations and comparisons are made inside the CPU and the CPU is also responsible for activating and controlling the operations of other units of a computer system. The two components of the CPU are:
(a) The arithmetic logic unit.
(b) The control unit.
(a) Arithmetic Logic Unit (ALU): ALU is the place, where the actual execution of the instructions takes place. ALU performs the four basic arithmetic operations (Add, Subtract, Multiply and Divide) and logic operations or comparisons are less than, equal to, and greater than, etc.).
As and when needed, the data and instructions are transferred from the primary storage (such as RAM) to the ALU, where processing takes place. Intermediate results generated in the ALU are temporarily transferred back to the primary storage until needed later. Hence, data may move from primary storage to ALU and back again to storage, many times, before the processing is over.
(b) Control Unit (CU): Control Unit controls, and supervises all the activities of a computer and monitors the execution of any program i.e., a set of instructions) processed.
The control unit coordinates and controls the activities of the different components of the computer system in much the same way that the brain directs the actions of the body.
Its primary function is to select and interpret instructions and to send appropriate signals to other units in the computer for their execution.
Method of Transmission of Data Across Different Units
There are some types of messages that might be sent. like “The CPU wants to get the contents of one cell in memory”. Every cell in the memory has an address, what to transfer is data and the CPU does this work on the execution of a particular instruction.
Bus interface: Communication between devices always requires these three components, Sound is a set of lines between different units (collectively known as a bus).
The set of lines used for transmitting instruction is the control bus, another set of lines for identifying addresses is the address line and a third set of lines to move data between units is the data bus.
Chapter Wise BCA 1st Year Computer Fundamentals and Office Automation Notes Study Material