Basic Computer Organization:
A computer system is composed of the hardware and the software. Computer hardware are those parts which can be physically seen, touched and felt whereas the software are the ones responsible for making the system work, the software are there in the systems and can’t be physically touched seen and felt but there presence lets the whole computer system to function in a coordinated manner.
The software can be the systems software or the application software. The system software are designed to make more effective use of the computer. The programs included in a systems software package are referred to as the operating system like Windows, Linux, MAC and for small hand held devices these are Android and IOS etc. Other examples of system software are compilers, assemblers.
An Operating System (OS) acts as an interface between computer hardware components and the user. Every computer system must have at least one operating system to run other programs. The OS helps you to communicate with the computer without knowing how to speak the computer’s language. It is not possible for the user to use any computer or mobile device without having an operating system. It also helps in resource sharing. Applications like Browsers, MS Office, Notepad Games, etc., need some environment to run and perform its tasks.
Computer software is set of instructions supported over a wide range of operations along with the data that are operated by the computer for various tasks. Computer programs are set of instructions written to carry out a specific task.
Computer hardware of a basic computer system is shown in figure-1. It consist of three major block-CPU, Control Unit and number of registers. The CPU contains the arithmetic and logic unit, the control unit generates various timing and control signals for various operation including the instruction fetch and execute operation, and the registers are used as temporary storage of data and partial results.
The memory unit is used as storage for the computer programs and data. The memories is of the two types these are the primary(or internal) memory in the form of RAM and ROM and secondary or external memory like floppy hard disk, CDROM, disk(obsolete now) etc. The IOP is used to access the input output devices. When dealing with computer hardware it is customary to distinguish between what is referred to as computer organization, computer design, and computer architecture.
Computer organization is concerned with the way the hardware components operate and the way they are connected together to form the computer system. Compute Design is concerned with the hardware design of the computer. After describing the specification the computer engineer converts this specification in implantation whereby he describes what hardware is to be used and how those parts must be connected. Computer Architecture is concerned with the structure and behavior of the computer as seen by the user. It includes the information formats, the instruction set, and techniques for addressing memory.
The hardware components are designed using discrete parts such as logic gates to form the combinational and sequential components. Combinational components are the once whose response at any time depends on the inputs or stimuli present at that instant of time. Examples are half adder, full adder, multiplexers, decoders, arithmetic and logic units and various code converters. The sequential components include the latch, flip-flops, registers, counters and control unit etc. We will briefly discuss these in the next section.