PC & LAN MAINTENANCE TRAINING TRAINERS TRAINING ON COMPUTER MAINTENANCE AND TROUBLE SHOOTING.

PC & LAN MAINTENANCE TRAINING

TRAINERS TRAINING ON COMPUTER MAINTENANCE AND TROUBLE SHOOTING


Seminar Workshop Objectives:

• Acquire better understanding on the different types of Operating System for the proper diagnosis and repair of computer problems.

• Enhance skill in installing different types of Application Software and in configuring different peripherals.

• Develop expertise in network and trouble shooting.


Computer Hardware and Peripherals


Motherboards

• Motherboards (also called mainboards) are actually a carryover from architecture used for years in mainframe computers. Various circuit cards performing various functions all plug into many similar sockets on a common circuit board. Each circuit card performs a unique function in the computer and gets its power from the socket.


• The Abit KT-7A supports Advanced Micro Devices (AMD) processors and has the KT-133A chipset. The card slots on the Abit KT-7A, from bottom to top in the image below, shows that ISA has one slot, PCI has six slots and AGP has one slot. A special fan cools the chipset.

MSI 694D Pro AR Dual Flip Chip Socket 370 motherboard


• A partial view of the TechRam S3ProM motherboard shows slots: From bottom to top, ISA has one slot, PCI has two slots, audio modem riser (AMR) has one slot, and AGP has one slot.

Abit KT-7A AMD Processor Motherboard


Data Bus Width

• Modern Pentium class motherboards have a data bus with 64 bits. That is the width of the data highway that goes in and out of the processor. The Pentium processors, however, do use 32-bit registers to handle 32-bit instructions.

• Bus speeds and widths have increased due to faster processors and the needs of multimedia applications.


Typical bus names and widths are:

• Industry Standard Architecture (ISA) - 8 or 16 bits

• Extended Industry Standard Architecture (EISA) - 8 or16 bits

• Microchannel Architecture (MCA) - 16 or 32 bits

• VESA Local Bus (VLB) - 32 bits • Peripheral Component Interconnect (PCI) -

32 or 64 bits • Accelerated Graphics Port (AGP ) - 32 bits


Microprocessors

• A microprocessor -- also known as a CPU or central processing unit -- is a complete computation engine that is fabricated on a single chip. The first microprocessor was the Intel 4004, introduced in 1971. The 4004 was not very powerful -- all it could do was add and subtract, and it could only do that 4 bits at a time. But it was amazing that everything was on one chip. Prior to the 4004, engineers built computers either from collections of chips or from discrete components (transistors wired one at a time). The 4004 powered one of the first portable electronic calculators.


Microprocessor Progression: Intel Name Date Transistors Microns Clock speed Data width MIPS

8080 1974 6,000 6 2 MHz 8 bits 0.64

8088 1979 29,000 3 5 MHz16 bits

8-bit bus0.33

80286 1982 134,000 1.5 6 MHz 16 bits 1

80386 1985 275,000 1.5 16 MHz 32 bits 5

80486 1989 1,200,000 1 25 MHz 32 bits 20

Pentium 1993 3,100,000 0.8 60 MHz32 bits

64-bit bus100

Pentium II 1997 7,500,000 0.35 233 MHz32 bits

64-bit bus~300

Pentium III 1999 9,500,000 0.25 450 MHz32 bits

64-bit bus~510

Pentium 4 2000 42,000,000 0.18 1.5 GHz32 bits

64-bit bus~1,700


Information about this table: • The date is the year that the processor was first

introduced. Many processors are re-introduced at higher clock speeds for many years after the original release date.

• Transistors is the number of transistors on the chip. You can see that the number of transistors on a single chip has risen steadily over the years.

• Microns is the width, in microns, of the smallest wire on the chip. For comparison, a human hair is 100 microns thick. As the feature size on the chip goes down, the number of transistors rises.

• Clock speed is the maximum rate that the chip can be clocked at. Clock speed will make more sense in the next section.


Information about this table: • Data Width is the width

of the ALU. An 8-bit ALU can add/subtract/multiply/etc. two 8-bit numbers, while a 32-bit ALU can manipulate 32-bit numbers. An 8-bit ALU would have to execute four instructions to add two 32-bit numbers, while a 32-bit ALU can do it in one instruction.

• MIPS stands for "millions of instructions per second" and is a rough measure of the performance of a CPU.


