Filter
Top Products
NTI NODEMUX SERIES UNIVERSAL KVM SWITCH
27
RS232 CONTROL
RS232 Connections and Configuration
Remote Connection
The RS232 Interface is designed to meet the RS232C standard and can be controlled from any terminal (CPU or other controller
with an RS232 communications port.). The pin-out for the DB-9 connector on the unit is as follows:
RS232 Connector (DB-9 FEMALE)
PIN SIGNAL FUNCTION
1 CD Carrier Detect
2 TXD Transmit data (RXD at host)
3 RXD Receive data (TXD at host)
4 DTR Data terminal ready
5 GND Signal ground
6 DSR Data set ready
7 RTS Request to send
8 CTS Clear to send
9 - No connection
Note: Security must be disabled or user access granted on the port(s) to be selected by RS-232 control.
On the DB-9 female connector, pins 1 (DCD), 4 (DTR), and 6 (DSR) are shorted and pins 7 (RTS) and 8 (CTS) are shorted.
Therefore, host handshaking is bypassed and TXD and RXD are the only active signals. A straight through DB-9 cable (not null
modem) will work for most CPUs. To daisy chain multiple units, a Matrix Y-1 cable is used (see page 29) for each NODEMUX in
the chain. The last unit will have no connection on its output port and should have DIP switch 1 ON (see table under "Unit
Address and Loop Back" on page 28).
Configuration via Dip Switches
Note: Only legacy NODEMUXs have the dip switch for RS232 configuration. If the dipswitch (as shown above) is not
present, refer to "Configuration via OSD" on page 28.
Baud Rate
The baud rate can be changed by powering down the unit, changing the 8 position RS232 dip switch on the rear of the
NODEMUX (legacy switches only) , and then powering back up. The table below shows how to set the baud rate.
DIP SWITCH BAUD RATE
4 3 2
OFF OFF OFF 300
OFF OFF ON 600
OFF ON OFF 1200
OFF ON ON 2400
ON OFF ON
ON ON OFF
ON ON ON
9600
Figure 30- RS232 dip switches
Rear View of ST-4U-RS
CPU 1CPU 2CPU 3
CPU 4
NTI
5VDC
2A
-
+
DEVICES
R
7
V
I
D
E
O
4
V
I
D
E
O
3
V
I
D
E
O
2
V
I
D
E
O
1
M
O
N
I
T
O
R
DAISY DAISY
OUT IN
NETWORK TECHNOLOGIES INCORPORATED 1275 Danner Drive, Aurora Ohio 44202 330-562-7070 www.nti1.com
RS232
ON
OFF
1 2 3 4 5 6 7 8
ON
OFF
1 2 3 4 5 6 7 8