HARD DISK DRIVE (HDD)

Jazz

STORAGE DEVICES One of the widely used Hardware for

Storing Permanent Data is HARD DISK DRIVE

It is used for Storing of DATA for long term use.

Hard Disk Drive Introduction

Hard Disk Drive is a nonvolatile data storage device, it means that the storage device retains the data even when no power is supplied to the computer.

Some of the profound changes in PC hard disk storage are its capacity, data transfer rates from the media.

Topic 4 - Hard drive Interface Integrated Drive Electronics (IDE)/EIDE

It is used to attach Mass Storage media devices to the computer.

The next generations of IDE interface is Enhanced IDE (EIDE)

Small Computer System Interface (SCSI) It is capable of supporting up to 7 to 15 devices.

Serial ATA (SATA) It is an internal or inside-the-box interface technology. External SATA is commonly known as ESATA.

USB It is an External , pocket Harddisk

Topic 1 - Features Storage Capacity

The storage capacity of the hard disk refers to the amount of disk space that can be used to store the user data.

Data Transfer Speed There are two ways to measure the speed of the disk drive

Average seek time

Transfer rate

Stability It has been measured by Mean Time Between Failure (MTBF).

TYPES OF HDD

HDD

PATA/IDE(PARALLEL ADVANCE

TECHNOLOGYATTACHMENT)

SATA(PARALLEL ADVANCE

TECHNOLOGYATTACHMENT)

USB/EXTERNALHARD DISK

Hard Drive Controllers

IDE (aka parallel ATA) EIDE SCSI SATA

IDE HARD DISK DRIVE

IDE Hard Disk is a 40 Pin Connector Hard Disk and is Connected to IDE connector on Motherboard

Motherboard Connections

Onboard Controllers(2 x 40 pin male ports)

Primary IDE controller is usually faster – ATA/66, 100

or 133. Secondary controlleroperates at ATA/33

Normally, the IDE controllersIdentified as IDE1 and IDE2

on the motherboard

INTERNAL PARTS OF THE HDD

INTERNAL PARTS… PLATTER SPINDLE MOTOR HEAD ACTUATOR ACTUATOR READ/WRITE HEAD LOGIC BOARD CONNECTOR POWER SUPPLY CONNECTOR OUTCASING BOX

Topic 3 - Hard Disk Drive Components

A flat, round disk called platters is used in a hard disk

The platters are loaded on a spindle.

Spindle motor spins the platters. Electromagnetic read/write

devices called heads are mounted onto sliders.

Each platter has two heads

Topic 3 - Hard Disk Drive Components

Platters

This platter is made up of substrate material, which gives structure and rigidity

Platters are physically connected in the middle and driven by the spindle motor.

Hard Disk Read/Write Heads

The hard disk drive read/write heads act like an interface between the magnetic media and the part of the hard disk.

Heads are joined to the head actuator move across the disk.

Topic 3 - Hard Disk Drive Components

Types of Read or Write Heads Ferrite Head – It is used for magnetic recording. Metal in Gap Head (MIG) - A metal substance has been

filled in the gap, and increases the resistance of magnetic saturation.

Thin Film Head - This head floats closer to the disk than the other heads.

Magneto Resistive Head - The MR head can change resistance.

Topic 3 - Hard Disk Drive Components

Giant Magneto Resistive Head (GMR) - It will work on multilayer of materials dumped in it.

Head Actuator Mechanism Stepper motor actuators It is an electrical motor that

can step from location to other, with click-stop positions

Voice Coil Actuator It is used to shift the head

arms in and out . It has a special guidance

system

Topic 3 - Hard Disk Drive Components

Spindle Assemble The spindle motors are directly connected to the hard disk platter spindle

Spindle Motor The motor that spins the platters is called the spindle motor.

Logic Board (s) The logic boards have electronics that control the drive’s spindle and head actuator systems.

PLATTER

PLATTER IS A METALIC PLATE WHICH IS USED TO STORE THE DATA IN THE ELECTROMAGNETIC FORM.