Computer Memory

• memory is technically any form of electronic storage, it is used most often to identify fast, temporary forms of storage. If your computer's CPU had to constantly access the hard drive to retrieve every piece of data it needs, it would operate very slowly. When the information is kept in memory, the CPU can access it much more quickly. Most forms of memory are intended to store data temporarily.

A Sony Flash Memory Stick


Types of Electronic Memory

• RAM• ROM • Cache • Dynamic RAM• Static RAM• Flash memory • Memory Sticks • Virtual memory • Video memory• BIOS

RAM memory modulesFrom the top: SIMM, DIMM and SODIMM


Memory Basics • The CPU accesses

memory according to a distinct hierarchy. Whether it comes from permanent storage (the hard drive) or input (the keyboard), most data goes in random access memory (RAM) first. The CPU then stores pieces of data it will need to access, often in a cache, and maintains certain special instructions in the register.


ROM

• Read-only memory (ROM), also known as firmware, is an integrated circuit programmed with specific data when it is manufactured. ROM chips are used not only in computers, but in most other electronic items as well.


ROM Types

• ROM • PROM • EPROM • EEPROM • Flash memory


ROM

• Similar to RAM, ROM chips contain a grid of columns and rows. But where the columns and rows intersect, ROM chips are fundamentally different from RAM chips. While RAM uses transistors to turn on or off access to a capacitor at each intersection, ROM uses a diode to connect the lines if the value is 1. If the value is 0, then the lines are not connected at all.


PROM

• Creating ROM chips totally from scratch is time-consuming and very expensive in small quantities. For this reason, mainly, developers created a type of ROM known as programmable read-only memory (PROM). Blank PROM chips can be bought inexpensively and coded by anyone with a special tool called a programmer.


EPROM

• Erasable programmable read-only memory (EPROM) addresses this issue. EPROM chips can be rewritten many times. Erasing an EPROM requires a special tool that emits a certain frequency of ultraviolet (UV) light. EPROMs are configured using an EPROM programmer that provides voltage at specified levels depending on the type of EPROM used.


EEPROMs and Flash Memory • Electrically erasable programmable read-only

memory (EEPROM) Though EPROMs are a big step up from PROMs in terms of reusability, they still require dedicated equipment and a labor-intensive process to remove and reinstall them each time a change is necessary. Also, changes cannot be made incrementally to an EPROM; the whole chip must be erased.

• Flash memory, a type of EEPROM that uses in-circuit wiring to erase by applying an electrical field to the entire chip or to predetermined sections of the chip called blocks. Flash memory works much faster than traditional EEPROMs because it writes data in chunks, usually 512 bytes in size, instead of 1 byte at a time.


RAM

• Random access memory (RAM) is the best known form of computer memory. RAM is considered "random access" because you can access any memory cell directly if you know the row and column that intersect at that cell.

• The opposite of RAM is serial access memory (SAM). SAM stores data as a series of memory cells that can only be accessed sequentially (like a cassette tape).


Common RAM Types• SRAM

Static random access memory uses multiple transistors, typically four to six, for each memory cell but doesn't have a capacitor in each cell. It is used primarily for cache.

• DRAMDynamic random access memory has memory cells with a paired transistor and capacitor requiring constant refreshing.

• FPMDRAMFast page mode dynamic random access memory was the original form of DRAM. It waits through the entire process of locating a bit of data by column and row and then reading the bit before it starts on the next bit. Maximum transfer rate to L2 cache is approximately 176 MBps.


• EDODRAMExtended data-out dynamic random access memory does not wait for all of the processing of the first bit before continuing to the next one. As soon as the address of the first bit is located, EDO DRAM begins looking for the next bit. It is about five percent faster than FPM. Maximum transfer rate to L2 cache is approximately 264 MBps.

• SDRAMSynchronous dynamic random access memory takes advantage of the burst mode concept to greatly improve performance. The idea is that most of the time the data needed by the CPU will be in sequence. SDRAM is about five percent faster than EDO RAM and is the most common form in desktops today. Maximum transfer rate to L2 cache is approximately 528 MBps.


• DDRSDRAMDouble data rate synchronous dynamic RAM is just like SDRAM except that is has higher bandwidth, meaning greater speed. Maximum transfer rate to L2 cache is approximately 1,064 MBps (for DDR SDRAM 133 MHZ).

• RDRAMRambus dynamic random access memory is a radical departure from the previous DRAM architecture. Designed by Rambus, RDRAM uses a Rambus in-line memory module (RIMM), which is similar in size and pin configuration to a standard DIMM. What makes RDRAM so different is its use of a special high-speed data bus called the Rambus channel. RDRAM memory chips work in parallel to achieve a data rate of 800 MHz, or 1,600 MBps.


