CHAPTER 6 FLOPPY DISK DRIVE

Introduction :
	The floppy is an external storage device. It is a magnetic round disk enclosed in a plastic jacket. The data is stored on the magnetic surface of the floppy disk. You can transfer data from one computer to another using a floppy disk. The floppy disk drive reads and writes data to a floppy disk.
6.1 History of Floppy
	Alan Shugart created the floppy disk drive in the year 1967. The floppy disk for this floppy disk drive was 8 inches in size. This floppy could store data on one side and the floppy disk drive could only read the data from the floppy. The capacity of this floppy was about 100 KB. The floppy disk drive was upgraded to read and also write to floppy disks. The capacity of the floppy disk also increased to hold 250 KB.
	8 Inch Floppy Disk
	The size of the floppy disk was reduced to 5.25 inches. This disk was similar to the 8 inch disk and could store 160 KB of data. The 5.25 inch floppy was modified to store data on both sides of the disk. This increased the storage capacity of the floppy disk to 360 KB. The floppy disks were of low density. The density of the floppy specifies how the data is stored on the floppy. The more the density of the floppy disk the closer the data is stored and this increases the amount of data that the floppy disk can hold. The 5.25 inch floppy disk was enhanced and the density of the floppy disk was increased. The double-sided high-density floppy disk holds 1.2 MB of data. The 5.25 inch floppy disk has a Write Protect notch. Covering this notch using a tape or piece of paper protects the data on the floppy disk by making it only available for reading. This floppy disk has an Index hole that enables the floppy disk drive to identify the starting sector of the floppy disk. The write access part of the floppy disk enables the floppy disk drive head to read from and write data to the floppy disk.
	5.25 Inch Floppy Disk
	The size of the floppy disk decreased and reduced to 3.5 inches. The thickness of the floppy jacket was increased. Floppy disks of different sizes ranging from 2 to 4 inches were created to compete with the 3.5 inch floppy disk. The 3.5 inch floppy disk was standardized by the industry. The 3.5 inch floppy had a high density and could hold 720 KB of data. The floppy disk was then improved and the density increased to create a high-density floppy disk that could hold 1.44 MB of data. The 3.5 inch floppy disk was then improved and the double-sided floppy disk was created that could store data on both sides of the floppy disk.
	3.5 Inch Floppy Disk
	The 3.5 inch floppy disk has two holes at the bottom of the disk. One enables the floppy disk drive to identify if the floppy disk has a low density or high density. The other is a write protect switch of the floppy disk. This switch enables us to protect the data on the floppy disk from being accidentally modified or erased. Sliding the switch down makes the floppy disk read only. You must 131 slide the switch upward to enable data to be read and written to the floppy disk.
6.2 Types of Floppy Disk Drives
	Floppy disk drives are available in different sizes. The floppy disk drive shares the name with the size of the floppy disk that it uses. For example, the floppy disk drive that uses the 3.5 inch floppy disk is called the 3.5 inch floppy disk drive.
	6.2.1 5.25 Inch Floppy Disk Drive
	Older systems used the 5.25 inch floppy disk drive to read and write data to the 5.25 inch floppy disk. This drive has a lever on the front of the drive that must be turned clockwise, to lock the floppy disk in after inserting the disk in the drive. You must turn the lever anti-clockwise before removing the floppy disk from the drive
	6.2.2 3.5 Inch Floppy Disk Drive
	The 3.5 inch floppy disk drive can read and write data to the 3.5 inch floppy disk. The 3.5 inch floppy
	3.5 Inch Floppy Disk Drive
	The 3.5 inch floppy drives spins the floppy disk at a speed of 300 rotations per minute. This enables the floppy to be formatted with 80 tracks on each side of the disk. Each track is divided into 18 sectors. The sector can hold 512 bytes. The 3.5 inch floppy disk drive also has an eject button that is used to remove the floppy disk from the drive.
6.3 Components of the Floppy Disk Drive
	The floppy disk drive consists of different parts. These parts interact with each other and perform the functions of reading and writing data on the floppy disk. It is important to know the different components of the floppy disk drive before servicing the drive, and to understand the working of the floppy disk drive.
	6.3.1 Read Write Head
	The floppy disk drive has a read write head. This part performs the work of reading and writing data on the floppy disk by converting the binary signals to electro magnetic signals. The double-sided floppy disk drive has two heads on both the sides of the floppy disk drive to read and write data on both sides of the floppy disk. The position of the read write head on both sides of the drive is such that they are not opposed to each other. This positioning prevents any interruption between the heads while writing data on the floppy disk. The floppy disk drive uses the same head to perform both the actions of reading data and writing data on the floppy disk. The floppy disk head consists of two parts. The first part reads and writes data on the floppy disk. The second part is a set of two heads that erases the data from a track before the read write head writes the data on the track.
	6.3.2 Head Actuator
	The Head Actuator allows the read write head to access all the tracks on one side of the floppy. The head actuator moves the read write head forward, from the center of the floppy outwards, and backward to place the head over the required track. The head actuator is connected to a motor that moves the head forward and backward. This motor is the stepper motor.
	6.3.3 Spindle Motor
	The Spindle Motor spins the floppy disk in the floppy disk drive. The spindle motor has a clamp that catches the floppy disk when the floppy disk enters the floppy disk drive. The spindle motor rotates at a speed of 300 rotations per minute. 133
	6.3.4 Circuit Board
	The Circuit Board connects all the parts of the floppy disk drive together. It consists of the circuits that sends the data signals to the different parts of the floppy disk drive. The function used to run the floppy disk drive is built into the circuit board. It controls the speed of the motors and manages the position of the read write head over the required track.
	6.3.5 FDD Controller
	The Floppy Disk Drive (FDD) controller forms the interface between the floppy disk drive and the system. It is a card that controls the floppy disk drive. The FDD controller has pins and is affixed on the motherboard.
	6.3.6 Faceplate
	The Faceplate is also referred to as the bezel. The floppy disk is inserted in the floppy disk drive through the front plastic window. The faceplate has the same size or is larger than the floppy disk drive. The floppy disk drive that has a faceplate larger than the cabinet panel mounts from the outside of the cabinet. The faceplate that has a size equal to the cabinet panel can mount from both the inside as well as the outside of the cabinet. It is recommended to mount the floppy disk drive to the cabinet from the outside of the cabinet.
	6.3.7 Connectors
	The power supply connector supplies power to the floppy disk drive. The 3.5 inch floppy disk drive uses a small sized connector called the mini plug. The 5.25 inch floppy disk drive uses the larger connector.
	6.3.8 Cables
	The data cable connects the floppy disk drive to the motherboard. The 3.5 inch floppy disk drive uses the 34 pin data cable connector. The cable comes with a special twist that enables the system to assign the floppy disk drive as drive A or drive B.
