IBM Magstar MP 3570 C Series, Maintenance Information

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Operating Systems
Refer to IBM Magstar MP 3570 Tape Subsystem Introduction and Planning Guide, C-Series Models,
GA32-0392 for planning for program support.
SCSI Physical Interface Characteristics
The 3570 Tape Subsystem operates as a SCSI-2 device with SCSI-3 features. The instruction set is
SCSI-2, but includes SCSI-3 commands and mode sense data.
The 3570 Tape Subsystem attaches to host processors through the Magstar MP SCSI system adapter,
which is a fast/wide (16-bit) differential SCSI interface. It uses a shielded high-density SCSI-3 68-pin P
connector that accommodates 16 bus addresses. The 3570 attaches to a differentially driven, wide (16
bit) SCSI-3 P-cable.
Under the SCSI-2 protocol, this type of attachment allows cable lengths of up to 25 m (81 ft) with the
appropriate cable and terminator selection. The stub length at each device must not exceed 0.2 m (0.66
ft).
The 3570 Tape Subsystem also logically supports the narrow (8-bit) protocol. An interposer is required to
connect the 3570 Tape Subsystem to a SCSI-2 bus.
Note: Only 8 bus addresses (0 to 7) are valid for an 8-bit SCSI bus.
Bus Termination
The SCSI bus and all of the wires in the SCSI cable must be properly terminated according to the SCSI
standard. This termination is especially important if a system mixes devices or initiators with 68-pin
connectors with those of the older 50-pin style.
An external terminator may be mounted into a socket that is a part of the SCSI cable connector. A
terminator must be installed on the last device on each end of a string of multiple devices. In a
single-device installation, the terminator is installed in the socket of this device. The 3570 Tape
Subsystem is delivered with an external differential terminator included, but it is not installed.
SCSI Bus Jumper
| Models C02, C12 and C22 include a SCSI Bus Jumper, a short SCSI cable which is attached or removed
| depending on the library configuration.
|
Base Configuration:
For Models C02, C12 and C22 set up in Base Configuration, the SCSI Bus
| jumper is attached between the two drives so the drives are on the same SCSI bus.
|
Split Configuration:
For Models C02, C12 and C22 set up in a Split configuration, the SCSI Bus
| Jumper is removed so each drive port is attached to a separate SCSI bus. Thus, each drive port in a Split
| Configuration has the same cable and termination requirements as a single-drive model C01, C11 and
| C21.
Device Characteristics
Figure 20 shows the physical specifications of the 3570 Tape Subsystem.
INTRO
Introduction
INTRO-9