• Credit Card MemoryCredit card memory is a proprietary self-contained DRAM memory module that plugs into a special slot for use in notebook computers.

• PCMCIA Memory CardAnother self-contained DRAM module for notebooks, cards of this type are not proprietary and should work with any notebook computer whose system bus matches the memory card's configuration.


• CMOSRAMCMOS RAM is a term for the small amount of memory used by your computer and some other devices to remember things like hard disk settings. This memory uses a small battery to provide it with the power it needs to maintain the memory contents.

• VRAMVideoRAM, also known as multiport dynamic random access memory (MPDRAM), is a type of RAM used specifically for video adapters or 3-D accelerators. The "multiport" part comes from the fact that VRAM normally has two independent access ports instead of one, allowing the CPU and graphics processor to access the RAM simultaneously. VRAM is located on the graphics card and comes in a variety of formats, many of which are proprietary. The amount of VRAM is a determining factor in the resolution and color depth of the display.


IDE Controllers

• Integrated Drive Electronics (IDE) interface. Essentially, an IDE interface is a standard way for a storage device to connect to a computer. IDE is actually not the true technical name for the interface standard. The original name, AT Attachment (ATA), signified that the interface was initially developed for the IBM AT computer.

A close-up of the primary and secondary IDE interfaces

on a motherboard


Cable Key

• IDE devices use a ribbon cable to connect to each other. Ribbon cables have all of the wires laid flat next to each other instead of bunched or wrapped together in a bundle. IDE ribbon cables have either 40 or 80 wires. There is a connector at each end of the cable and another one about two-thirds of the distance from the motherboard connector.


USB Ports

• Just about any computer that you buy today comes with one or more Universal Serial Bus connectors on the back. These USB connectors let you attach everything from mice to printers to your computer quickly and easily. The operating system supports USB as well, so the installation of the device drivers is quick and easy, too.


Sample List of USB Devices

• Printers • Scanners • Mice• Joysticks• Digital cameras• Webcams• Modems• Speakers • Telephones • Network connections The rectangular socket is a typical

USB socket on the back of a PC


The USB standard uses "A" and "B" connectors to avoid confusion:

• "A" connectors head "upstream" toward the computer.

• "B" connectors head "downstream" and connect to individual devices.


Serial Ports

• Considered to be one of the most basic external connections to a computer, the serial port has been an integral part of most computers.

• Serial ports provide a standard connector and protocol to let you attach devices, such as modems, to your computer.


The Serial Connection


9-pin connector: 1. Carrier Detect - Determines if the modem is connected to a

working phone line. 2. Receive Data - Computer receives information sent from the

modem. 3. Transmit Data - Computer sends information to the modem. 4. Data Terminal Ready - Computer tells the modem that it is ready

to talk. 5. Signal Ground - Pin is grounded. 6. Data Set Ready - Modem tells the computer that it is ready to

talk. 7. Request To Send - Computer asks the modem if it can send

information. 8. Clear To Send - Modem tells the computer that it can send

information. 9. Ring Indicator - Once a call has been placed, computer

acknowledges signal (sent from modem) that a ring is detected.


25-pin connector: 1. Not Used 2. Transmit Data - Computer sends information to the

modem. 3. Receive Data - Computer receives information sent

from the modem. 4. Request To Send - Computer asks the modem if it

can send information. 5. Clear To Send - Modem tells the computer that it can

send information. 6. Data Set Ready - Modem tells the computer that it is

ready to talk. 7. Signal Ground - Pin is grounded.


8. Received Line Signal Detector - Determines if the modem is connected to a working phone line.

9. Not Used: Transmit Current Loop Return (+) 10. Not Used 11. Not Used: Transmit Current Loop Data (-) 12. Not Used 13. Not Used 14. Not Used 15. Not Used 16. Not Used 17. Not Used 18. Not Used: Receive Current Loop Data (+)

25-pin connector:


25-pin connector: 19. Not Used 20. Data Terminal Ready - Computer

tells the modem that it is ready to talk. 21. Not Used 22. Ring Indicator - Once a call has

been placed, computer acknowledges signal (sent from modem) that a ring is detected.