6.4 Working of the Floppy Disk Drive
	The floppy disk drive reads data from a floppy disk just as a cassette player reads music from a cassette. The magnetic particles on the surface of the floppy disk hold the stored data. The head moves over these magnetic particles and reads the data. The data is stored in the sectors and tracks of the floppy disk. The tracks are concentric circles on the floppy disk.
	Sectors and Tracks
	The steps followed by the floppy disk drive to read data from the floppy disk: The user executes a command, or the program requests information from the floppy disk. The spindle motor in the floppy disk drive rotates the floppy disk. The stepper motor moves the read write head over the required track and the read write head reads the data from the floppy disk. The floppy disk drive sends the data to the microprocessor for processing. The spindle motor stops rotating the floppy disk in the floppy disk drive. The steps followed by the floppy disk drive to write data on the floppy disk: 135 The user executes a command, or the program sends data to be written on the floppy disk. The spindle motor in the floppy disk drive rotates the floppy disk. The stepper motor moves the read write head over the required track for the read write head to read the track address from the floppy disk for storing the data. The erase coils located on the read write head erases the data from the track. The write head is energized. The write head converts the binary data into electromagnetic impulses and writes the data on the floppy disk. The spindle motor stops rotating the floppy disk in the floppy disk drive.
6.5 Installing the Floppy Disk Drive
	You must install the floppy disk drive to the motherboard to make it accessible to the system. To connect the floppy disk drive we require the floppy disk drive and the connecting cable.
	Best practices
	1. Turn off the power supply and unplug all external devices connected to the system. 2. Check the front panel of the system case to check if there is a vacant slot to install the floppy disk drive. 3. Check the data cable if you can attach additional devices to it. 4. Check if there is a spare power supply cable to connect to the floppy disk drive.
	Precautions
	5. Wear an anti-static wristband. 6. Insert the connectors gently so as not to damage any hardware.
	Hands on exercise
	To install a floppy disk drive : 1. Open the system case. 2. Remove the plastic panel from the front of the system case. 3. Slide the floppy disk drive into the case opening from outside of the system case. 4. Attach screws to hold the floppy disk drive in place. 5. Connect the power cable to the floppy disk drive
	Attaching Power Cable to the Floppy Drive
	6. Connect one end of the data cable to the motherboard. 7. Connect the other end of the data cable to the floppy disk drive according to the drive letter that must be assigned to the floppy disk drive
	Attaching Data Cable to the Floppy Drive
	8. Close the system case.
6.6 Configuring the Floppy Disk Drive
	A system can have two floppy disk drives. The drives are represented using the A: and the B:. The floppy disk drive can be assigned the required drive letter using the data cable. For example if you want to assign the drive letter A to the 3.5-inch floppy disk drive, you must connect the floppy disk drive to the first connector of the cable. You can also specify the required drive letter A to the floppy disk drive by inverting the data cable before affixing it to the floppy disk drive, if the data cable does not have a twist in it. You must configure the system BIOS to detect the installed floppy disk drive.
	Hands on exercise
	To configure the floppy disk drive : 1. Start the system. 2. Press the Del key on the keyboard. The BIOS settings appear. 3. Select the Standard CMOS Settings. The screen displaying the CMOS settings appears. 4. Select the required floppy disk drive. 5. Modify the option to display the installed floppy disk drive. 6. Save and Exit the BIOS settings. _ The BIOS settings may differ from one motherboard to the other, you can refer to the motherboard manual to configure the floppy disk drive. 137
6.7 Formatting a Floppy Disk
	The floppy disk drive stores data on the floppy disk. You must format a floppy disk before using it for the first time. A new floppy disk is like a brand new empty cupboard that has no shelves in it. Formatting a floppy disk creates sectors and tracks on the floppy disk. It is like creating shelves in the new cupboard. The manufacturer usually formats the floppy disks before supplying them. An unformatted floppy must be formatted before use. You can also format a floppy disk that contains some data on it. Formatting wipes out all the data stored on the floppy disk.
	Hands on exercise
	To format a floppy disk : 1. Take the floppy disk. 2. Check the write protect notch to ensure that it is in the read write mode. 3. Insert the floppy disk in the floppy disk drive. 4. Double-click My Computer from the desktop. 5. Right-click the 3.5 inch floppy icon. The pop-up menu appears. 6. Select Format from the pop-up menu.
	Displaying My Computer Window
	5. Right-click the 3.5 inch floppy icon. The pop-up menu appears. 6. Select Format from the pop-up menu.
	Format Dialog Box
	The Format dialog box enables you to specify the settings for formatting a floppy disk. The dialog box displays the following: _ Capacity - Specifies the type of floppy disk to be formatted _ File system - Specifies the file system structure for the floppy disk _ Allocation unit size- Specifies the size for the sectors _ Volume label - Specifies the label name for the floppy disk _ Format options - Specifies additional formatting options _ Quick format - Performs a quick format by deleting files from the floppy _ Enable Compression - Compresses the data stored on the floppy _ Start - Starts the formatting _ Close- Closes the dialog box 139 7. Click Start to start formatting the floppy.
6.8 Aligning the Floppy Disk Drive
	The read write head of the floppy disk drive writes data on the floppy disk. This head writes the data on the tracks of the floppy disk.
	Writing Data on a Track
	The head of the floppy disk drive sometimes gets misaligned. Due to this, the head writes data on the floppy disk. The data is however not written on the track, but it is misaligned.
	Head Writing Data on a Track
	The floppy disk written in a drive with its head misaligned is readable only in the drive that writes the data on the floppy disk. Reading this floppy disk in another drive may display an error. The floppy disk written in any other drives may also not be readable in such a floppy disk drive with a misaligned head. You must use software such as Drive Probe that is distributed by Accurite. This software enables you to align the read write head of the floppy disk drive.
6.9 Creating a Bootable Floppy Disk
	The system running an operating system such as Windows 2000 requires certain files to start the system. These are the system files such as ntldr, ntdetect.com and boot.ini are located on the hard 140 disk. The system performs a boot sequence when the system starts that loads the system files from the hard disk into the memory and this enables the system to operate. Dangerous software programs such as viruses, accidental deletion of the system files, or hardware problems prevents the system from loading the system files during booting. This prevents us from using the system. A bootable floppy disk contains the important system files required to start the system. To use the bootable floppy disk we must insert the bootable floppy disk into the floppy disk drive and start the system. Ensure that the BIOS boot preference is set to locate the boot files from the floppy disk drive to enable the system to boot from the floppy disk.
