CentreCOM 3600 Series Hub/Repeaters
19
The RS232 Management Port
AT-3600 Series Repeaters have a special management port for connecting a
user-supplied serial device. This port conforms to the signaling
characteristics of EIA standard RS232 and implements the signals necessary
to support an asynchronous device. The physical connector is not, however, an
RS232 DB25, but is instead a DB9 (see Figure 5) commonly used on PCs.
A 25-pin to 9-pin adapter comes with all manageable AT-3600 Series Repeater
models. This adapter enables a change from connectors with a pin interface to
connectors with a hole interface.
For some applications you will need a conversion cable. One kind of
conversion cable allows the AT-3600 Series Repeater to perform as Data
Communication Equipment (DCE); a different cable allows the repeater to
serve as Data Terminal Equipment (DTE). You may connect the terminal
directly (with the repeater as a DCE), or through an asynchronous modem
(using a “null modem cable”) to convert the AT-3600 interface to a DTE.
Table 2 shows pin assignments for both cabling methods.
Table 2:
RS232 Cable
Figure 5:
AT-3600 RS232 DCE
Connections
Note
5
4
3
2
1
9
8
7
6
AT-3600 DB9
Signal Name
Terminal DTE DB25
Modem DCE DB25
1
N/C
—
—
2
RD
3
2
3
TD
2
3
4
DTR
20
6
5
SG
7
7
6
DSR
6
20
7
RTS
4
5
8
CTS
5
4
9
N/C
—
—