23. Not Used 24. Not Used 25. Not Used: Receive Current Loop

Return (-)

A dual serial port card


Parallel Ports

• Parallel ports were originally developed by IBM as a way to connect a printer to your PC. When IBM was in the process of designing the PC, the company wanted the computer to work with printers offered by Centronics, a top printer manufacturer at the time. A typical parallel port on the

back of your computer


Parallel ports can be used to connect a host of

popular computer peripherals: • Printers• Scanners• CD burners • External hard

drives • Iomega Zip

removable drives• Network

adapters


SCSI • Most home and small-office PCs use

an IDE hard drive and have a PCI bus for adding components to the computer. But a lot of computers, particularly high-end workstations and older Apple Macintoshes, use the Small Computer System Interface (SCSI) bus to connect components, which may include: – Hard drives– Scanners– CD-ROM/RW drives – Printers

SCSI devices usually connect to a controller card

like this one


Kinds of SCSI Connectors

Internal SCSI devices connect to a 50-pin ribbon cable

DB-25 SCSI connector



68-pin Alternative 3 SCSI connector

50-pin Centronics SCSI connector



Internal SCSI devices connect to a ribbon cable

External SCSI devices connect using thick, round cables


Peripheral Component Interconnect (PCI)

PCI cards use 47 pins

A typical PCI card


Hard Disks

• Hard disks were invented in the 1950s. They started as large disks up to 20 inches in diameter holding just a few megabytes. They were originally called "fixed disks" or "Winchesters" (a code name used for a popular IBM product).


Capacity and Performance

There are two ways to measure the performance of a hard disk:

• Data rate - The data rate is the number of bytes per second that the drive can deliver to the CPU. Rates between 5 and 40 megabytes per second are common.

• Seek time - The seek time is the amount of time between when the CPU requests a file and when the first byte of the file is sent to the CPU. Times between 10 and 20 milliseconds are common.

The other important parameter is the capacity of the drive, which is the number of bytes it can hold.


Inside: Electronics Board

• It is a sealed aluminum box with controller electronics attached to one side. The electronics control the read/write mechanism and the motor that spins the platters.


Inside: Beneath the Board

• Underneath the board are the connections for the motor that spins the platters, as well as a highly-filtered vent hole that lets internal and external air pressures equalize:


Inside: Platters and Heads

• In order to increase the amount of information the drive can store, most hard disks have multiple platters. This drive has three platters and six read/write heads:


Storing the Data • Data is stored on the surface of a

platter in sectors and tracks. Tracks are concentric circles, and sectors are pie-shaped wedges on a track

• A typical track is shown in yellow; a typical sector is shown in blue. A sector contains a fixed number of bytes -- for example, 256 or 512. Either at the drive or the operating system level, sectors are often grouped together into clusters.


Floppy Disk Drives

• The floppy disk drive (FDD) was the primary means of adding data to a computer until the CD-ROM drive became popular.

• Basically, a floppy disk drive reads and writes data to a small, circular piece of metal-coated plastic similar to audio cassette tape.


The major parts of a FDD include:

• Read/Write Heads

• Drive Motor

• Stepper Motor

• Mechanical Frame

• Circuit Board


PC Power Supplies

• In a personal computer (PC), the power supply is the metal box usually found in a corner of the case. The power supply is visible from the back of many systems because it contains the power-cord receptacle and the cooling fan.


Power Supply Wattage PC Item Watts

Accelerated Graphics Port (AGP) card 20 to 30W

Peripheral Component Interconnect (PCI) card 5W

small computer system interface (SCSI) PCI card 20 to 25W

floppy disk drive 5W

network interface card 4W

50X CD-ROM drive 10 to 25W

RAM 10W per 128M

5200 RPM Integrated Drive Electronics (IDE) hard disk drive 5 to 11W

7200 RPM IDE hard disk drive 5 to 15W

Motherboard (without CPU or RAM) 20 to 30W

550 MHz Pentium III 30W

733 MHz Pentium III 23.5W

300 MHz Celeron 18W

600 MHz Athlon 45W


Computer Mice

• A pointing device used to select various options.

This Microsoft Intellimouse uses optical technology


Inside a Mouse

• A ball inside the mouse touches the desktop and rolls when the mouse moves.

• Two rollers inside the mouse touch the ball. One of the rollers is oriented so that it detects motion in the X direction, and the other is oriented 90 degrees to the first roller so it detects motion in the Y direction. When the ball rotates, one or both of these rollers rotate as well.


Inside a Mouse

• The rollers each connect to a shaft, and the shaft spins a disk with holes in it. When a roller rolls, its shaft and disk spin.