	Hands on exercise
	To create a bootable floppy disk: 1. Format the floppy disk as shown above. Slide the write protect tab on the floppy disk to the read write mode. 2. Open My Computer after the format is complete. 3. Browse to the C:. 4. Select the system files ntldr, ntdetect.com and boot.ini, required to boot the system. 5. Select Edit _ Copy to copy the files. 6. Browse the floppy disk using My Computer. 7. Select Edit _ Paste to place the copied files on the floppy disk. 8. Remove the floppy disk from the floppy disk drive. 9. Slide the write protect tab on the floppy disk to the read only mode. Ensure that windows explorer is configured to display system and hidden files. In My Computer, use the Tools _ Folder Options and click the View tab to view hidden files.
6.10 Troubleshooting the Floppy Disk Drive
	The floppy disk drive may have some problems. These problems can damage the floppy disk and also damage important data stored on a floppy disk. You can troubleshoot the floppy disk drive to correct any errors that the floppy disk drive may have.
	6.10.1 Cannot Detect the Floppy Disk Drive
	The system cannot find the floppy disk drive and displays an error message. The causes for the floppy disk drive not being detected are that the floppy disk drive is not properly installed or configured, or there is some hardware conflict. 1. Check if the cable connecting the floppy disk drive to the motherboard is properly connected. 2. Check that the floppy disk drive is appropriately configured in the BIOS settings. 3. Unplug any new hardware installed as the hardware may conflict with the floppy disk drive. 4. The floppy disk drive may be defective.
	6.10.2 Unable to Read or Write Data on the Floppy Disk
	The floppy disk drive does not read the inserted floppy disk and displays an error message. The causes for the floppy disk drive not reading the floppy disk are that the floppy disk is corrupted or the floppy disk drive is bad. 1. Check if the write protect switch is in the read write mode if you cannot write data on the floppy disk. 2. Insert a different floppy disk in the floppy disk drive, if the floppy disk drive reads the floppy disk then the floppy disk must be corrupted. 3. Clean the head of the floppy disk drive using a head cleaning floppy. 4. Check that the floppy disk is formatted, if the floppy disk is a new. 5. Check if the read write head is misaligned.
	Summary :
	In this Chapter you learnt : _ The floppy disk is a magnetic round disk enclosed in a plastic jacket. _ The first floppy disks were 8 inches in size. _ The size of the floppy disk was reduced to 5.25 inches. These floppy disks were flexible. _ The 3.5 inch floppy disk was standardized by the industry. This floppy disk was available ina hard plastic jacket. _ The 3.5 inch floppy disk has a write protect switch to protect the stored data. _ The read write head of the floppy disk reads data from and writes data on the floppy disk. _ The double-sided floppy disk drive has two heads on both the sides of the floppy disk drive, to read and write data on both sides of the floppy disk. _ The head actuator moves the read write head forward and backward to access all the floppy disk tracks. _ The spindle motor spins the floppy disk in the floppy disk drive. _ The circuit board sends the data signals to the different parts of the floppy disk drive. _ The Floppy Disk Drive (FDD) controller forms the interface between the floppy disk drive and the system. _ The floppy disk is inserted in the floppy disk drive through the front plastic window called the faceplate. _ The data cable connects the floppy disk drive to the motherboard. _ The floppy disk drive must be installed for the system to access it. _ Configuring the floppy disk drive assigns it the required drive letter. _ Formatting a floppy disk creates sectors and tracks on the floppy disk. _ Floppy disk written in a drive with its head misaligned is readable only in the drive that writes the data on the floppy disk. _ The system requires important system file to start the system. _ The bootable floppy disk enables to boot a system when the system files on the hard disk cannot be accessed. _ Trouble shooting a floppy disk drive fixes the drive.
CHAPTER 8 CD-ROM AND CD WRITER DRIVES
	Chapter Objectives :
	At the end of the Chapter, you will be able to: _ Identify the types of CDs _ Identify the types of CD drives _ Examine the structure of the CD drive _ Install the CD drive _ Align the CD drive _ Work with CD Writing software _ Troubleshoot the CD drive
	Recall :
	In the previous Chapter you learnt that the hard disk is a primary and permanent storage device. The type and interface of the hard disk determines the speed and the reliability of the hard disk. The file system specifies the method used to store files and folders on the system. You can partition the hard disk and create drives on it. Formatting the hard disk creates sectors and tracks on the hard disk. 1. What are the different types of hard disks? 2. List the types of hard disk interfaces.
	You Have to Study Again
	3. What are the components of a hard disk? 4. Explain the types of hard disk formatting.
	Introduction :
	The data stored on the CD can last for many years. The CD can store large amounts of data and is used to distribute software, music, and movies. The CD drive reads the data stored on the CD. The CD-ROM drive can only read data from a CD. Today CD-R and CD-RW drives are available that can read, and also burn data on a CD.
8.1 Types of CDs
	Compact Disc (CD) is a removable storage media. The CD is a cheap and reliable media. The CD is a round disc with a hole in the center that stores data
	CD-ROM Disc
	The 3.5 inch floppy disk stores about 1.44 MB of data. This enabled users to only copy files of small size on the floppy disk. The CD stores more data than the floppy disk. The CD holds about 650 - 700 MB of data. The CD is made out of a clear piece of polycarbonate plastic. The CD has different layers that enable the CD drive to read data from the CD. The layers that make up the CD depend on the type, and the number of times that you can write data on the CD. The basic layers for the CD are : _ Polycarbonate plastic - Hard transparent plastic layer of the disc _ Aluminum - Reflects the laser beam from the CD drive like a mirror that reflects light _ Acrylic - Protects the CD layers _ Label - Enables you to name the CD for identification
	8.1.1 Audio Compact Disc
	The Audio CD is used to store music and has replaced the audio cassette. Regular use of the audio cassette reduces the song quality due the friction between the tape player head and the audio 174 cassette. The song quality on an Audio CD does not decrease like the audio cassette, because there is no friction between the CD player and the Audio CD. Therefore, the songs recorded on the Audio CD are of better quality and have a longer shelf life. An Audio CD can store about 74 minutes of music.
	8.1.2 CD Read-Only Memory (CD-ROM)
	The CD-ROM is used to store data for distributing software and other large files such as databases and word processors. The CD-ROM disc can also hold music and movie files. Files on a CD-ROM can only be read as the CD-ROM is stamped. In stamping, the data the CD data is written on a glass disc. This glass disc is used like a rubber stamp and is pressed on the CD-ROM and creates a permanent image of the data on the Polycarbonate plastic layer of the CD-ROM.
