5190/5194 Modular Tape Subsystem Manual

Configuring the Modular Tape Subsystem
5190/5194 Modular Tape Subsystem Manual—426878-002
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Configuring the Modular Tape Subsystem Online
Using COUP
The 3216 controller can control one or two tape drives. If the controller manages
only one drive, use the default unit number (5). If the controller manages two
drives, use unit numbers 4 and 5.
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Using COUP, you can specify compression as a device attribute for the 5190 tape
drive. (The 5194 tape drive ignores this attribute, because it always operates in
compression mode.)
You can use these attributes in COUP to enable or disable compression:
The default attribute for the 5190 tape drive is NOCOMPRESSION. The COUP
attribute establishes the default mode for the 5190 you are configuring. After you
have configured the 5190 tape drive, you can override this setting, if you need to,
in a number of ways. To see a description of each of the methods for enabling or
disabling compression, see Controlling Data Compression (5190 Tape Drive) on
page 4-44.
Example 4: Starting a Tape Drive
After adding a controller and device (as shown in the examples on page 2-8, page 2-9,
and page 2-10), you must start it before the operating system can recognize it.
In this example, the COUP START command starts an I/O process for the tape drive
$TAPE1. Returned messages indicate that the tape drive has been started.
Attribute 5190 Tape Drive Action
NOCOMPRESSION Data is written without compression
COMPRESSION Data is written using IDRC compression
11) START $TAPE1
IOP for device $TAPE1 successfully started in CPU 0.
IOP for device $TAPE1 successfully started in CPU 1.
Device $TAPE1 has been successfully started.