• An on-board processor chip reads the pulses from the infrared sensors and turns them into binary data that the computer can understand.


Inside a Mouse

• On either side of the disk there is an infrared LED and an infrared sensor. The holes in the disk break the beam of light coming from the LED so that the infrared sensor sees pulses of light. The rate of the pulsing is directly related to the speed of the mouse and the distance it travels.


Data Interface

• Most mice in use today use the standard PS/2 type connector.

• These pins have the following functions

1. Unused 2. +5 volts (to power the chip and

LEDs) 3. Unused 4. Clock 5. Ground 6. Data

A typical PS/2 connector: Assume that pin 1 is located just to the left of the black

alignment pin, and the others are numbered

clockwise from there.


Computer Keyboards

• The part of the computer that we come into most contact with is probably the piece that we think about the least. But the keyboard is an amazing piece of technology.

An Apple Extended keyboard


Types of Keyboards

• 101-key Enhanced keyboard • 104-key Windows keyboard • 82-key Apple standard keyboard • 108-key Apple Extended keyboard


Inside the Keyboard

rubber dome

rubber dome switches

key matrix

microprocessor and controller circuitry of a keyboard


BIOS


BIOS

• One of the most common uses of Flash memory is for the basic input/output system of your computer, commonly known as the BIOS (pronounced "bye-ose"). On virtually every computer available, the BIOS makes sure all the other chips, hard drives, ports and CPU function together.

• The BIOS is special software that interfaces the major hardware components of your computer with the operating system. It is usually stored on a Flash memory chip on the motherboard, but sometimes the chip is another type of ROM.


What BIOS Does

• When you turn on your computer, the BIOS does several things. This is its usual sequence:

1. Check the CMOS Setup for custom settings 2. Load the interrupt handlers and device drivers 3. Initialize registers and power management 4. Perform the power-on self-test (POST) 5. Display system settings 6. Determine which devices are bootable 7. Initiate the bootstrap sequence


Configuring BIOS

• To enter the CMOS Setup, you must press a certain key or combination of keys during the initial startup sequence. Most systems use "Esc," "Del," "F1," "F2," "Ctrl-Esc" or "Ctrl-Alt-Esc" to enter setup.

• Once you have entered setup, you will see a set of text screens with a number of options.


Common options include:

• System Time/Date - Set the system time and date

• Boot Sequence - The order that BIOS will try to load the operating system

• Plug and Play - A standard for auto-detecting connected devices; should be set to "Yes" if your computer and operating system both support it

CMOS Setup


• Mouse/Keyboard - "Enable Num Lock," "Enable the Keyboard," "Auto-Detect Mouse"...

• Drive Configuration - Configure hard drives, CD-ROM and floppy drives

• Memory - Direct the BIOS to shadow to a specific memory address

• Security - Set a password for accessing the computer • Power Management - Select whether to use power

management, as well as set the amount of time for standby and suspend

• Exit - Save your changes, discard your changes or restore default settings

Common options include:


Preventive Maintenance


Preventive Maintenance

• Cleaning of Computer, Keyboard and Printer

• Cleaning of Pointing Device

• Taking care of Computer

• To take care of your CD’s


Cleaning of Computer, Keyboard and Printer• Turn off the computer

and unplug the power cord

• Use soft cloth moistened with water an gently wipe the exterior of the computer, keyboard and printer.


Cleaning of Pointing Device

• Open the circular cover underneath the mouse

• Take out the rubber ball and wipe it with a soft, damp cloth

• Put the ball and close the cover


Taking care of Computer

• Do not expose the computer to direct sunlight

• Do not subject the computer to magnetic fields

• Do not expose the computer to dust and dirt

• Never place the system on uneven surfaces


To take care of your CD’s

• Keep your disc in its case when not in use to avoid scratches or other damage.

• When cleaning disc, use a clean, dust free cloth and wipe in a straight line from the center to the edge.

• Clean your CD drive periodically.