THE DATA IS SAVED IN TRACK,SECTOR & CLUSTER FORMAT

THERE CAN BE MORE THAN ONE PLATTER IN A HARD DISK

SPINDLE MOTOR SPINDLE MOTOR is used to revolve

the Platter to access the each and every part of the HARD DISK

The revolving of the platter is measured in RPM (RPM stands for REVOLUTION PER MIN/ROTATIONS PER MIN)

Current RPM ranges from 7,200 to 15,000

ACTUATOR

ACTUATOR is used to make access the Read Write Head to the every corner of the Platter

If we consider the live example for the Actuator, it is like a CAR WIPER which moves in 45 degree approximately

READ AND WRITE HEAD

Read Write Head often refereed as R/WHEAD

It is a Small Black Device which is responsible for the Operation of Reading and Writing.

It is used for Reading and Writing operations from the HARD DISK

READ AND WRITE PROCESS

Platters are divided into 512 byte sectors. These sectors are the area on the platter that data is written to. The platters have a magnetic coating applied to them that is extremely sensitive to magnetism.

LOGIC BOARD

IT is a Circuit Board which is used to send the signals and logical operations related to HARD DISK

WORKING

While the platters are rotating in a circle, the read/write heads are moved over the disk surface to the location where they need to write (or save) information. The read/write heads do not actually touch the surface of the disk platters; instead, they “hover” about ten micro-inches (or millionths of an inch) above—that’s not even enough space to place a hair between the read/write head and the platter’s surface. This design helps improve disk performance, because a read/write head that made contact with the platter would cause friction, slowing down the rotation speed of the disk.

Hard Drive Controller

Hard DriveController

External Data Bus

In IDE hard drives, the contoller circuitry is built into the drive

The controller allows the hard drive to send/receive data using the external data bus

THE STORAGE MEATHOD

THE DATA IS STORED IN THE FORM OF TRACKS SECTOR AND CLUSTERS

TRACKS

Just as there are grooves, or tracks, on a record or music CD, there are also tracks on each platter. These tracks are evenly spaced across the platter’s surface.

SECTORS

The platter is divided into pie slices, thus dividing the tracks into 512-byte sectors. Sectors are the actual storage areas for data, and each has an address that is made up of the platter side number, the track number, and the sector number on that track.

SECTOR

CLUSTERS

A group of any number of sectors can make up a cluster. When a partition is formatted, the file system will determine the cluster size based off the partition size. For example, a partition that is 2GB in size formatted as FAT will use a 32K-cluster size. That same 2GB partition formatted as FAT32 will use only a 4K-cluster size.

Topic 2 - Geometry of Hard Drive

Cylinders

It is a set of all platters. Heads

It is used to read data from the hard disk drive’s disk platters

Sectors per Track

A track is a one ring of data on

single side

Tracks are divided into many

sectors. Write pre-compensation

Used to adjust the smaller tracks

Topic 2 - Geometry of Hard Drive

Landing-Zone

When the system is turned off, the BIOS should send the

heads of hard disk to the cylinder where there is no data.

Modes

Three methods available for data addressing

CHS (Cylinder Head Sector)

LBA (Logical Block Address)

ECHS (Extended Cylinder Head Sector)

MOUNTING A DRIVE IN CABINET

Connecting an IDE drive

40-pin IDE ribbon cableRed line aligned with pin 1

4 prong Molex Connector

IDE Cables

Ribbon Rounded No twist! 40 pin 40 pin/80 wires

Max speed = 33Mb/sec

Max speed = 133Mb/sec

40 wire IDE ribbon cable33 Mb/sec max

80 wire IDE ribbon cable133Mb/sec max

SATA Cable

7 pin connector

4-wire data cable

Motherboard SATA socket

BASIC CONNECTION

IDE1 and IDE2 at Startup

PATA Design

Primary IDE Channel

Secondary IDE Channel

Master Slave Master Slave

Max of 133 Mb/sec Max of 133 Mb/sec

SATA Design

SATA Controller

Drive 4

Drive 1

Drive 2

Drive 3

150 Mb/sec

150 Mb/sec

150 Mb/sec

150 Mb/sec

MASTER/SLAVE SETTINGS

MASTER/SLAVE

Configuring a Hard Disk

1. Connect data cable and power cable2. Power up PC, enter BIOS3. Standard CMOS settings4. Auto detect or enter CHS values5. Create partitions6. Format each drive7. Install O.S.

Hard Drive Partitioning

What is it? Primary Partition Extended Partition Logical Drives

Partitions

Primary Partition

Drive Letter = c:

Set to “Active”

Stores O.S.