	8.1.3 Compact Disc-Recordable (CD-R)
	The CD-R disc is like a blank book that you can write in using a pen. The text once written cannot be erased. The CD-R is useful to backup data. The CD-R can also be used to create music CDs that can be played on music systems. The CD-R disc has a special layer between the polycarbonate plastic layer and the reflective aluminum layer to store the data on the CD-R disc. This layer is made up of a photosynthetic dye that is sensitive to strong light. When the dye is heated using a strong laser beam the dye darkens and becomes opaque. The area that is opaque does not reflect the laser beam back to the optical sensor, and is interpreted as the binary digit 0. The area on the disc that is not opaque reflects back the laser beam on the optical sensor and is interpreted as the binary digit 1.
	8.1.4 CD-ReWritable (CD-RW)
	You can write text in a book using a pencil. When you do not need the text, you can erase it from the book. The CD-RW disc enables you to rewrite data to the CD-RW disc. The data when not required can be erased from the CD-RW disc. Erasing the data from the CD-RW disc removes all the data from the CD-RW disc and makes the CD-RW disc empty for writing data to it. The CD-RW disc is useful for transferring data from one system to another, or for storing files that are updated regularly. The CD-RW has a special layer called, the phase change compound layer, that makes it possible to rewrite data to the CD-RW disc. The phase change compound is a special substance made up of silver, antimony, tellurium and indium. This substance is transparent in the solid state. When this substance is heated using a laser beam of high intensity, the substance melts to the liquid state and acts like a pit and does not allow the laser beam passing through it. Erasing the disc converts the phase change compound from the liquid back to the solid state.
8.2 Types of CD Drives
	The CD drive can be classified as the CD-ROM drive, the CD-R drive and the CD-RW drive. The CD-ROM drive reads data from a CD. The CD-R drive can read data from a CD and can also write data to a CD-R disc. The CD-RW drive can read, write and also rewrite data. _ The speed of the CD drive is specified using a number followed by the alphabet X.
	8.2.1 CD-ROM Drive
	The CD-ROM drive can read data from the CD-ROM disc and the Audio CD. You can use this drive to install software from a CD and play music from an Audio CD
	CD-ROM Drive
	The speed of the CD drive specifies the amount of data the CD drive reads from the CD in a second. This speed is called the transfer speed of the CD drive. The original speed of the CD drive is 150 KB per second. The speed of the CD drive is specified using a number followed by X. For example, if the speed of the CD drive is specified as 52X, then the CD drives reads data from the CD at a speed of 52X. The number specifying the speed of the CD drive must be multiplied with the original speed of 150 KB per second, to get the speed of the CD drive. For example if the speed of the CD drive is specified as 12X, then the transfer speed is 12 x 150 = 1,800 kbps.
	8.2.2 CD-R Drive
	The CD-R drive can read data from the CD-ROM, Audio CD, and the CD-R disc. The CD-R drive can also write data to the CD-R disc. This drive is useful for backing up data that must not be modified, on a CD-R disc. The CD-R drive can write to the CD-R disk in a single session or using multiple sessions. In the single session, the data is written to the CD-R disc and the connection is closed such that the CDR is finalized and no data can be further added to the CD-R disc. Using multiple sessions you can continue adding data to the CD-R disc until the disc is full. The speed of the CD-R drive is specified using two numbers, each number is followed by the alphabet X. The first number specifies the speed at which the CD drive reads data from the CD. The second number specifies the speed at which the CD-R drive writes data to the CD-R disc. For example, if the speed of the CD-R drive is 52X - 12X, then the CD-R drives reads data from the CD at a speed of 52X, and writes to the CD-R disc at a speed of 12X.
	8.2.3 CD-RW Drive
	The CD-RW drive enables you to read, write and also rewrite data to the CD-RW disc. This is useful for transferring data from one system to another, especially data files that are large in size such as video files. The speed of the CD-RW drive is specified using three numbers, each number is followed by X. The first number specifies the speed at which the CD-RW drive writes data to the CD. The second number specifies the speed at which the CD-RW drive rewrites data to the CD-RW disc. The third number specifies the speed at which the CD-RW drive reads data from the CD. For example, if the speed of the CD-RW drive is 48X - 12X - 52X, then the CD-RW drives writes data to the CD-R disc at a speed of 48X, writes data to the CD-RW disc at a speed of 12X, and reads data at a speed of 52X.
8.3 Structure of the CD Drive
	The CD drive consists of different parts that enable it to read data from the disc. The CD drive is a precision device because the timing of sending the laser beam and collecting the laser beam reflected from the CD must be precise. A misalignment in the structure or working of any part of the CD drive will result in an error in reading the data from the CD.
	8.3.1 Optical Head
	The optical head of the CD-ROM drive consists of a read laser and an optical sensor. The read laser targets a laser beam on the disc. The optical sensor collects the reflected laser beam from the disc. The optical head is a very delicate and expensive part of the CD-ROM drive. It is also a high precision part of the CD drive because any deviations in the alignment of the optical head, will not allow the CD drive to read the data from the disc properly. The CD Writer has two lasers, one for reading data from the CD and one laser for writing data on the CD. The strength of the write laser is very high.
	8.3.2 Head Actuator
	The head actuator moves the optical head forwards and backwards from the center of the CD to the outer end of the disc. This allows the optical head to access all the parts of the CD. The head actuator moves the optical head, away from the center of the CD, using very small intervals to follow the minute tracks on the CD.
	8.3.3 Spindle Motor
	The spindle motor catches the CD when it is inserted in the CD drive and spins it. The circumference of the CD at its center is less than the circumference at the outer edge. This means that more data is stored on the CD near the outer side than the inner side. The optical head covers more distance at the outer track of the CD-ROM disc. To enable the CD-ROM drive to read the data from the CD-ROM disc at a constant speed, the spindle motor reduces the spinning speed as the head actuator moves from the center outward.
	8.3.4 Loading Mechanism
	The loading mechanism specifies the method to load the CD in the CD drive. The frequently used method for loading the CD in the CD drive is the tray. The CD drive has an eject button that opens and closes the CD drive tray. The CD is placed on the CD drive tray after opening it. 177 CD drives also uses the caddy system to load the CD. The CD is inserted in a device known as a caddy. The caddy is a plastic case with a metal shutter. The caddy with the CD in it is inserted in the CD drive, just as a floppy disk is inserted in a floppy disk drive.
	8.3.5 Connectors
	The connector enables you to connect the CD drive to the system motherboard. The connectors are located at the back of the CD drive.
	Connectors
	The IDE cable connects the CD drive to the motherboard. The CD drive uses the 40 pin connector. You must ensure that the marking on the IDE cable is on the same side of the power supply cable when inserting it in the CD drive. The CD-ROM drive is also equipped with output connections for sound. You can connect the cable from here to the sound card or the sound output device.
