Quantum LTO-9 HH SAS, User Manual

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Glossary
104 Quantum LTO-9 HH SAS User’s Guide
High Voltage Differential (HVD) A logic signaling system that enables
data communication between a supported host and the device.
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.
Hz Hertz (cycles per second).
I
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) 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.
intervention required Manual action is needed.
INTRO Introduction.
I/O Input/output.
IOP Input/output processor.
IPL Initial program load.
ITST Idle-time self-test.