Digital Link DL600E, Руководство пользователя

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G-8 DL600E E1 Data Multiplexer UserÕs Guide
repeater
Ñ Equipment that receives a pulse train, ampliÞes it, retimes it, and
then reconstructs the signal for retransmission.
return to zero
ÑMethod of transmitting binary information such that, after
each encode bit, voltage returns to the zero level.
RI (Ring Indicator)
Ñ A data port signal.
RJ48S
Ñ An
8
-position keyed jack used to connect services that are covered
under
FCC
Part
68
Rules, such as public switched digital service
(PSDS)
,
switched 56,
19.2
Kbps service,
64 K
bps service, and synchronous digital data
with secondary channel.
RLSD
Ñ Receive Line Signal Detect, a data port signal
RS232
Ñ
A TIA/EIA
standard for serial transmission between computers and
peripheral devices (modem, mouse, an so on.). It uses a 25-pin
DB25
or 9-pin
DC9
connector. Its normal cable limitation of 50 feet can be extended to sev-
eral hundred feet with high-quality cable. RS232 deÞnes the purpose and sig-
nal timing for each of the 25 lines; however, many applications use less than a
dozen. RS232 transmits positive voltage for a 0 bit, negative voltage for a 1.
RS232-C
ÑAn
EIA
speciÞed physical interface, with associated electrical sig-
naling, between data circuit terminating equipment
(DCE)
and data terminat-
ing equipment
(DTE).
RS449
ÑA common
37-
position interface for data terminal equipment and
data circuit terminating equipment employing serial binary data interchange. A
balanced interface, based on unipolar digital signals, depending more on cur-
rent ßow than voltage, therefore supports greater distances
RS232
.
RTS(Request to Send)
ÑA signal sent by
DTE
to
DSU/CSU
indicating
DTE
has
data ready to transmit.
S
SCR (Serial Clock Receive)
Ñ A unipolar clock from the
DCE
signal. A data
port signal.
SCT (Serial Clock Transmit)
Ñ A unipolar clock from the
DCE
signal. A data
port signal.
SCTE (Serial Clock Transmit External)
Ñ The clock signal is echoed from
the
DTE for the purpose of
timing incoming data on long cable runs.