	8.3.6 Jumpers
	Jumpers are switches on the hardware that enables you to change the hardware settings. The CD drive jumpers are located at the back of the CD drive. It enables you to set the CD drive as the master, or the slave. The master specifies that the hardware is set as the primary device and can control the other devices set as slave. You can also use the jumper to set the CD-ROM drive as the master or slave as per the cable selection using the IDE cable When you install two devices on the same cable one must be set as master and the other as slave. You must set the jumpers to cable select if you use a special cable to attach the devices to the motherboard. The special cables architecture sets one device to master and the other to slave.
8.4 Working of the CD Drive
	The CD-ROM drive has a laser beam that is a powerful ray of light. To read data from the CD, the CD-ROM drive flashes this laser on the CD. The laser beam passes through the transparent plastic layer of the CD and the reflecting aluminum reflects the laser beam back to the CD-ROM drive. This reflected laser beam falls on the optical sensor of the CD-ROM drive. The CD-ROM drive reads the light patterns formed according to the structure of the CD, and interprets the data stored on the CD. The CD Writer works in the same way as the CD-ROM drive for reading data from a CD. In addition to a read laser, the CD Writer also has a more powerful laser that is used to write data to the CD. The write laser modifies the CD-R disc to burn the data on the disc.
8.5 Installing the CD Drive
	Installing the CD drive connects the system and the CD drive. You must read the documentation supplied with the CD drive and the motherboard to check if the two are compatible. You may also have to configure the CD drive after installing it using the system BIOS.
	Best practice
	1. Write the details mentioned on the CD drive label such as the model number, and the serial number, in a safe place such as a diary. 2. Read the CD drive documentation thoroughly. 3. Check if there is a vacant slot available on the front panel of the system case to install the CD drive. 4. Check the motherboard to see if you can install another IDE cable, or if you must use the IDE cable connecting the hard disk to the motherboard. 5. If you are using the hard disk IDE cable, check if it can accommodate the CD drive. Note that you have to change the IDE cable if it has only one connector with one that has multiple connectors.
	Precautions
	Wear an anti-static wristband.
	Hands on exercise
	1. Adjust the jumper as required on the CD-ROM drive.
	Adjusting the Jumper
	2. Open the system case. 3. Remove a plastic panel from the front of the system case,
	Removing the Panel
	4. Insert the CD-ROM drive in the system case.
	Inserting the Drive in the System Case
	5. Attach screws to fix the CD-ROM drive in the system case.
	Attaching Screws to the CD-ROM
	6. Connect the Audio CD cable to the CD-ROM drive, if specified in the CD-ROM documentation.
	CD Audio Cable
	7. Connect the other end of the CD Audio Cable to the motherboard or the sound card, as specified in the CD-ROM documentation.
	IDE Connecting Cable
	8. Connect the IDE cable to the motherboard.
	Connecting the IDE Cable to the Motherboard
	9. Select the required connector on the IDE cable to set the CD-ROM drive as master or slave, if the CD-ROM drive jumper is set to cable select. 10. Connect the IDE cable connector to the CD-ROM drive.
	Connecting the IDE Cable
	11. Connect the 4-pin power adapter to the CD-ROM drive.
	Connecting the Power Adapter
	12. Close the system case. 13. Start the system. 14. Press the Delete key on the keyboard when the message to load the setup appears, the BIOS Setup Main menu page appears. Note that the Main menu page also displays the keys required to browse to the different options. 15. Browse to the Standard CMOS Setup option. 16. Press Enter to display the Standard CMOS setup screen. 17. Set the CD-ROM drive as the as the primary or secondary master/slave, as installed. 18. Press Esc to display the BIOS Setup Main menu page. 19. Save and Exit the BIOS Setup.
8.6 Aligning the CD Drive
	The CD drive may display errors while reading the CD from the CD drive. You must troubleshoot and check the CD drive thoroughly for defects. If the CD and all the parts of the CD drive are not defective, it may be possible that the head of the CD drive is misaligned. The alignment of the head can change after a lot of use, or due to dust particles or mechanical problems, the laser beam can miss the track and fall on the space between the two tracks. The misaligned head will not be able to read data accurately from the CD. This will leave the drive unusable. Realigning the head changes the setting of the head actuator, and re-focuses the laser beam back on the CD track. _ You must do this with extreme caution, only after the guarantee period of the CD drive has expired, and after you have tried all the other methods for troubleshooting the CD drive.
	Hands on exercise
	12. Close the system case. To align the CD drive head. 1. Open the system. 2. Remove the CD drive. 3. Unscrew and open up the CD drive. 4. Locate the screw to align the head.
	Head Alignment Screw
	5. Use a fine marker to mark the original alignment of the screw. 6. Use a screwdriver to turn the screw about 10 degrees clockwise or anti-clockwise. 7. Reassemble the CD drive. 8. Close the system. 9. Insert a CD in the CD drive and check if the CD drive reads data from the CD. 10. Repeat the above steps if the CD drive does not read the data from the CD.
8.7 Working with CD Writer Software
	The CD Writers comes with software that enables you to work with the CD Writer. You can download the required software from the Internet, from the CD Writer company website, or from websites such as www.download.com, and www.tucows.com. Using this software, you can write data to a CD-R, or the CD-RW. The task of writing to the CD involves heating the dye on CD, therefore this process is referred to as burning. CD writing software enables you to convert the files such as music files from one format to another before burning it on the CD.
	8.7.1 Ahead Nero
	Ahead Nero is a CD writing software that enables you to burn data from the system to the CD. Using this software, you can duplicate an existing CD. Nero also enables you to create a music CD or Video CD (VCD) that plays on compatible music systems and VCD players.
	8.7.2 Clone CD
	Clone CD is enables you to create a duplicate copy of a CD. This software first copies the image from the original CD. It then burns this image on the blank CD. The capacity of the empty CD must be equal to or greater than the original CD.
	8.7.3 Adensoft Audio/Data Burner
	Adensoft Audio/Data Burner software creates data backup on the CD. You can also create music CDs that can play on music systems.
8.8 Troubleshooting the CD Drive
	Troubleshooting CD drive techniques solve the problems that arise due to the improper functioning of the CD drive. The troubleshooting techniques for the CD drive can also solve the problems for the CD Writer.
	8.8.1 Cannot Detect the CD Drive
	The system cannot read data from the CD if the CD drive is not detected. When the CD drive is not detected, the drive letter does not appear in Windows Explorer. The system also displays error message while trying to read the CD from the MS-DOS prompt. The light on the CD drive also does not glow when a CD is inserted in the CD drive. Steps to correct this problem : 1. Check that the CD drive is appropriately configured in the BIOS settings. 2. Check if the cables connecting the CD drive to the motherboard are properly connected. 3. Check the cable supplying the power to the CD drive is properly connected. 4. Unplug any new hardware installed, to check if the hardware conflicts with the CD drive. 5. Check if the CD drive is defective by testing it on a different system.
