Seagate STT8000A manual Theory of operations, Block diagram

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Theory of operationsChapter 7

Theory of operations	7
Theory of operations

Overview

The STT8000 ATAPI minicartridge drive is based on proven Seagate designs, Seagate firmware, and the latest technology. This drive uses second generation, custom LSIs for efficient circuit layout and increased reliability with low power consumption. The drive also uses flash EEPROM devices for easy firmware upgrades.

This chapter describes the drive in more detail and explains implementation specific information.

Block diagram

The electronics of the STT8000 ATAPI minicartridge drive are laid out on one main printed circuit board (PCB). Figure 7-1 shows a simplified block diagram of the drive components.

Figure 7-1

Simplified block diagram of drive components

256KB	V20 uP
EEPROM	10.0 MHz
5 Volt			Head
		Read/Write	Head
	40MHz	Read/Write	STTI or
		PHILIPS	STTI or
		PHILIPS	Read/Rite
	Crystal		Read/Rite
	Crystal		No RWW
			No RWW
RAWHIDE (DelMar + IDE)		Stepper
RAWHIDE (DelMar + IDE)		Motor
		Motor
IDE	Digital ASIC
Interface	Buffer Mgr.	Motor Control	Capstan
	ECC	Nat. Semi.	Capstan
	ECC	Nat. Semi.	Motor
	RWW	NDM 3000	Motor
	RWW	NDM 3000
IDE ONLY
	512KB	Sensors	Cartridge Present
	512KB		Cartridge Present
	DRAM		Write Protect
Shading denotes			Tape Hole
differences from			Top Stop
TR-4 (Bali2)

STT8000A Product Manual

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Contents STT8000A Atapi Minicartridge Drive Product Manual Page FCC Notice Important Information About This Manual Table of Contents Atapi interface Tape format Glossary Acronyms and measurements Drive overview IntroductionSTT8000A internal drive without mounting brackets Features Minicartridge technology overview Typical system configurationsReferences Flash EepromSoftware Chapter Title Description About this manualOverview SpecificationsPhysical specifications STT8000A 3.5-Inch mount general dimensions Specification Measurement Power specificationsFeature Specification Performance specificationsEnvironmental requirements Specification Operational Non-operationalMean-Time-To-Repair ReliabilityMean-Time-Between Failures Tape capacities and formats Recommended tapesTUV & IEC-RHEINLAND Regulatory complianceIntroduction InstallationBefore you begin Handling guidelinesJumper block and jumper settings Setting jumpersAligning the drive in the computer Installing the driveMounting dimensions Mounting holes on internal drive without mounting brackets Pin Assignment Description Source ATA-2 Interface pin assignmentsREQ Chapter Installation Front panel LED Drive operation and maintenanceLoading and unloading cartridges Using Travan cartridgesTravan cartridge write-protect switch-locked position Setting the write-protect switchLoading revised firmware via Seagate firmware cartridge Caring for the drive Care and maintenance of the drive and cartridgesCaring for tape cartridges Capstan Tape Head Troubleshooting Chapter ATA-2 Interface ATA-2 SignalsAtapi interface Abrt ATA registersBits Mnemonic Description Previous Cmd Int Reason Supported ATA CommandsFeature Number Set Feature Commands Atapi Identify Device A1h Atapi Packet Command A0h DSC Atapi interfaceErase command Bit Byte Inquiry commandLoad/Unload command Locate command Log Select command Log Sense command Following table presents the Error Counter Page layout Error Counter Page ReadFollowing table presents the Tape Capacity Page layout Tape Capacity Page CodeMode Select command Code Description Mode Sense commandMode Block Descriptor Mode Parameter HeaderMode Capabilities and Mechanical Status Mode Medium PartitionMode Tape Parameters Read command Following table describes the Read Position layout Read Position commandChapter Atapi Interface Request Sense command Following table describes the Request Sense layout Rewind command Space command Test Unit Ready command Write command Write Filemark command Write Buffer download microcode command Track positions Tape formatTape partitioning Frames Track numberingTrack format General track layout Blocks Tape reference servo patternRandomization Write equalizationChapter Tape format Theory of operations Block diagramMechanics Capstan drive motor assemblyCartridge load mechanism ChassisHead design Sensors and switchesControl circuits Travan minicartridge Media-Travan minicartridgesGlossary Appendix a Glossary Glossary Appendix a Glossary Acronyms and abbreviations Acronyms and measurementsLSI Measure Meaning Units of measurementAppendix B Acronyms and Measurements