Seagate CD72LWH - Page 6

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DAT 72/DDS Product Manual
Unloading a Cartridge................................................................................................27
Initializing a Blank Cartridge ......................................................................................28
DDS Cartridge Compatibility......................................................................................28
Write-Protecting a Cartridge ......................................................................................28
LED Codes.................................................................................................................29
Clean LED...........................................................................................................30
Media LED...........................................................................................................30
Drive LED............................................................................................................30
LED Code Summary ...........................................................................................31
Cleaning the Tape Heads ..........................................................................................31
When to Clean the Tape Heads..........................................................................31
How to Clean the Tape Heads ............................................................................32
Automatic Drive Spin-Down and Write.......................................................................32
Operating the Drive in High-Temperature or Humidity Conditions ............................32
Data Compression.....................................................................................................33
Loading Revised Firmware from Seagate Firmware Cartridges................................33
Flash Memory......................................................................................................33
Firmware Download Process via Tape ...............................................................33
Theory of Operations 35
Overview....................................................................................................................35
Drive Mechanism.................................................................................................35
Motors and Control Circuits .......................................................................................38
Timing Tracking Circuitry.....................................................................................38
Signal-Processing Electronics.............................................................................38
Flash Memory ............................................................................................................38
Sensors......................................................................................................................39
Read-After-Write........................................................................................................39
Media Recognition System (MRS).............................................................................40
About the DDS Data Cartridge...................................................................................40
Data Compression 43
Introduction ................................................................................................................43
Overview .............................................................................................................43
Data Compression Considerations......................................................................44
Hardware Compression.......................................................................................45
Data Integrity.......................................................................................................45
DCLZ Algorithm .........................................................................................................46
Simplified Compression Operation......................................................................46
Dictionary ............................................................................................................47