Class 3 Presentation

Computer Hardware and Fault Finding – Class 3 ● ● ● ● ● ● ● ● ● ● ●

Operating Systems What Do Operating Systems Do? Wakeup Call (Boot process) File Systems, Partitioning, Formatting Your BIOS settings Contents of CD Basic DOS commands Install Windows 98SE (Second Edition) Network Setup (protocols, workgroup, IP address) Ping test Connecting to shared folder

Operating Systems ●

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Any desktop or laptop PC that you buy normally comes preloaded with Windows XP. Macintosh computers come preloaded with OS X. Many corporate servers use the Linux or UNIX operating systems. The operating system (OS) is the first thing loaded onto the computer -- without the operating system, a computer is useless. More recently, operating systems have started to pop up in smaller computers as well (i.e from cell phones to wireless access points). The computer in a typical modern cell phone is now more powerful than a desktop computer from 20 years ago. The purpose of an operating system is to organize and control hardware and software so that the device it lives in behaves in a flexible but predictable way.

The Bare Bones ●

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Not all computers have operating systems. The computer that controls the microwave oven in your kitchen, for example, doesn't need an operating system. It has one set of tasks to perform, very straightforward input to expect (a numbered keypad and a few pre-set buttons) and simple, never-changing hardware to control. For other devices, an operating system creates the ability to: * serve a variety of purposes * interact with users in more complicated ways * keep up with needs that change over time

The Bare Bones... ●

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All desktop computers have operating systems. The most common are the Windows family of operating systems developed by Microsoft, the Macintosh operating systems developed by Apple and the UNIX family of operating systems developed by many different organizations. There are hundreds of other operating systems available for special-purpose applications, including specializations for mainframes, robotics, manufacturing, real-time control systems and so on.

What Do Operating Systems Do? ●

At the simplest level, an operating system does two things: 1. It manages the hardware and software resources of the system. In a desktop computer, these resources include such things as the processor, memory, disk space, etc. (On a cell phone, they include the keypad, the screen, the address book, the phone dialer, the battery and the network connection.) 2. It provides a stable, consistent way for applications to deal with the hardware without having to know all the details of the hardware (i.e when MS Word sends a print job to the printer)

What Do Operating Systems Do?.. ●

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The first task, managing the hardware and software resources, is very important, as various programs and input methods compete for the attention of the central processing unit (CPU) and demand memory, storage and input/output (I/O) bandwidth for their own purposes. In this capacity, the operating system plays the role of the good parent, making sure that each application gets the necessary resources while playing nicely with all the other applications, as well as husbanding the limited capacity of the system to the greatest good of all the users and applications.

What Do Operating Systems Do...? ●

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The second task, providing a consistent application interface, is especially important if there is to be more than one of a particular type of computer using the operating system, or if the hardware making up the computer is ever open to change. A consistent application program interface (API) allows a software developer to write an application on one computer and have a high level of confidence that it will run on another computer of the same type, even if the amount of memory or the quantity of storage is different on the two machines.

What Do Operating Systems Do...? ●

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Even if a particular computer is unique, an operating system can ensure that applications continue to run when hardware upgrades and updates occur. This is because the operating system and not the application is charged with managing the hardware and the distribution of its resources. One of the challenges facing developers is keeping their operating systems flexible enough to run hardware from the thousands of vendors manufacturing computer equipment. Today's systems can accommodate thousands of different printers, disk drives and special peripherals in any possible combination.

Wakeup Call (Boot Process) ●

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When you turn on the power to a computer, the first program that runs is usually a set of instructions kept in the computer's read-only memory (ROM). This code examines the system hardware to make sure everything is functioning properly. This power-on self test (POST) checks the CPU, memory, and basic input-output systems (BIOS) for errors and stores the result in a special memory location. Once the POST has successfully completed, the software loaded in ROM (sometimes called the BIOS or firmware) will begin to activate the computer's disk drives.