Troubleshooting


Troubleshooting

• No Display

• No Power

• Boot-up Problem

• Keyboard Problem

• Mouse Problem

• Floppy Disk Drive Problem

• Printing Problem


No Display

Check cable connections

Try restarting the computer

Test the computer with other monitor


No Power Check AC output voltage Check power cable connections Check the computer power supply


Boot-up Problem

Check CMOS configuration

Remove any disk inserted in the floppy drive


Keyboard Problem

• Reseat connections

• Replace with other keyboard

• Try re-starting


Mouse Problem

• Reseat connection

• Replace with other mouse

• Try restarting


Floppy Disk Drive Problem

• Check CMOS configuration

• Try using another set of diskette

• Clean drive with Disk Cleaner


Printing Problems

• Check printer power

• Check cable connections

• Check ink cartridge

• Replace printer cable


For Technical Assistance

You may contact,Mr. Pete D. Rabago

Ayala Foundation, Inc.10/F BPI Main Bldg

Ayala Avenue cor Paseo de Roxas, Makati CityOr call (632)752-1187

e-mail : [email protected]@ayalafoundation.org


Operating System


Operating Systems • The operating system

defines our computing experience. It's the first software we see when we turn on the computer, and the last software we see when the computer is turned off.

• It's the software that enables all the programs we use.


At the simplest level, an operating system does two things:

• It manages the hardware and software resources of the computer system. These resources include such things as the processor, memory, disk space, etc.

• It provides a stable, consistent way for applications to deal with the hardware without having to know all the details of the hardware.


The operating system's tasks, in the most general sense, fall into six

categories:

• Processor management • Memory management • Device management • Storage management • Application interface • User interface


Hardware Configuration


AGP

• Accelerated Graphics Port AGP and AGP graphics cards are now the standard for processing graphics on computers. Like all hardware, the technology and specifications are constantly improving.


Computer Monitors

• An output device that displays information.

• Often referred to as a monitor when packaged in a separate case, the display is the most-used output device on a computer. The display provides instant feedback by showing you text and graphic images as you work or play.


number of colors different bit depths

Bit-Depth Number of Colors

12

(monochrome)

24

(CGA)

416

(EGA)

8256

(VGA)

1665,536

(High Color, XGA)

2416,777,216

(True Color, SVGA)

3216,777,216

(True Color + Alpha Channel)

Sony flat-panel display


Sound Cards

• The voice in your computer that lets you know when you've received a new e-mail is made possible by the sound card. Before the arrival of sound cards, personal computers (PCs) were limited to beeps from a tiny speaker on the motherboard.

• In 1989, Creative Labs introduced the Creative Labs SoundBlaster® card.

Industry Standard Architecture16-bit sound card


Anatomy of a Sound Card

• A typical sound card has: – a digital signal processor

(DSP) that handles most computations

– a digital to analog converter (DAC) for audio leaving the computer

– an analog-to-digital converter (ADC) for audio coming into the computer


– read-only memory (ROM) or Flash memory for storing data

– musical instrument digital interface (MIDI) for connecting to external music equipment (for many cards, the game port is also used to connect an external MIDI adapter)

– jacks for connecting speakers and microphones, as well as line in and line out

– a game port for connecting a joystick or gamepad

Anatomy of a Sound Card


Sound cards may be connected to: • headphones • amplified speakers• an analog input source

– microphone– radio– tape deck– CD player

• a digital input source – digital audiotape (DAT) – CD-ROM drive

• an analog output device - tape deck • a digital output device

– DAT – CD recordable (CD-R)


Modems

• The word "modem" is a contraction of the words modulator-demodulator. A modem is typically used to send digital data over a phone line.


Modem Speeds

• 300 bps - 1960s through 1983 or so • 1200 bps - Gained popularity in 1984 and 1985 • 2400 bps • 9600 bps - First appeared in late 1990 and early 1991 • 19.2 kilobits per second (Kbps) • 28.8 Kbps • 33.6 Kbps • 56 Kbps - Became the standard in 1998 • ADSL, with theoretical maximum of up to 8 megabits per

second (Mbps) - Gained popularity in 1999


CD Burners

• An external writable CD drive, also called a CD burner: With this type of drive, you can take music or data files from your computer and make your own CDs.

• Today, writable CD drives (CD burners) are standard equipment in new PCs, and more and more audio enthusiasts are adding separate CD burners to their stereo systems.


Laser Assembly

• The CD burner has a moving laser assembly, just like an ordinary CD player. But in addition to the standard "read laser," it has a "write laser." The write laser is more powerful than the read laser, so it interacts with the disc differently.

The laser assembly inside a CD burner


Scanners

• Scanners have become an important part of the home office over the last few years. Scanner technology is everywhere and used in many ways: – Flatbed scanners – Sheet-fed scanners – Handheld scanners – Drum scanners


Parts of a typical flatbed scanner include:

• Charge-coupled device (CCD) array

• Mirrors • Scan head • Glass plate • Lamp • Lens • Cover • Filters • Stepper motor

• Stabilizer bar • Belt • Power supply • Interface port(s) • Control circuitry


There are three common connections used by scanners:

• Parallel • Small Computer

System Interface (SCSI)

• Universal Serial Bus (USB)


Digital Cameras

• The digital camera is one of the most remarkable instances of this shift because it is so truly different from its predecessor.

