IBM System Storage TS2230, Setup, Operator, And Service Manual

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gigabyte (GB)
1 000 000 000 bytes.
Gigabit Interface Converter (GBIC)
Converts copper interface to optic interface.
gnd Ground.
H
hertz (Hz)
Unit of frequency. One hertz equals one cycle per second.
hex
Hexadecimal.
High Voltage Differential (HVD)
A logic signaling system that enables data communication between a
supported host and the library. HVD signaling uses a paired plus and
minus signal level to reduce the effects of noise on the SCSI bus. Any noise
injected into the signal is present in both a plus and minus state, and is
thereby canceled. Synonymous with
differential .
HVD SCSI Bus High Voltage Differential
Hz Hertz (cycles per second).
I
IBM Ultrium Tape Drive
Located within the library, a data-storage device that controls the
movement of the magnetic tape in an IBM LTO Ultrium Tape Cartridge.
The drive houses the mechanism (drive head) that reads and writes data to
the tape.
ID Identifier.
identifier (ID)
(1) In programming languages, a lexical unit that names a language object;
for example, the names of variables, arrays, records, labels, or procedures.
An identifier usually consists of a letter optionally followed by letters,
digits, or other characters. (2) One or more characters used to identify or
name data element and possibly to indicate certain properties of that data
element. (3) A sequence of bits or characters that identifies a program,
device, or system to another program, device, or system.
IML Initial microprogram load.
initial microprogram load (IML)
The action of loading a microprogram from an external storage to writable
control storage.
initiator
The component that executes a command. The initiator can be the host
system or the tape control unit.
INST Installation.
interface
A shared boundary. An interface might be a hardware component to link
two devices or it might be a portion of storage or registers accessed by two
or more computer programs.
interposer
The part used to convert a 68-pin connector to a 50-pin D-shell connector.
Glossary
G-7