Instruction manual

MERLIN LEGEND Communications System Release 5.0
Installation
555-650-140
Issue 1
June 1997
Glossary
Page GL-19
Flash ROM Beginning with Release 3.0, a type of read-only
memory provided on the
processor module , used to
supply system features.
foil shield Copper foil sheet (for power units) used to prevent
excessive noise on the module.
forced idle Condition of the system during certain programming
or maintenance procedures; system prevents initia-
tion of new calls.
foreign exchange See FX
.
frame One of several segments of an analog or digital sig-
nal that has a repetitive characteristic. For example,
a
DS1 frame consists of a framing bit and 24 bytes,
which equals 193 bits.
framing format Pattern of
frames used in transmissions.
frequency
generator
See
ring generator .
FRL (Facility Restriction Level)
ARS calling restriction
type that restricts outgoing calls to certain specified
routes.
FX (foreign exchange) Central office (
CO ) other than the
one that is providing local access to the public tele-
phone network.