076R155-000
SpectraComm 553 Fractional T1 DSU
B-1
Issue 7
Installation and Operation Manual
Appendix B:
Interface Signals
Table B-1
ITU-T V.35 DTE Interface Signals
DB25
V.34
Pin
Circuit
Designation
Description
ITU-T
EIA
7
B
102
AB
Establishes a common ground reference for all interface circuits
except protective ground, pin A.
4
C
105
CA
Indicates to Data Set that DTE is prepared to transmit.
5
D
106
CB
Indicates to DTE that Data Set is prepared to transmit.
6
E
107
CC
Indicates to DTE that Data Set is operational.
8
F
109
CF
Indicates to DTE that Data Set is receiving data (not idle or OOS
codes).
25
NN
142
TM
Indicates to DTE that Data Set is in a test mode.
2
3
P
S
103
103
BA(A)
BA(B)
Transfers data signals from DTE for transmission over communication
line.
3
14
R
T
104
104
BB(A)
BB(B)
Transfers data signals received over communication line by Data Set
to DTE.
24
11
U
W
113
113
DA(A)
DA(B)
Transfers transmitter signal timing information from DTE to Data Set.
17
9
V
X
115
115
DD(A)
DD(B)
Transfers receiver signal timing information from Data Set to DTE.
15
12
Y
AA/a
114 DB(A)
DB(B)
Transfers transmitter signal timing information from Data Set to DTE.
20
H
108/2
CO
Indicates to Data Set that DTE is prepared for data communication.
18
L
141
LL
Controls Local Loopback test
21
N
140
RL
Controls Remote Loop test