User guide

B-2 Solo E1 DSU User Guide—June 1998
B
Table B-3 describes DATA port signal from the equipment to the DSU.
Clear To Send CTS
(D)
CTS-A, B
(5,13)
CS-A, B
(9,27)
Described in Table B-4
Ring Indicator RI (J) Always inactive
Test Mode TM (25) TM (18) Described in Table B-4
Table B-3 DATA Port Signals—Equipment to Solo E1 DSU
Name V.35 EIA-530 X.21 RS-449 Description
Send Data SD A, B
(P, S)
TD-A, B
(2, 14)
Transmit
(2, 9)
SD A, B
(4,22)
Data stream from DTE.
Data Terminal
Ready
DTR
(H)
DTE
READY
(20,23)
RT A, B
(12,30)
Can be used to indicate loss of
DTE signal. The
DATA port can
be programmed to recognize Loss
of DTE as either loss of RTS
signal, loss of DTR signal or
neither (the condition is never
recognized). The hardware also
supports the detection of all zero
condition from the DTE which
could be used to indicate a loss
of DTE but currently not
supported.
Request To Send RTS
(C)
RTS
(4, 19)
Request To
Send
(3,10)
RS A, B
(7,25)
Affects assertion of CTS and
sending of Blue Alarm only if loss
is set to RTS.
Local Test/Local
Loop
LT
(K)
LL
(18)
LL
(10)
When line is asserted by DTE,
unit enters fractional DTE
Loopback test and remains in test
for as long as signal is held
active.
Send Clk
Transmit Echo
SCTE A, B
(U,W)
TT-A, B
(24,11)
TT A, B
(17,35)
SCTE can be either a timing
source to clock in the SD signal
or an external timing source for
use as a network transmit timing
reference
Ground
Table B-2 DATA Port Signals—Solo E1 DSU to Equipment
Name V.35 EIA-530 X.21 RS-449 Description