Verilink PRISM 3111 (34-00242) Product Manual - Manual (Page 20)

12 C HAPTER 2: I NSTALLATION
11). It can be set to 1.2, 2.4, 9.6 or 19.2 kbps. This port is a DCE port configured
for 8 bits, no parity, and 1 stop bit. The physical connections are 8-pin modular
jacks (electrically RS-232). Figure 2-2 provides the pinout assignments. See
Ordering Information on page 92 for cable information.
The terminal interface may be accessed through this port as well as the Call On
Alarm feature. You may access this port through either a direct connection or a
dial-up connection via an AT command set compatible modem. The modem
should be optioned to ignore DTR, enable auto answer, inhibit command echo, and
return verbose result codes.
If you call the unit and send the BREAK command before receiving the CONNECT
message, the modem will hang-up.
T1 DTE The optional T1 DTE port is a DSX interface. The bit rates are configured
through the front panel interface on LCD units (page 33), through the rear panel
DIP switch S4 on non-LCD units (page 19) or through the terminal interface (page
61). The physical connection is an 8-pin modular jack. Table 2-3 provides the
pinout assignments. T1 DTE port line coding is not dependent on the line coding
of the network interface. ESF to D4 framing conversion is supported.
An RJ-48X modular jack and loopback (100
Ω
+5%) is available for the T1 DTE
port. Unlike an RJ-48C, the RJ-48X contains a shorting bar that engages when a
cable is not plugged into the connector forcing the transmitted data to be looped
back into the unit. When ordering a PRISM 311/3112 with an RJ-48X connector,
specify option 2 (T1 DTE with loopback) for the T1 DTE selection.
NET The Network interface connection contains an automatic line build-out (ALBO)
allowing the unit to be located a substantial distance away from the telco network
interface with a receive signal level to -27 dB.
The network interface LBO level should be set as instructed in the Line Parameters
section on page 58. Maximum suggested cable lengths for the connection from the
unit to the network are listed in Table 2-4. Calculations are based on a cable
temperature of 70
°
F, 0.083
µ
F /mile capacitance, a 27 dB loss and a 100
Ω
,
non-loaded, twisted pair cable.
✍
Table 2-3 T1 DTE Pinout
Pin T1 DTE Interface
1 Data Out
2 Data Out
3,6 Not Used
4 Data In
5 Data In
7, 8 Chassis Ground