Maxtor 5120 manual Reset and Interrupt Handling, Reset Handling

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HOST SOFTWARE INTERFACE

Reset and Interrupt Handling

Reset Handling

One of three different conditions may cause a reset: power on, hardware reset or software reset. All three cause the interface processor to initialize itself and the Task File registers of the interface. A reset also causes a set of the Busy bit in the Status register. The Busy bit does not clear until the reset clears and the drive completes initialization. Completion of a reset operation does not generate a host interrupt.

Task File registers are initialized as follows:

Error	1
Sector Count	1
Sector Number	1
Cylinder Low	0
Cylinder High	0
Drive/Head	0

Interrupt Handling

The drive requests data transfers to and from the host by asserting its IRQ 14 signal. This signal interrupts the host if enabled by bit 1 (IRQ enable) of the Fixed Disk Control register.

Clear this interrupt by reading the Status register, writing the Command register, or by executing a host hardware or software reset.

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Contents HA RD Drive Produc T MA Nual DiamondMax Plus 92048U8, 91792U7, 91536U6, 91280U5, 91024U4 and 90750U3Revisions Manual No Before You Begin U T I O NContents Product Specifications Handling and InstallationAT Interface Description Host Software InterfaceInterface Commands Service and SupportGlossary Figures Introduction Maxtor CorporationManual Organization AbbreviationsSignal Conventions ConventionsKey Words NumberingDiamondMax Plus 5120 Key Features Product DescriptionProduct Features Functional / InterfaceOn-the-Fly Hardware Error Correction Code ECC Logical Block AddressingDefect Management Zone DMZ Software ECC CorrectionRead-Ahead Mode Cache ManagementBuffer Segmentation Automatic Write Reallocation AWRMajor HDA Components Subsystem Configuration Jumper Location/ConfigurationCylinder Limitation Dual Drive SupportProduct Specifications Drive ConfigurationPerformance Specifications Models and CapacitiesPhysical Dimensions Parameter Standard MetricPower Requirements Average Power Mode DefinitionsEPA Energy Star Compliance Environmental LimitsReliability Specifications Shock and VibrationSafety Regulatory Compliance Radiated Electromagnetic Field Emissions EMC ComplianceCanadian Emissions Statement Handling and Installation Hard Drive Handling PrecautionsPre-formatted Drive Important NoticeUnpacking and Inspection Multi-pack Shipping ContainerPhysical Installation Recommended Mounting ConfigurationRepacking Handling Precautions Tools for InstallationSystem Requirements Drive Identification InformationGeneral Requirements Hard Drive IdentificationSystems Using Cable Select Installing 5.25-inch Mounting Brackets and RailsInstalling in a Device Bay Mounting Drive in SystemAttaching Interface and Power Cables Attaching System CablesSystem Setup Setting the Bios CmosBios Cmos Parameters Hard Drive Preparation System Hangs During Boot Interface Connector AT Interface DescriptionPin Description Summary PIN Name Signal Name Signal Description Pin Description TableTiming Parameters Mode PIO TimingDMA Timing Mode MIN MAX Ultra DMA TimingSustained Ultra DMA Data In Burst Device Terminating an Ultra DMA Data In Burst Initiating an Ultra DMA Data Out Burst Device Pausing an Ultra DMA Data Out Burst Device Terminating an Ultra DMA Data Out Burst Error Register Features RegisterHost Software Interface Task File RegistersSector Count Register Sector Number RegisterCylinder Number Registers Device/Head RegisterCommand Register Command Name Command Code Parameters Used SDH SummaryControl Diagnostic Registers Alternate Status RegisterDevice Control Register Digital Input RegisterReset and Interrupt Handling Reset HandlingInterrupt Handling Interface Commands Set Feature CommandsRead Commands Read SectorsRead Verify Sectors Read DMA Read MultipleWrite Commands Set Multiple ModeWrite Sectors Write Verify SectorsWrite Multiple Write DMASet Feature Commands Set Features ModePower Mode Commands Sleep Mode Initialization Commands Identify Drive15-8 = PIO data transfer mode = Write Cache enabled Initialize Drive Parameters Seek, Format and Diagnostic Commands Execute Drive DiagnosticFormat Track A.R.T. Command Set Execute S.M.A.R.TService and Support Service PolicyNo Quibble Service SupportMaxFax Service Customer ServiceInternet Access Time GlossaryCylinder Zero Gigabyte GB Logical Block Addressing Read Gate Signal THIN-FILM Media