Maxtor 91024D4, 90750D3, 91280D5, 91536D6, 91792D7 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 Revisions 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 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 Before You Begin General Requirements Mounting Drive in System Attaching Interface Power Cables System Setup Hard Drive Preparation System Hangs During Boot Interface Connector SignalAT Interface Description Pin Description SummaryPIN Name Signal Name Signal Description Pin Description TableTiming Parameters Mode PIO TimingDMA Timing Ultra DMA Timing Timing Parameters all times in nanosecondsSustained 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 Glossary Direct Access Direct Memory AccessError Correction Code ECC Error FreeHard Error Head Disk Assembly HDAFile Allocation Table FAT Flux Changes PER InchPhase Locked Loop PLL Logical AddressLogical Block Addressing Logical SectorRandom Access Memory RAM Read Gate SignalRecoverable Error Sector Pulse SignalUN-CORRECTABLE Error Unrecoverable ErrorWrite Gate Signal THIN-FILM Media