1-Port and 2-Port ISDN-PRI Network Module Configuration Note 11
PRI Module Pinouts
Figure 13
Connecting a CE1/PRI-U Module to an E1 CSU (DB-15-to-BNC Connectors)
PRI Module Pinouts
This section describes PRI network module cables and lists their pinouts.
CT1/PRI Pinouts
Two standard T1 serial cables are available for the CT1/PRI network module, straight-through and
null-modem. A straight-through cable connects the router to an external channel service unit (CSU).
Null-modem cables are used for back-to-back operation and testing.
T1 interface cables have two male DB-15 connectors (one at each end) to connect the CT1/PRI
module with the external T1 CSU. Figure 14 shows the cable and connectors. Table 1 lists the pinout
for the straight-through T1 cable, and Table 2 lists the pinout for the null-modem T1 cable.
Figure 14
T1 Interface Cable
LOOPBACK
CTRLR 0
EN
cE1-U
PRI
H7471
LOCAL
ALARM
REMOTE
ALARM
CARRIER
DETECT
CE1/PRI-U
BNC connectors
E1 CSU
E1 cable for 75-ohm
unbalanced connections
with BNC connectors
at the network end
Pin 1
Pin 9
Pin 11
Pin 3
Pin 1
Pin 9
Pin 11
Pin 3
72-XXXX-01
MIP
T1 or null-modem
connector (typical)
H2385