Extended Partition

LogicalDrive 1

LogicalDrive 2

Primary Partition

Hard Disk

Drive Letter = d:

Drive Letter = e:

A+ Partition Facts

A maximum of 4 primary partitions per disk

Up to 24 logical drives per disk Each partition must be formatted A PC must have at least 1 primary

partition The primary partition is where the O.S. is

stored Extra partitions are optional

Disk Management

Topic 9- File System The file system decides the manner in which data is

accurately arranged on a hard disk drive.

The main function of the FAT is to give the mapping between clusters and the physical location of data in terms of cylinders, tracks, and sectors.

FAT 12

FAT 16

FAT 32

NTFS

Windows File Systems File System is created when you

format the drive. The types areFAT 16FAT 32NTFS

Formatting also creates the boot record, the root directory, the File Allocation Table and the data area

FAT 16 File Allocation Table 16-bit A max of 216 = 65,536 addressable

sectors Max partition capacity of 65,536 x 512 =

33Mb Does not support disks larger than 2.1

Gb Used up to Win95 release 1 1.44 Mb floppy disks, zip disks and USB

memory sticks are formatted using FAT

FAT 32

File Allocation Table 32 bit A max of 232 = 4 billion addressable sectors Grouped 4 512 byte sectors together = a

cluster 1 cluster = 2048 bytes or 2Kb Max hard disk size = 2 Tb Max partition size of (4 billion x 512 bytes) =

32Gb Allows for up to 24 logical drives Windows 95 release 2 onwards No mechanism for file security

NTFS

New Technology File System 64 bit file system Windows NT, 2000, XP Main Advantage = Security

(encryption) Supports partition sizes up to 2048

Gb or 2Tb

Topic 5 - Data Organization in Hard Disk

The data is recorded on the magnetic tracks of a

hard disk drive.

Each track is divided into number of sectors.

Data is pressed on each sector.

Microcomputers’ hard disk drives are following the

soft sector format.

In the latest soft sector format, the track number,

head number and sector number is written on

each sector’s ID field.

Topic 6 - Data Read and Write Operation

Hard disk heads convert electrical signals to magnetic signals and magnetic signals to electrical signals.

By using encoding method, the stored data has been recorded onto the hard disk.

This encoding method translates zeros and ones into patterns of magnetic flux reversals.

Topic 7 - Hard Disk Drive Configuration

Cable (Data and Power)

Power Cable

Interface Cable

Jumper Settings (Master/ Slave/ Cable Select)

They are sets of pins with caps placed in various arrangements.

In some drives manufacturers have cryptic MS, SL, CS initials

BIOS settings The BIOS made after 1996 will support a drive larger than 4GB.

Topic 7 - Hard Disk Drive Configuration

IO Address Devices use memory location for interfacing with the computer. A typical hard disk controller uses 1F0-1F7h I/O port.

Interrupt Request Line (IRQ)

It permits a hardware device to look inside the computer.

When the device need attention, IRQ makes direct line to the

microprocessor

DMA Channel

Without CPU interference, the DMA controller transfers data

from a drive to the computer’s memory.

Topic 8 - Hard Disk Drive Setup Low level formatting

The disk’s tracks are divided into a specific number of sectors.

LLF is most important for the proper operation of the drive.

Partitioning The hard disk drive can support separate file systems by

creating a partition on a hard disk drive.

High level formatting

The operating system marks the structures essential for

managing files .

High-level formatting is the creation of a table of contents for

the disk

Topic 8 - Hard Disk Drive Setup FDISK For example: 4 gig hard drives, divided it into 4

partitions. The four independent drives are ‘C’, ‘D’, ‘E’, and ‘F’.

'C' partition = 2 Giga Bytes 'D' partition = 1 Giga Bytes 'E' partition = 500MB 'F' partition = 500MB

Topic 10 - Sector Organization Cluster

Grouping sectors into larger blocks are called clusters .

Master Boot Record (MBR) The location of the master boot record is cylinder 0,

head 0, and sector 1. DOS Boot Record (DBR)

In the beginning of the boot drive the DOS boot record will load .

Boot Sector The two tasks of boot sector is to load in the

operating system and to inform the user information about the disk.

Topic 10 - Sector Organization File Allocation Table

The FAT has entry for each cluster, which describes how the file has been used, and which files are free for use.

Root Directory FAT file system uses root directory to format disk.

Data Area The content of the files are stored in data area.

Topic 11- Common Errors & Troubleshooting