IBM Magstar MP 3570 C Series, Информация по обслуживанию

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recorded when the tape moves in a forward direction until the physical end of the tape is reached. Then,
using an electronic head switch (not physically moving the head itself in any direction but switching to a
second set of read-write heads), a second set of 18 tracks is recorded when the tape moves in a
backward direction until the physical beginning of the tape is reached.
In the 3590 a second generation of thin film magneto resistive (MR) heads is used, which, together with
the 3590 tape medium allows recording with much higher area density, both in number of bits as well as
number of tracks per inch. Similar to the 3590, the 3570 data is written in blocks of user data using
multiple track format and where ECC information are recorded differently compared to the older track
formats. The first set of eight tracks is written from the halfway point along the length of the tape to near
the end of the tape, where the head is indexed to the next set of eight tracks for return to the tape center.
The process continues until all 128 tracks are written. The process is repeated in the other direction of
tape until the tape is full.
Note: Not all tape cartridges will be full from one end to the other. This example is used to show how a
complete tape cartridge could be utilized for maximum effectiveness.
An example of tape track recording progression is shown in Figure 17. The 3570 recording process is
very similar to that of the 3590, but with fewer head tracks and with a two-reel cartridge.
Figure 17. Serpentine Interleaved Track Sets
IBM 3570 Tape Subsystem, C-Series Models
The following single drive 3570 models are available:
Model C00 Drive is a customer setup (CSU) Tape Subsystem which may be installed on a desk or
table. It does not include the library attachment. See Figure 18 on page INTRO-8.
Model C01 is a customer setup (CSU) stand-alone library Tape Subsystem with a 20-cartridge random
access cartridge loader. See Figure 19 on page INTRO-8.
Model C11 is a rack-mounted library tape subsystem with a 20-cartridge random access cartridge
loader. The Model C11 is similar to the Model C01 except for external covers and being
rack-mounted. See Figure 19 on page INTRO-8.
| Model C21 is a customer setup (CSU) rack-mounted library Tape Subsystem with a 20-cartridge
| random access cartridge loader. It is identical to a Model C11 except that it attaches only to IBM
| Netfinity or IBM PC Server systems, and is mounted in a EIA-310-D industry standard 19-inch rack
| such as the IBM Netfinity Rack (9306900) or NetBAY22 (9306200). See Figure 19 on page INTRO-8.
INTRO
Introduction
INTRO-5