	8.8.2 CD Drive Cannot Read the CD
	When the CD drive cannot read data from the CD inserted in the CD drive the system displays an error. This can cause the CD drive to skip tracks while playing music. You may also get errors while installing software or copying data from the CD to the system. 1. Check if the CD drive light glows when you insert the CD in the drive. If the light does not glow the system may not be detecting the CD drive. 2. Wash the CD using water. Wipe the CD using a dry cloth from the center towards the outer edge.
	Cleaning a CD
	3. Insert a different CD in the CD drive and try reading data from that CD. If it reads the data from the CD then the original CD may be dirty or corrupted. 4. Clean the head of the CD drive using a head cleaning CD. The head cleaning CD has a small brush that brushes the dust off the lens of the CD. You must place the head cleaning CD with the brush side down. 5. Realign the CD head.
	8.8.3 CD Writer Cannot Write Data to the CD-R / CD-RW
	Sometimes the CD Writer cannot write to the CD-R / CD-RW disc and the software used to write the CD displays an error and terminates the burn process. 1. Check if the disc has empty space for storing more data. 2. Use a different CD-R disc as the old one must be damaged or corrupted. 3. Unclose the disc session using the CD writing software, if it is closed. 4. Check if the source disc has a lot of scratches that prevents the drive from reading the data. 5. Clean the source disc. 6. Clean the CD drive using a head cleaning CD. 7. Reduce the writing speed of the CD writing software to match the speed of the CD.
	8.8.4 Creating a Bootable CD
	The system requires some important files for the user to work with the system. These files are located on the hard disk that has the operating system loaded on it. If these files are missing or corrupted, the system cannot load the files and you will not be able to work with the system. It is a good practice to keep a bootable CD handy. A bootable CD contains important files required to start the system, when the operating system does not load the files from the hard disk. You can use software such as Nero to create a bootable CD. You may need a bootable floppy disk to create the bootable CD using Nero. _ It is recommended to create and the bootable CD on a CD-RW disk and test it, before creating a permanent copy on a CD-R disk.
	8.8.5 Changing the Boot Sequence
	The system loads important system files located on the storage device connected to the system. When multiple devices are connected to the system, the system checks for required files from the connected devices in the order specified in the BIOS setup. The system loads the required files if they are located on the first device specified. If the required files are not found on the first device the system searches the files on the next device specified. You will have to change the boot sequence for installing the operating system or for booting into the system using the bootable CD. After changing the boot sequence, you must insert the bootable CD or the operating system installer CD in the CD drive when the system starts.
	Hands on exercise
	To set the sequence of the boot devices : 1. Start the system. 2. Press the Delete key on the keyboard when the message to load the setup appears, the BIOS Setup Main menu page appears. Note that the page displays the keys required to browse to the different options. 3. Browse to the Advanced Setup option. 4. Press Enter to display the Advances Setup screen. 5. Browse to the 1st Boot Device option. 6. Select the required device such as the CDROM. 7. Press Esc to display the BIOS Setup Main menu page. 8. Save and exit the BIOS Setup.
	Summary :
	In this Chapter you learnt : _ The CD is a round disc with a hole in the center that stores data. _ The CD holds about 650 - 700 MB of data. _ The Audio CD stores music. _ The CD-ROM disc is a stamped disc that is used for distributing software and other large files such as databases and word processors. _ The CD-R disc enables you to write data to the CD-R disc. The data written cannot be erased. _ The CD-RW disc enables you to rewrite data to the CD-RW disc. Erasing the data from the CDRW disc removes all the data from the CD-RW disc. _ The original transfer speed of data, of the CD drive, is 150 KB per second. _ The CD-R drive can also write data to the CD-R disc. _ The CD-RW drive enables you to read, write and also rewrite data to the CD-RW disc. _ The optical head of the CD-ROM drive consists of a read laser and an optical sensor. _ The CD Writer has two lasers, one for reading data from the CD and one laser for writing data on the CD. _ The head actuator moves the optical head forwards and backwards from the center of the CD to the outer end of the disc. _ The spindle motor spins the CD in the CD drive. _ The CD drive loads the CD in the drive using the tray or the caddy mechanism. _ Installing the CD drive allows the system to access the CD drive. _ Aligning the head actuator of the CD drive refocuses the laser beam on the CD track. _ Ahead Nero, Clone CD, and Adensoft Audio/Data Burner enables you to burn data to the CDR and CD-RW disc.
CHAPTER 9 DVD ROM AND COMBO DRIVES
	Chapter Objectives :
	At the end of the Chapter, you will be able to : _ List the types of DVDs _ Explain the structure of the DVD drive _ Explain the working of the DVD drive _ Identify the speed listings of DVD drives _ Install the DVD drive _ Configure the DVD drive _ Identify combo drives _ Troubleshoot the DVD drive
	Recall :
	In the previous Chapter you learnt that the CD drive is used to read data from the CD that is a removable storage media. The type of CD determines if you can read, write or rewrite data to a CD. The CD Writer allows you to write data on a CD-R and CD-RW using CD writing software. A bootable CD contains important system files required to boot the system. 1. What are the different types of CDs? 2. What are the different types of CD Drives?
	You Have to Study Again
	3. List the different components of a CD Drive. 4. Explain the steps to align a CD Drive.
	Introduction :
	Digital Versatile Disk or Digital Video Disk (DVD) is a form of digital storage. DVD is used to stores music, video, games, and multimedia applications. The DVD is similar to the CD in appearance and structure. The DVD offers higher capacity and better quality as compared to the CD. The DVD storage capacity is seven times that of a CD. To play a DVD, a DVD ROM drive is used. In addition, combo drives are available that play DVDs as well as CDs.
9.1 Types of DVD
	The data on a DVD is arranged in a spiral manner. The data on the DVD is recorded outwards from the center.
	Spiral tracks on a DVD
	Each data track on the DVD is made up of millions of data pits. These data pits are incredibly tiny and are measured in nanometers. These pits are seen as bumps by the laser that is used to read the data.
