Digital Equipment RW504-ZA, Service Manual

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1
Introduction
1.1 Optical Disk Libraries Overview
The RW504-ZA and RW524-ZA are optical disk libraries that contain a
multifunction optical drive. They have storage slots for sixteen 5.25-inch
optical disks for a total storage capacity of 10 Gbytes or 20 Gbytes, respectively.
Both rewritable and write-once optical disks can be used; they must be 512 bytes
per sector format.
There are two basic optical disk libraries:
• RW504-ZA (known as the RW504)
• RW524-ZA (known as the RW524)
The main difference between these two library versions is storage capacity. The
RW524 has approximately twice the storage capacity of the RW504. This added
capacity is due to a difference in the optical drives contained in the libraries. The
RW524 contains a 1.3-Gbyte drive, an enhanced version of the 650-Mbyte drive
that is used in the RW504 version libraries. The 1.3-Gbyte drive supports the use
of 1.2-Gbyte disks as well as the 594-Mbyte disks that are supported for use with
650-Mbyte drives. Other than the added support of 1.2-Gbyte disks, the RW524
libraries are mechanically, electrically, and operationally the same as the RW504
libraries, and both versions support the SCSI-2 command set.
1.2 Product Features
The optical disk library has the following features and meets the following
specifications:
• Direct online access to data
• High reliability and data security when using rewritable and write-once
5.25-inch optical disks
Introduction 1–1