Instruction set and its types

Here I will discuss about the execution of the  instructions of the computer system

Instruction set

                A set of all instruction that a computer execute at one time is called instruction set. Different types of CPUs (processer) have different instruction set. Usually a CPU (processer) can executer 80-120 instruction.

Types of instruction set:

                                There are different types of instruction set are as follow:

1.       Data transfer instruction

2.       Arithmetic and logical instruction

3.       I/O instruction

4.       Control transfer instruction  

Instruction set

Data transfer instructions:

                                                A types of instruction set which is used to transfer data from one unit of the computer system to another is called data transfer instruction.  The CPUs provide different instruction for the data transferring. A programmer or user can use these instruction to transfer data from RAM to CPU registers and also back to RAM or to transfer the data to the output devices.

Arithmetic and logical instructions:

                                                                A  type of instruction set which is use to perform arithmetic instructions on the data is called arithmetic instructions. Arithmetic operations means all mathematical operation like addition,  subtraction, multiplication,  and division. All the arithmetic instructions are executed by ALU.

                                Those instructions that are used to perform an logical operation on the data are called logical instructions. The logical operation means that to compare the two values. All the logical operations are also executed by ALU.

I/O instructions:

                                A type of instruction set which is use to write and read data to and from the I/O devices are called I/O instructions. The I/O devices  are also know as peripheral devices. In peripheral devices keyboard, mouse, monitor and disks etc. The user or programmer can use these instructions to perform I/O operations.

Control transfer instructions:

                                                A type of instruction set which is use to transfer the execution control from one part of the computer to another during execution of the program is called control transfer instruction. These instructions are also used to execute or ignore a statement or set of statement after testing a condition.  Similarly, these instructions are also use to execute the statement repeatedly for a specified number of time.

Operating system

A collection of system software that control and co-ordinate the overall operations of the computer system is called operating system. For to do work, a computer need an operating system. Without operating system a computer cannot work. Without operating system a computer is like a car that have no fuel.

An operating system can perform different kind of operation. It is used

(i)                  To provide user interface

(ii)                To accept input from input devices

(iii)               To send output to output devices

(iv)              To manage the  application programs in memory

(v)                To organize data on the storage devices

(vi)              To perform memory management tasks

(vii)             To manage and control the I/O devices

Functions of Operating system

The operating system can perform different kind of operations. Some of these functions are as follow:

Manage hardware resources:

                                                        The operating system is used to manage the hardware resources. It has different hardware resources like input/output devices, CPU and disks etc.

Memory management:

                                                        The main memory plays a  very important in data processing. The data and instructions must be loaded into memory for execution. Different kind of the instructions are loaded for execution at the same time. The operating system manage these instructions and allocate to the memory.

Load and execute programs:

                                                        A program must be loaded into memory for execution. The operating system to do work to perform these operations.

Data security:

                        Data security is very important to protect our data. An operating system provide us security facilities.

Provide interface to the users:

                                                         Operating system provide us the interface to the user. User interface means how the user interact with the computer system to perform different operations. The operating system provide to types of interface;

(i)                  Command prompt

(ii)                Graphical user interface(GUI)