Quantum DLTtape SDLT 220, User Manual

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SDLT 220 and SDLT 320 Product Manual CHAPTER 2: SDLT 220/320 Product Information
81-85002-01 March 2004 2-7
the FPM are the only two modules that are field
replaceable. Customer adjustments to the TCM, DCM, or
EIM are not allowed, and will void the drive’s warranty.
2.4.1 Data Control Module
The Data Control Module (DCM) contains several of the functions and features of
Quantum’s LGMR technology, which is at the heart of the SDLT technology. Of
the five technologies that constitute the LGMR technology, two are found in the
DCM. These are the POS and the MRC heads.
The main functions of the DCM are to provide the path and guides for all the tape
motion inside the drive and to write data to and read data from the tape. In addition
to the POS and MRC heads described in
Section 2.3.2, “Pivoting Optical Servo”
on page 2-4 and Section 2.3.3, “Magneto Resistive Cluster Heads” on page 2-4 ,
the DCM contains a number of components that interact to perform these
functions. These components include the advanced head guide assembly, take-up
reel, drive motor, the optical servo system, and the tape heads.
The SDLT system tape path, from the first tape guide through the take up reel and
motor, has been simplified and improved from the previous DLT systems. The
addition of servo technology in the POS system has allowed Quantum engineers to
reduce the number of tape guides from six to four. This provides a simpler tape
path in the SDLT tape drive, improving performance and reliability.
In addition to its mechanical components, the DCM also contains printed circuit
boards that control the functions of the DCM and the tape heads.