Ben's Blog

Posts

The Relationship between an Application program, the operating system and hardware

The relationship between an application program and the underlying hardware is usually shown in the form of a stack of layers as shown below: • 1.Application • 2.Application Programming Interface (API) • 3.Operating System • 4.Device Driver • 5.Hardware Most applications need to know how to talk to the operating system - which is why the operating system will provide a set of programming libraries knows as APIs or SDKs (Software Development Kits) for programmers to use when writing applications. The APIs sit between the operating system and the running application. The running application relies on the API to perform essential tasks on the computer by telling the operating system what it wants to do - which is why a program that is written to use Windows Vista APIs will not run on an Apple Mac without some kind of emulation or help. Because there are so many different pieces of hardware, it would be impossible for an operating system to support them all (especially the lesser...

A Description of the Boot Process

In order for a computer to successfully boot, its BIOS, operating system and hardware components must all be working properly; failure of any one of these three elements will likely result in a failed boot sequence. When the computer's power is first turned on, the CPU initializes itself, which is triggered by a series of clock ticks generated by the system clock. Part of the CPU's initialization is to look to the system's ROM BIOS for its first instruction in the startup program. The ROM BIOS stores the first instruction, which is the instruction to run the power-on self test (POST), in a predetermined memory address. POST begins by checking the BIOS chip and then tests CMOS RAM. If the POST does not detect a battery failure, it then continues to initialize the CPU, checking the inventoried hardware devices (such as the video card), secondary storage devices, such as hard drives and floppy drives, ports and other hardware devices, such as the keyboard and mouse, to ensu...

The Functions of a Computer Operating System

The operating system provides for several other functions including: • System tools (programs) used to monitor computer performance, debug problems, or maintain parts of the system. • A set of libraries or functions which programs may use to perform specific tasks especially relating to interfacing with computer system components. The operating system makes these interfacing functions along with its other functions operate smoothly and these functions are mostly transparent to the user.

The Environment Considerations in the Disposal of Computer Hardware and OH+S considerations in the use of computer equipment

The Environmental Considerations in the disposal of computer hardware and OH+S considerations in the use of Computer Systems A) Environmental Considerations in the disposal of computer system. There is large Carbon footprint in IT production industry but that can be reduced by re-use and re-deployment of redundant IT equipments known as Computer Recycling. Most of the environmental concerns with computers lie with the monitor, specifically its catode ray tube (CRT). On average, each color monitor contains 4 to 5 pounds of lead, considered hazardous waste when disposed of. There are other hazardous materials in computers, including mercury, cadmium (also known carcinogen), and hexavalen Chromium (cause high blood pressure, iron-poor blood, liver disease, and nerve and brain damage in animals). Over 314 million computers were thrown away at the end of 2007. Computer Recycling problem is, after upgrading computer system, most organizations store their old computers, which serve...

Internal hardware components, cost, image and function

CPU: $100-$1000 The Central Processing Unit (CPU) or the processor is the portion of a computer system that carries out the instructions of a computer program, and is the primary element carrying out the computer's functions. Memory: $50-$300 In computing, memory refers to the state information of a computing system, as it is kept active in some physical structure. The term "memory" is used for the information in physical systems which are fast (ie. RAM), as a distinction from physical systems which are slow to access (ie. data storage). Hard Disk: $100-$400 A hard disk drive[2] (hard disk,[3] hard drive,[4] HDD) is a non-volatile storage device for digital data. It features one or more rotating rigid platters on a motor-driven spindle within a metal case. Data is encoded magnetically by read/write heads that float on a cushion of air above the platters. DVD ROM: $20-$200 DVD, also known as Digital Video Disc or Digital Versatile Disc, is an o...

External hardware components and peripherals, cost, image and function

Monitor: $100-$300 A monitor or display (sometimes called a visual display unit) is an electronic visual display for computers. Laser Printer: $150-$400 A laser printer is a common type of computer printer that rapidly produces high quality text and graphics on plain paper. Projector: $300-$3000 A video projector takes a video signal and projects the corresponding image on a projection screen using a lens system. Scanner: $100-$300 In computing, a scanner is a device that optically scans images, printed text, handwriting, or an object, and converts it to a digital image.