Maxtor 300 manual What Else is Involved?, What is the Next Barrier?, Appendix a

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Breaking the 137GB Storage Barrier

A.1.5 What Else is Involved?

Effort is required from OS vendors to increase storage device addressing up to 48 bits or more. This increase will be a significant challenge for many OS vendors that have 32-bit code models. Adapting to 48-bit commands will be easy, but most vendors will stop filling data at the 32- bit boundary and pad the upper 16 bits with zeros, leaving that space empty.

The BIOS companies will also have to perform some work to recognize the increased capacity of the devices attached to the bus and allow the extended 48-bit commands to pass on to the devices. Boot partitions will also be an issue for the capacity of the drive if the BIOS does not recognize the 48-bit addressing scheme at or before the system boots the OS from the hard drive.

Independent software driver efforts for legacy operating systems (Windows NT 4, Windows 98, and so on) will need to be implemented to allow higher-capacity devices to work on installed systems and recognize the maximum available capacity of the drive over the 137-gigabyte limit.

A.1.6 What is the Next Barrier?

While it is true that the ATA/ATAPI-6 standard defines a method to provide a total capacity for a device of 144 petabytes, the next limit will be imposed not by the ATA devices but by many of the popular operating systems in use today. This limit will be at 2.2 terabytes (2,200 gigabytes). This barrier exists because many of today’s operating systems are based on 32-bit addressing. These operating systems include many flavors of Linux, Mac OS 9.x, and Windows 95, 98, ME, NT 4, 2000, and XP (Windows XP/64-bit also has the limit because of leveraged 32-bit code).

This barrier could be real as early as 2004 if current hard drive capacity rate increases continue along the same growth trends.

Appendix A:

Terminology

•BIOS: (an acronym for Basic Input/Output System design): The BIOS processes and redirects all data as it is being accessed and stored.

•FAT: (an acronym for File Allocation Table): The FAT tells the computer where data has been stored on the hard drive.

•CHS: (an acronym for Cylinders, Heads, and Sectors): The basic layout components of a hard drive. INT 13h & INT 13h extensions: protocols used for accessing data on hard drives.

A-4 Quickview 300 80/100/120/160/200/250/300GB PATA

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Contents MaxtorQuickview 80/100/120/160/200/250/300GB Pata Patents Publication Number Part Number Before You Begin McCarthy Blvd Milpitas, California Tel Fax General Description InstallationChapter Introduction ChapterProduct Specifications ATA BUS Interface and ATA CommandsService and Support Breaking the 137 Gigabyte Storage Barrier Appendix aList of Figures List of Tables Support Maxtor CorporationAudience ProductsTerminology and Conventions Manual OrganizationMSB References Product Overview KEY FeaturesGeneral Description Product EMI/EMS Qualifications Regulatory Compliance StandardsSpace Requirements InstallationUnpacking Instructions 2Quickview 300 20-Pack Shipping Container Hardware Options Pata Interface ConnectorCable Select CS Jumper 1AT Jumper OptionsDrive Select DS Jumper Master Jumper ConfigurationCylinder Limitation Jumper CLJ Power On Standby4AT Connector and Jumper Location Adapter Board Combination Connector J12.1 40-Pin Pata Bus Connector Pata BUS Adapter5J1 DC Power and Pata Bus Combination Connector DC Power J1, Section a Pata Bus Interface Connector J1, Section CExternal Drive Activity LED Mounting Orientation Installation For Systems With a Motherboard Pata Adapter Adapter Board InstallationClearance Ventilation8Drive Power Supply and Pata Bus Interface Cables Connecting the Adapter Board and the DriveOperating system limitations Techniques in Drive ConfigurationModels and Capacities Drive ConfigurationPerformance Specifications Parameter Value Physical DimensionsPower Requirements for 80/100/120/160/200GB Typical Power Requirements for 250GB/300GB TypicalVoltage Tolerance EPA Energy Star Compliance Power Mode DefinitionsAcoustic Noise1 Environmental Limits1Baseplate Tempurature Measurement Location Parameter Operating NON-OPERATING Shock and VibrationData Reliability Reliability SpecificationsAnnualized Return Rate Start/Stop CyclesCanadian Emissions Statement Safety Regulatory ComplianceElectrical Interface Signal Cable and ConnectorIntroduction Mechanical InterfaceCommand Feature Register Code Values Command InterfaceGeneral Feature Set Supported CommandsFlush Cache SET Multiple Mode 30h Write SectorsWord Content Description10-19 Serial number 20 Ascii characters 20-21 Retired Content Description Minimum PIO transfer cycle time without flow control Minor version number See Address Offset Reserved Area Boot, Incits TR272001 = release interrupt enabled Supported Content Description Reserved 255 Integrity word 15-8 Checksum Signature Product Support/Technical Assistance/Customer Service Service and SupportHistory Breaking the 137 Gigabyte Storage BarrierDOS Solving the 137 Gigabyte Capacity Barrier How is the Extension Implemented?What Do the Drives Need to Meet the Spec? What is the Next Barrier? What Else is Involved?Appendix a Appendix C Appendix B Big NumbersGlossary Glossary FCI Acronym for flux changes per inch. See also BPI Initialize See low level formatting Millisecond ms One thousandth of a second .001 sec Glossary Quickview 300 80/100/120/160/200/250/300GB Pata G-7 Glossary Index