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NTI KEEMUX Series PS/2 KVM Switch
18
RS232 CONTROL
(Optional)
RS232 Connections and Configuration
Remote Connection
The RS232 Interface (optional) is designed to meet the RS232C standard and can be controlled from any CPU or other controller
with an RS232 communications port. The pin-out for the DB-9 connector(s) 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 serial cable
(not
null modem- see specifications on page 26
) will work for most CPUs. To daisy chain multiple units, a Matrix Y-1 cable is used
(see page 19) for each KEEMUX in the chain. The last unit in the chain should have DIP switch 1 ON (see table under "Unit
Address and Loop Back" on page 19).
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 KEEMUX,
and then powering back up. This table 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
ON
OFF
1 2 3 4 5 6 7 8
Rear View of KEEMUX-P4-RS
5VDC
2A
-
+
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
Mouse
CPU 1
C
P
U
1
C
P
U
2
C
P
U
3
C
P
U
4
CPU 2
CPU 3
CPU 4
Keyboard
Daisy Daisy
Out In
NTI
Tel:330-562-7070
Fax:330-562-1999
1275 Danner Dr
Aurora, OH 44202
www.nti1.com
R
PS/2 DEVICES
RS232
ON
OFF
1 2 3 4 5 6 7 8