Wakeup Call (Boot Process)... ●

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The bootstrap loader is a small program that has a single function: It loads the operating system into memory and allows it to begin operation. In the most basic form, the bootstrap loader sets up the small driver programs that interface with and control the various hardware subsystems of the computer. Then it turns control of the computer over to the operating system.

File Systems ●

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Every computer we use today almost always has a hard drive. Hard Drives store information on little platters, which are shaped like Frisbees, but made of metal and coated with a magnetic substance. But how exactly is the data organized on those little platters? They do it with a thing called a file system. File systems are mostly operating system dependent. This means that almost every operating system has a different type of file system. Windows is the most widely used operating system in the world. The Dos/Windows file system is called File Allocation Table, or just FAT for short.

File Systems... ●

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NTFS (NT File system) is also another type of file system used by Microsoft's Windows NT, 2000 and XP. (Each of these also support the FAT file system). NTFS has features to improve reliability, such as transaction logs to help recover from disk failures. To control access to files, you can set permissions for directories and/or individual files. NTFS files are not accessible from other OSs such as DOS

Partitioning ●

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Partitioning is one of the necessary steps to prepare a drive for use. It is the process of defining certain areas of the hard disk for the operating system to use as a volume. A volume is a section of the drive with a letter, like C: or D:. All hard drives must be partitioned, even if they will have only one partition called C: A partition program writes a master partition boot sector to cylinder 0, head 0, sector 1. The data in this sector defines the start and end locations of each of the other partitions. It also indicates which of these partitions is active, or bootable, thus telling the computer where to look for the operating system.

Partitioning ●

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All systems can handle 24 partitions, either spread out on the same drive or many drives. This means that one can have up to 24 different hard drives, according to DOS. DOS can't recognize more than 24 partitions, although some other OSes may. The limiting factor is simply the availability of letters. All partitions must have a letter. There are 26 letters, A: and B: are reserved for floppy drives, leaving 24 letters available. Although there are third party partitioning programs that boast added capabilities, DOS FDISK is the accepted program for partitioning. FDISK sets up the partition in a way optimum for DOS, and allow more than one OS to operate on one system.

How To Partition ●

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The first partition is your primary DOS partition. This is your C: drive and can't be divided. This is also called the active partition. You can only have one active partition. The second partition is optional. It is called an extended partition. This is the space left over after the primary partition. Each extended partition must be labeled with a letter D: through Z:. In FDISK, there is one extended partition, with it being divided up into Logical DOS Drives which each have a drive letter. To start this, type "fdisk" at the A> prompt. If this doesn't work, it is because your drive is not installed correctly.

How To Partition... ●

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First you have to setup a primary DOS partition. Choose Option 1 ( Create DOS partition or Logical DOS drive). Choose Option 1 in the next menu. Now you can make your entire C: drive the primary partition or only a part of it. Many people just make the entire drive one partition just to stay simple. If you want to break from this norm, specify the amount of drive you want to partition in either megabytes or percentage of total drive. Next, you'll need to make this partition active. Return to the main FDISK menu and choose Option 2 ( Set Active Partition). Follow the prompts.

Formatting ●

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Formatting is another necessary step to hard drive preparation, and very simple. In most cases, when installing a new hard drive, all you need to do is a high-level format. It is usually the final step in preparation and must be done after partitioning. When preparing a new drive, use the "FORMAT C: /S" command, entered at a command prompt. This high-level formats the volume C:. The "/s" command switch tells the FORMAT program to copy hidden opertating system files to the volume.

Formatting... ●

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After confirming that you do indeed mean to format your drive (it will warn you about data loss), you will need to wait for several minutes while the drive is formatted. It will then prompt you for a label. You can type a label if you wish, or just hit ENTER to skip it. Formatting marks bad sectors as unreadable, writes the boot sector, creates the FAT, writes the root directory, and copies system files.