	The basic composition of the DVD is made up of :
	_ Polycarbonate plastic - Forms the plastic layers. The plastic layers are arranged to form a spiral track. This spiral track is extremely long and has data encoded in it in the form of microscopic pits. _ Thin reflective layer - Covers the plastic layers. The reflective layers cover the surface of the disk. The inner layer is formed of aluminum and the outer of gold. _ Lacquer - All the layers of plastic are joined together with lacquer. The disk is then cured in infrared light. This completes the creation of the DVD, which is about 1.2 millimeters thick. DVDs can hold information on a single side or both sides. Double-sided DVDs contain data on both sides of the disk. The different types of DVDs are: _ Single-sided single-layered DVD - Known as DVD-5, as it has a capacity of 4.7 GB. Data is stored in a single layer on one side of the DVD. The capacity of this type of DVD is more than seven times the capacity of the CD. _ Single-sided dual-layered - Has a capacity of 8.5 GB It is also known as DVD-9. Data is stored on two layers on one side of the DVD. In this type of DVD, the laser has to read data from both the layers. The size of the data pits is increased from a single-sided single-layered DVD. Since the pits are larger in size, the number of pits in the spiral tracks reduces. As a result, data storage cannot be achieved to the maximum. Therefore, the single-sided duallayered DVD does not have double the capacity of the single-sided single-layered DVD. _ Double-sided single-layered - Known as DVD-10 and has a capacity of 9.4 GB. Data is storedin a single layer on both sides of a DVD. This type of DVD has to be reversed manually to play both sides. Some DVD players perform automatic reversal of the DVDs. _ Double-sided dual-layered - Has a capacity of 17 GB. This is over 26 times the data capacity of an ordinary CD. It is also known as DVD-18. This type of CD is very costly and is rarely used. It provides eight hours of audio or video playback. There are different types of DVDs available for different applications. The different types of DVDs are:
	9.1.1 DVD-ROM
	The DVD-ROM disk stores data ranging from 4.7 GB to 17 GB. DVD-ROMs store films, computer software in a similar manner to CD-ROMs.
	9.1.2 DVD-Video
	The DVD-Video disk stores movies. In this type of DVD, crater-like structures on the surface of the DVD scatter the laser beam. This is different from the way the laser is reflected in ordinary DVDs. These types of DVDs require DVD drives with MPEG-2 decoder.
	9.1.3 DVD-Audio
	DVD-Audio stores high-quality music. These disks can also store video content and slide shows. DVD-Audio holds the surround sound version of the music.
	9.1.4 DVD-Recordable (DVD-R) and DVD plus Recordable (DVD+R )
	The DVD-R and DVD+R disks can be written only once. An organic dye coats a layer of these types of disks. When the disk is exposed to laser, it is permanently marked. The data is read in a DVD player. DVD+R stores data in many layers on the disk. As a result, DVD+R can store more data than DVD-R. Hence, it is expensive.
	9.1.5 DVD-RW and DVD+RW
	The DVD-RW and DVD+RW disks are known as phase-change disks. These types of disks use two different laser power levels to write and erase data. We can rewrite DVD-RW disks about a thousand times. It is possible to rewrite DVD+RW disks around ten thousand times.
	9.1.6 DVD-RAM
	The DVD-RAMs use phase change technology. It is possible to rewrite these disks 1,00,000 times. DVD-RAM disks have a capacity of 9.4 GB, with 4.7 GB on each side of the disk. We do not need DVD burners to write data on these DVDs. These DVDs can be accessed in the same manner as a hard drive or floppy disk.
	9.1.7 DVD-VR and DVD+VR
	DVD-VR and DVD+VR disks can be used for the creation of movies that can be edited. The content in these disks can be edited by adding or removing portions and changing the required parts. DVDVR disks cannot be played on ordinary home DVD players. The DVD player has to be DVD-RW compatible. DVD+VR disks can be played on home DVD players.
9.2 DVD ROM Drives
	DVD ROM drives read DVDs of different types. These drives are read-only drives and cannot write or record information on a DVD. The speed of the DVD ROM drive is indicated by a number followed by an x. The x indicates the basic speed of the DVD-ROM drive, which is 11.08 Megabits per second. You can measure the speed of the DVD-ROM drive by multiplying 11.08 Megabits per second with the number that indicates the speed of the drive. DVD-ROM drives can have two to three speeds listed. An example of a DVD ROM speed listing is 4x/24x. The first speed refers to the maximum speed at which data is read from a DVD. For this drive, the maximum speed at which data is read from a DVD will be 11.08 x 4 = 44.32 Megabits per second. The second speed listing refers to the maximum speed at which data is read from a CD. The optional third speed listing refers to the CD ripping speed. This is the maximum speed at which data is read from an audio CD for conversion to a digital format.
9.3 Structure of the DVD ROM Drive
	The front of the DVD ROM drive has a tray that accepts the DVD. It has the Eject button that opens the tray. The Eject button is also used to close the DVD tray. The DVD ROM drive has a manual eject button. This button is used in cases of emergency, like the tray not opening. The volume control is also located on the front of the DVD drive. There is a port for connection for the microphone. There 196 is also a light that indicates the status of the DVD drive.
	Front Panel of the DVD Drive
	The back panel of the DVD players has different ports for the connection of the DVD drive to the computer. There is a digital audio connector. The Audio connector is the port that is connected to the sound card or motherboard of the computer. The jumper connections configure the DVD drive as either master or slave.
	Back Panel of the DVD Drive
	The IDE connection connects the DVD drive to the motherboard of the computer. The IDE cable makes this connection. IDE stands for Integrated Drive Electronics. The IDE interface provides an interface for storage devices such as the DVD drive. This interface integrates the controller to the data drives of the computer. The controller is a chip that controls the transfer of data between the computer and the DVD drive. The Power-in connector connects the power adapter to the DVD drive. It is a 4-pin connector. The drive is set to master if it is the only drive connected to the computer. If a DVD drive is already connected to the computer, the drive will be set to slave. The jumper connections have various options. These options are: _ CS - Stands for Cable Select. This option is never used. It is a reserved option. _ SL - Stands for Slave. It connects the DVD drive as a slave device. This is the default option. _ MA - Stands for Master. It connects the DVD drive as a master device. This option is selected when the DVD drive is the only one connected to the IDE cable.
	Jumper Selection on the DVD Drive
	The DVD ROM drive plays DVDs and CDs. The main components of the DVD drive are: _ Motor - Spins the disk in the drive. The motor performs rotations that move the disk in the drive. _ Laser - Reads the data in the disk. _ Lens - Focuses the laser beam on the precise location in the disk. _ Tracking mechanism - Moves the laser beam with micron accuracy.
9.4 Working of the DVD Drive
	The tracking system of the DVD player consists of the tracking motor and the spindle motor. It is responsible for the proper alignment of the data tracks on the DVD and the laser beam. The spindle motor spins the DVD at a rate that allows for constant reading of data by the laser beam. The tracking motor moves the laser assembly to and from the center of the DVD. The DVD drive reads data from DVDs with the help of a laser assembly, which focuses a laser beam on the DVD. The laser beam reads the data on the DVD that is stored in the form of microscopic pits. The laser beam focuses on the reflecting layer of the DVD. In the case of the single-layered DVDs, the laser passes through the layer and to the reflective layer underneath it. If the DVD is duallayered, it has to focus on the inner reflective layer by passing through the two layers and then to the reflective layer. The laser is reflected off the reflective layer onto an electronic device. The DVD track has data encoded in it in the form of pits, and the areas on the track that do not contain data are flat and smooth. The laser is reflected in a different manner from the smooth area as compared to the pits of data. The electronic device studies the reflected signal for changes in reflection. The device then interprets the reflection changes and reads them as bits of data. The DVD drive has to convert the data read from the DVD into understandable bits. These bits of data are then sent to a DAC (Digital to Analog Converter) if the data is intended for a device that uses analog data. If the device is digital, the data can be directly passed to the device.
