Maxtor 5120 Control Diagnostic Registers, Alternate Status Register, Device Control Register

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HOST SOFTWARE INTERFACE

Control Diagnostic Registers

These I/O port addresses reference three Control/Diagnostic registers:

I/O PORT	READ	WRITE

3F6h	Alternate Status	Fixed Disk Control

3F7h	Digital Input	Not used

Alternate Status Register

Contains the same information as the Status register in the Task File. However, this register may be read at any time without clearing a pending interrupt.

Device Control Register

Contains the software Reset and Enable bit to enable interrupt requests to the host. Bit definitions follow:

7	6	5	4	3	2	1	0

0	0	0	0	0	SRST	IEN	0

					Reset	IRQ Enable

Reset – Setting the software Reset bit holds the drive in the reset state. Clearing the bit re-enables the drive. The software Reset bit must be held active for a minimum of 5 µsec.

IRQ Enable – Setting the Interrupt Request Enable to 0 enables the IRQ 14 signal to the host. When this bit is set

to 1, IRQ14 is tri-stated, and interrupts to the host are disabled. Any pending interrupt occurs when the bit is set to 0. The default state of this bit after power up is 0 (interrupt enabled).

Digital Input Register

Contains information about the state of the drive. Bit definitions follow:

7	6	5	4	3	2	1	0

x	-WG	-HS3	-HS2	-HS1	-HS0	-DS1	DS0

Reserved		Head	Head	Head	Head	Drive	Drive
	Gate	Select 3	Select 2	Select 1	Select 0	Select 1	Select 0

Bit 7 of the host data bus is not driven when this register is read.

-Write Gate – Reflects the state of the active low write gate signal on the drive.

-Head Select 3 through -Head Select 0 – Represents the ones complement of the currently selected head number.

-Drive Select 1 – Is 0 if drive 1 selected; 1 otherwise.

-Drive Select 0 – Is 0 if drive 0 selected; 1 otherwise.

6 – 5

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Contents HA RD Drive Produc T MA Nual 92048U8, 91792U7, 91536U6, 91280U5, 91024U4 and 90750U3 DiamondMax PlusRevisions Manual No U T I O N Before You BeginContents Handling and Installation Product SpecificationsHost Software Interface AT Interface DescriptionGlossary Interface CommandsService and Support Figures Abbreviations IntroductionMaxtor Corporation Manual OrganizationNumbering Signal ConventionsConventions Key WordsProduct Description DiamondMax Plus 5120 Key FeaturesFunctional / Interface Product FeaturesSoftware ECC Correction On-the-Fly Hardware Error Correction Code ECCLogical Block Addressing Defect Management Zone DMZAutomatic Write Reallocation AWR Read-Ahead ModeCache Management Buffer SegmentationMajor HDA Components Dual Drive Support Subsystem ConfigurationJumper Location/Configuration Cylinder LimitationModels and Capacities Product SpecificationsDrive Configuration Performance SpecificationsParameter Standard Metric Physical DimensionsEnvironmental Limits Power Requirements AveragePower Mode Definitions EPA Energy Star ComplianceShock and Vibration Reliability SpecificationsCanadian Emissions Statement Safety Regulatory ComplianceRadiated Electromagnetic Field Emissions EMC Compliance Important Notice Handling and InstallationHard Drive Handling Precautions Pre-formatted DriveMulti-pack Shipping Container Unpacking and InspectionRepacking Physical InstallationRecommended Mounting Configuration Drive Identification Information Handling PrecautionsTools for Installation System RequirementsHard Drive Identification General RequirementsMounting Drive in System Systems Using Cable SelectInstalling 5.25-inch Mounting Brackets and Rails Installing in a Device BayAttaching System Cables Attaching Interface and Power CablesBios Cmos Parameters System SetupSetting the Bios Cmos Hard Drive Preparation System Hangs During Boot Pin Description Summary Interface ConnectorAT Interface Description Pin Description Table PIN Name Signal Name Signal DescriptionPIO Timing Timing Parameters ModeDMA Timing Ultra DMA Timing Mode MIN MAXSustained 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 Task File Registers Error RegisterFeatures Register Host Software Interface Device/Head Register Sector Count Register Sector Number Register Cylinder Number RegistersCommand Register Summary Command Name Command Code Parameters Used SDHDigital Input Register Control Diagnostic RegistersAlternate Status Register Device Control RegisterInterrupt Handling Reset and Interrupt HandlingReset Handling Set Feature Commands Interface CommandsRead Verify Sectors Read CommandsRead Sectors Read Multiple Read DMAWrite Verify Sectors Write CommandsSet Multiple Mode Write SectorsWrite DMA Write MultipleSet Features Mode Set Feature CommandsPower Mode Commands Sleep Mode Identify Drive Initialization Commands15-8 = PIO data transfer mode = Write Cache enabled Initialize Drive Parameters Format Track Seek, Format and Diagnostic CommandsExecute Drive Diagnostic Execute S.M.A.R.T A.R.T. Command SetSupport Service and SupportService Policy No Quibble ServiceInternet MaxFax ServiceCustomer Service Glossary Access TimeCylinder Zero Gigabyte GB Logical Block Addressing Read Gate Signal THIN-FILM Media