• All digital cameras have a built-in computer, and all of them record images in an entirely electronic form.


Some typical resolutions that you find in digital cameras

• 256x256 pixels • 640x480 pixels • 1216x912

pixels • 1600x1200

pixels

Image Size TIFF(uncompressed)

JPEG(high quality)

JPEG(medium quality)

640x480 1.0 MB 300 KB 90 KB

800x600 1.5 MB 500 KB 130 KB

1024x768 2.5 MB 800 KB 200 KB

1600x1200 6.0 MB 1.7 MB 420 KB

Image Capacity


number of storage systems currently used in digital cameras

• Built-in memory - Some extremely inexpensive cameras have built-in Flash memory.

• SmartMedia cards - SmartMedia cards are small Flash memory modules.

• CompactFlash - CompactFlash cards are another form of Flash memory, similar to but slightly larger than SmartMedia cards.

• Memory Stick - Memory Stick is a proprietary form of Flash memory used by Sony.

• Floppy disk - Some cameras store images directly onto floppy disks.

• Hard disk - Some higher-end cameras use small built-in hard disks, or PCMCIA hard-disk cards, for image storage.

• Writeable CD and DVD - Some of the newest cameras are using writeable CD and DVD drives to store images.


Inkjet Printers

• An inkjet printer is any printer that places extremely small droplets of ink onto paper to create an image.


Impact vs. Non-impact • There are several major printer

technologies available. These technologies can be broken down into two main categories with several types in each: – Impact - These printers have a

mechanism that touches the paper in order to create an image.

– Non-impact - These printers do not touch the paper when creating an image.


There are two main impact technologies:

– Dot matrix printers use a series of small pins to strike a ribbon coated with ink, causing the ink to transfer to the paper at the point of impact.

– Character printers are basically computerized typewriters. They have a ball or series of bars with actual characters (letters and numbers) embossed on the surface.


Non-impact technologies:

• Laser printers, covered in-depth in use dry ink (toner), static electricity, and heat to place and bond the ink onto the paper.

• Inkjet printers, which are described in this article, use a series of nozzles to spray drops of ink directly on the paper.

• Solid ink printers contain sticks of wax-like ink that are melted and applied to the paper.

• Dye-sublimation printers have a long roll of transparent film that resembles sheets of red-, blue-, yellow- and gray-colored cellophane stuck together end to end.


• Thermal wax printers are something of a hybrid of dye-sublimation and solid ink technologies. They use a ribbon with alternating CMYK color bands.

• Thermal autochrome printers have the color in the paper instead of in the printer. There are three layers (cyan, magenta and yellow) in the paper, and each layer is activated by the application of a specific amount of heat.

Non-impact technologies:


Inside an Inkjet Printer

1. Print head assembly – Print head – Ink cartridges – Print head stepper motor – Belt – Stabilizer bar


2. Paper feed assembly – Paper tray/feeder – Rollers – Paper feed

stepper motor



3. Power supply

4. Control circuitry

5. Interface port(s)



Application Software Installation


Application Software Installation

• MS – Office 97

• MS – Office 2000

• MS – Office XP


Directory CommandDirectory Command

REN CommandREN Command

DEL CommandDEL Command

EDIT CommandEDIT CommandDIR CommandDIR Command

COPY CommandCOPY Command

Format CommandFormat Command

PATH CommandPATH Command

ATTRIB CommandATTRIB Command

CHKDSK CommandCHKDSK Command


Format CommandFormat Command

a. C:> FORMAT A:b. C:> FORMAT A:/Sc. C:> FORMAT A:/Vd. C:> FORMAT A:/S/V/Q

Prepares a diskette for use or wipesout all data from the disk.


DIR CommandDIR CommandDisplays the contents of a diskor a directory.

a.C:> DIRb.C:> DIR / Pc. C:> DIR / Wd.C:> DIR / P / We.C:> DIR / Bf. C:> DIR / L


COPY CommandCOPY Command Copies a file or a group of filesfrom one disk to another or fromone directory to another.

Syntax: C:> COPY <source> <destination>


REN CommandREN Command Renames file or a group of files.

