IT solutions provider singapore, The instructions that form a particular program are stored within the primary storage, then brought into the central processing unit and executed. Conceptually, instructions are brought in and executed one at a time, although modern systems overlap the execution of instructions to some extent. Instructions must be in primary storage in order to be executed. The control unit interprets each instruction and determines the appropriate course of action.
IT solutions provider singapore Each instruction is designed to perform a simple task. Instructions exist to perform basic arithmetic, to move data from one place in the computer to another, to perform I/O, and to accomplish many other tasks. The computer’s power comes from the ability to execute these simple instructions at extremely high speeds, measured in millions or billions or trillions of instructions executed per second. As you are already aware, it is necessary to translate high-level language programs into the language of the machine for execution of the program to take place. It may require tens or even hundreds of individual machine instructions to form the machine language equivalent of a single high-level language statement.
Program instructions are normally executed sequentially, unless an instruction itself tells the computer to change the order of processing. The instruction set used with a particular CPU is part of the design of the CPU and cannot normally be executed on a different type of CPU unless the different CPU was designed to be instruction set compatible. However, as you shall see, most instruction sets perform similar types of operations. As a result, it is possible to write programs that will emulate the instruction set from one computer on a computer with a different instruction set, although a program written for the original machine may execute slowly on the machine with the emulator.
IT solutions provider singapore There are two major categories of software: system software and application software. System software helps you to manage your files, to load and execute programs, and to accept your commands from the mouse and keyboard. The system software programs that manage the computer are collectively known as an operating system, and differ from the application programs, such as Microsoft Word, or Firefox, or the programs that you write, that you normally run to get your work done. Windows and Linux are the best known examples of an operating system. Others include Unix, Mac OS X, Sun Solaris, and IBM z/OS
IT solutions provider singapore The operating system is an essential part of the computer system. Like the hardware, it is made up of many components. A simplified representation of an operating system is shown in Figure 1.9. The most obvious element is the user interface that allows you to execute programs, enter commands, and manipulate files. The user interface accepts input from a
IT solutions provider singapore The data that is manipulated by these instructions is also stored in memory while being processed. The idea that the program instructions and data are both stored in memory while being processed is known as the stored program concept. This important concept is attributed primarily to John von Neumann, a famous computer scientist. It forms the basis for the computer architecture that is standard to nearly every existing computer
IT solutions provider singapore In addition to the hardware requirement, your computer system also requires software. Software consists of the programs that tell the computer what to do. To do useful work, your system must execute instructions from some program
keyboard and, in most modern systems, a mouse, touch screen, or other pointing device. The user interface also does output presentation on the display. On some systems, the output display might IT solutions provider singapore be simple text, but more likely the display includes a graphical user interface with a windowing system, and various gadgets for manipulating the windows
The operating system’s application program interface (API), acts as an interface for application programs and utilities to access the internal services provided by the operating system. These include file services, I/O services, data communication services, user interface services, program execution services, and more