9.5 Installing and Configuring the DVD Drive
	Installation of the DVD drive enables the user to view DVDs and CDs. If the DVD drive is an R, RW, or RAM drive, the user can also record information, movies and music on the DVD.
	Best practices
	1. Read the instructional manual of the DVD drive thoroughly. 2. Note down the model number and the product number of the DVD drive. 3. Check the front of the system case to ensure that an empty bay can accommodate the DVD drive.
	Precautions
	Wear an anti-static wristband.
	Hands on exercise
	To install the DVD drive : 1. Write down the details of the DVD drive, such as the model number, and the serial number. 2. Read the instruction manual of the DVD drive thoroughly. 3. Wear an anti-static wristband. 4. Shut down the computer and turn off the power switch at the back of the computer. For additional safety, remove the power cable.
	Removal of the Power Cable
	5. Remove the system case covering.
	Removal of the System Case Cover
	6. Remove the drive cover on the front of the system case.
	Removal of the System Case Cover
	7. Set the DVD drive as either master or slave. This setting depends on whether the IDE cable for the drive is attached to a device already. If the IDE cable is not attached to any device, the setting will be master. In the other case, it will be slave. The jumpers on the DVD drive enable the setting of the drive.
	Setting of the jumpers on the DVD drive
	8. If the system case uses rails to fit the DVD drive, fix the rails on the drive.
	Fixing of the rails on the DVD drive
	9. Put the DVD drive into the gap.
	Insertion of the DVD drive in the gap
	10. Use screws to fix the drive to the system case if there are no rails.
	Connection of the DVD Drive to the Computer
	11. Attach the CD-Audio cable of the computer to the connector of the DVD drive.
	The Connection of the CD-Audio Cable to the DVD Drive
	12. Attach the other end of the cable to the sound card or the motherboard.
	The connection of the CD-Audio Cable to the Motherboard
	13. Plug the IDE cable to the motherboard, if the DVD drive is a master. If the DVD drive is a slave device, the IDE cable will be connected to the motherboard.
	Connection of the IDE Cable to the Motherboard
	14. Connect the drive connector of the IDE cable to the DVD drive.
	Connection of the IDE Cable to the DVD Drive
	15. Connect the power adapter to the drive.
	Connection of the Power Adapter to the DVD Drive
	16. Replace the system case of the computer. 17. Replace the power cord of the computer and turn the power on. 18. In most cases, the DVD drive is automatically installed and configured by the computer when the computer is turned on. If it is not configured automatically, follow the steps in the instruction manual and configure the DVD drive accordingly.
	Hands on exercise
	To configure the DVD drive using the system BIOS : 1. Start the computer. 2. Press the Del key during the boot sequence to display the BIOS main menu. 3. Select Standard CMOS Setup using the navigation buttons specified on the screen. 4. Press Enter to display the Standard CMOS setup screen. 5. Verify that the DVD drive is set as the as the primary or secondary master/slave. 6. Save and Exit the BIOS setup.
9.6 Combo Drives
	In the early days of DVD, it was only possible to view DVDs with the use of DVD drives. This caused a lot of inconvenience to people who had to replace their functional CD drives with new DVD drives. This problem gave rise to the need for a new type of drive that would combine the functionality of DVD drives and CD drives. A combo drive is a CD writer drive that can play DVDs. This type of drive can play back DVD and CD. It can also write data in CD-R and CD-RW disks.
9.7 Troubleshooting the DVD Drive
	A user can experience many problems with the DVD drive. You have to manage the DVD drive properly in order to avoid occurrence of problems. In case a problem occurs, troubleshooting the drive will help to a great extent. Troubleshooting the DVD drive is very important, as a faulty drive can lead to damage of DVDs. This can cause loss of large amounts of data from a DVD.
	9.7.1 DVD Does Not Play
	The DVD inserted in the DVD drive is not playing. There can be many reasons for this problem. The DVD disk may be corrupted or it is possible that the drive is damaged. 1. Check the DVD for scratches on the surface. Also check if it is clean. If the DVD is unclean, use a soft linen cloth to clean it. Do not use circular motions. Clean from the center outwards in a radial manner. 2. Play another DVD in the drive. If this DVD is playing fine, it is possible that the drive is dirty. In this case, clean the DVD drive with a cleaning disk for DVD players. If the drive still does not play the disk after being cleaned, the drive is faulty. 3. Check if the cables of the DVD drive are connected properly. 4. Check if the operating system is recognizing the DVD drive. Go to My Computer and check if the drive is recognized. If this detail is not shown in My Computer, access the BIOS to check that the operating system is recognizing the drive. 5. The computer may not be working properly. Check the power supply fan. Also, ensure that the processor is not overheated. 6. It is possible that the Windows registry is corrupt. The registry is the database that contains configuration information of the computer. You can use utilities like the PC Bug Doctor to repair the faults in the Windows registry. This software utility can be downloaded from the site http:/ /www.pcbugdoctor.com/download.html. 7. If the above steps do not work, contact the manufacturer of the DVD drive.
	9.7.2 There is no Power in an External DVD Drive
	1. If the drive is an external drive, check the power cord. It should be plugged properly to the socket. Ensure that the cord is connected properly to the DVD drive as well. 2. If the connections are proper, connect another device to the socket. If the other device is playing, it means that the socket is fine. 3. Unplug the power cord a few times. Then try playing the DVD player. If the player does not play, the cord or the drive itself is faulty.
	9.7.3 There is no Power in an Internal DVD Drive
	1. The internal DVD drives receive power from the computer power supply. If the other parts of the computer are problem-free, it means the power supply is not at fault. 2. Replace the connector of the DVD drive to the power supply to check if the problem is cause by the connector. If the DVD drive does not start working even after the connector is replaced, the drive is faulty.
	9.7.4 The Tray of the Internal DVD Drive Will Not Open
	1. Restart the Computer. Then try to open the tray. 2. If the tray does not open after restarting, check the BIOS settings to see if the computer recognizes the drive. 3. Try the manual eject button on the DVD drive. 4. Shut down and unplug the computer. Use a small device like a paperclip to insert in the pinhole on the front of the DVD drive. Try to open the tray a little with the help of the paperclip, and then open with your fingers.