Syntax: C:> REN <old filename> <new filename>


DEL CommandDEL Command Deletes or erases a file or agroup of files from disk or a directory.

C:> DEL <filename>


Directory CommandDirectory Command

MD –creates a directoryCD –changes current / working directoryRD –removes a directoryCD\ - makes root directory as the current directoryCD. –change to current directoryCD.. –change to parent directory


EDIT CommandEDIT Command

Ctrl

Ctrl

Home

End


PATH CommandPATH Command Sets the path for the commandand files.

a.To display the current pathC:>\ PATH

b. To set the pathC:>\ PATH =C:>\<dirname1>; C:\<dirname2>


ATTRIB CommandATTRIB Command Display or changes the attributesof a file or group of files.

a. To display the attributes of a fileC:>\attrib <filename>

b. To unprotect a file in DOSC:>\attrib –r a:<filename>

c. To make a file hiddenC:>\attrib +h a:<filename>

d. To remove the hidden attribute of a fileC:>\attrib –h a:<filename>


CHKDSK CommandCHKDSK Command Display the contents of a disk, including hidden files; displaysalso the status of a disk.

a.To display only the status of a diskC:>\CHKDSK A:>

b. To display the status and the contents of disk including the files

C:>\CHKDSK A:/V


Network Concept


Local Area Network (LAN)

• An Ethernet card, on the other hand, connects directly to the computer's bus. Ethernet cards come in two flavors: one that accepts 10 Mbps, and another that accepts 100 Mbps.


Why Network?

• Networking allows one computer to send information to and receive information from another. Certainly the Internet is the most conspicuous example of computer networking, linking millions of computers around the world, but smaller networks play a roll in information access on a daily basis.


Local Area vs. Wide Area

• Local area network (LAN) technologies connect many devices that are relatively close to each other, usually in the same building. The library terminals that display book information would connect over a local area network.

• Wide area network (WAN) technologies connect a smaller number of devices that can be many kilometers apart.


The Ethernet

• In 1973, at Xerox Corporation’s Palo Alto Research Center (more commonly known as PARC), researcher Bob Metcalfe designed and tested the first Ethernet network. While working on a way to link Xerox’s "Alto" computer to a printer, Metcalfe developed the physical method of cabling that connected devices on the Ethernet as well as the standards that governed communication on the cable.


Ethernet Basics

• Ethernet is a local area technology, with networks traditionally operating within a single building, connecting devices in close proximity.

• Ethernet devices could have only a few hundred meters of cable between them, making it impractical to connect geographically dispersed locations.

• Modern advancements have increased these distances considerably, allowing Ethernet networks to span tens of kilometers.


Ethernet Terminology

Medium - Ethernet devices attach to a common medium that provides a path along which the electronic signals will travel. Historically, this medium has been coaxial copper cable, but today it is more commonly a twisted pair or fiber optic cabling.


• Segment - We refer to a single shared medium as an Ethernet segment.

• Node - Devices that attach to that segment are stations or nodes.

• Frame - The nodes communicate in short messages called frames, which are variably sized chunks of information.

Ethernet Terminology


Ethernet Medium


Bridges

• To alleviate problems with segmentation, Ethernet networks implemented bridges. Bridges connect two or more network segments, increasing the network diameter as a repeater does, but bridges also help regulate traffic.


Switched Ethernet

• Modern Ethernet implementations often look nothing like their historical counterparts. Where long runs of coaxial cable provided attachments for multiple stations in legacy Ethernet, modern Ethernet networks use twisted pair wiring or fiber optics to connect stations in a radial pattern.


Alternative Network Technologies: Token Ring

• The most common local area network alternative to Ethernet is a network technology developed by IBM, called token ring. Where Ethernet relies on the random gaps between transmissions to regulate access to the medium, token ring implements a strict, orderly access method.


Token Ring


LAN Switches

• Switches are a fundamental part of most networks. They make it possible for several users to send information over a network at the same time without slowing each other down.

Illustration of a Cisco Catalyst switch


Networking Basics


Network Topologies

Bus network topology


Network Topologies

Ring network topology


Network Topologies

Star network topology


Network Topologies

A typical star bus network


Fully Switched Networks

An example of a network using a switch


Thank You…

PC & LAN MAINTENANCE TRAINING TRAINERS TRAINING ON COMPUTER MAINTENANCE AND TROUBLE SHOOTING.

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Transcript of PC & LAN MAINTENANCE TRAINING TRAINERS TRAINING ON COMPUTER MAINTENANCE AND TROUBLE SHOOTING.